Nephrology

Question 1

cRenal blood flow normally drains ___ of the cardiac output

Answer 1

~20%

Question 2

The most common clinical course of contrast nephropathy is characterized by a rise in SCr beginning ____ following exposure, peaking within ____ , and resolving within

Answer 2

24–48 h
3–5 days
1 week

Question 3

Definition of AKI

Answer 3

AKI is currently defined by a rise from baseline of at least 0.3 mg/dL within 48 h or at least 50% higher than baseline within 1 week, or a reduction in urine output to < 0.5 mL/kg per h for longer than 6 h.

Question 4

Diseases that may present with eosinophilluria (5)

Answer 4

Allergic interstitial nephritis
Atheroembolic dse
Pyelonephritis
Cystitis
Glomerulonephritis

Question 5

Diseases that may present with RBC casts (4)

Answer 5

Glomerulonephritis
Vasculitis
malignant Hypertension
Thrombotic Microangiopathy

Question 6

Diseases that may present with WBC casts (5)

Answer 6

Interstitial Nephritis
Glomerulonephritis
Plyelonephritis
Allograft Rejection
Malignant Infiltration of the kidney

Question 7

Diseases that may present with RTE casts (5)

Answer 7

ATN
Tubulointerstitial nephritis
Acute cellular allograft reaction
Myoglobulinuria
Hemoglobinuria

Question 8

Diseases that may present with granular casts (4)

Answer 8

ATN
GN
Vasculitis
TIN

Question 9

Diseases that may present with crystalluria

Answer 9

Acute uric acid nephropathy
Caox
Drugs or toxin (acyclovir, indinavir, sulfadiazin, amoxicillin)

Question 10

Fe Na of pre renal AKI

Answer 10

< 1%

Question 11

Dose for furosemide challenge

Answer 11

1-1.5 mg/kg

Question 12

UO of ________ after IV furosemide may identify patients at higher risk of progression to more severe AKI, and the need for renal replacement therapy

Answer 12

< 200 mL over 2 h a

Question 13

Molecule can be detected shortly after ischemic or nephrotoxic injury in the urine and, therefore, may be an easily tested biomarker in the clinical setting

Answer 13

KIM-1

Question 14

_____ is highly upregulated after inflammation and kidney injury and can be detected in the plasma and urine within 2 h of cardiopulmonary bypass– associated

Answer 14

NGAL

Question 15

patients with AKI should achieve a total energy intake of ____ kcal/kg per day.

Answer 15

20–30 kcal/kg per day

Question 16

Protein intake in AKI
_____ g/kg in noncatabolic AKI without the need for dialysis;
_____ g/kg per day in patients on dialysis;
and up to a maximum of ____ per day if hypercatabolic and receiving continuous renal replacement therapy

Answer 16

0.8–1.0 g/kg per day
1.0–1.5 g/kg
1.7 g/kg

Question 17

Alkali supplementation may attenuate the catabolic state and possibly slow CKD progression and is recommended when the serum bicarbonate concentration falls below ____ mmol/L.

Answer 17

20–23

Question 18

These PTH FGFR3 changes start to occur when the GFR falls below ___ mL/min.

Answer 18

60 mL/min

Question 19

_____ is a devastating condition seen almost exclusively in patients with advanced CKD. It is heralded by livedo reticularis and advances to patches of ischemic necrosis, especially on the legs, thighs, abdomen, and breasts

Answer 19

Calciphylaxis

Question 20

Blood thinner that is considered a risk factor for calciphylaxis

Answer 20

Warfarin

Warfarin is commonly used in HD patients in whom most direct oral anticoagulants (DOACs) are contraindicated, and one of the effects of warfarin therapy is to decrease the vitamin K–dependent regeneration of matrix GLA protein which is important in preventing vascular calcification

Question 21

Target PTH level for CKD

Answer 21

150 and 300 pg/mL

2-9x the ULN

Question 22

_______ is leading cause of morbidity and mortality in px at every stage of CKD

Answer 22

Cardiovascular disease

Question 23

First line therapy for CKD to reduce BP

Answer 23

Salt restriction

Question 24

In CKD patients with diabetes or proteinuria >1 g per 24 h, blood pressure should be reduced to ______ , if achievable without prohibitive adverse effects.

Answer 24

< 130/80 mmHg

Question 25

normocytic, normochromic anemia is observed as early as stage ___ CKD and is almost universal by stage __

Answer 25

3,4

The primary cause is insufficient production of erythropoietin (EPO) by the diseased kidneys.

Adequate bone marrow iron stores should be available before treatment with ESA is initiated. Iron supplementation is usually essential to ensure an optimal response to ESA

Question 26

Target Hb for CKD

Answer 26

10-11.5 g/dl

Question 27

Peripheral neuropathy usually becomes clinically evident after the patient reaches stage __ CKD, although electrophysiologic and histologic evidence occurs earlier.

Answer 27

4

P-eripheral neuropathy, P-or

Initially, sensory nerves are involved more than motor, lower extremities more than upper, and distal parts of the extremities more than proximal. The “restless leg syndrome” is characterized by ill-defined sensations of sometimes debilitating discomfort in the legs and feet relieved by frequent leg movement

Question 28

Class of OHAS that do not require dose reduction when EGFR is less than 50% of normal

Answer 28

SGLT 2 inhibitors

Question 29

A skin condition unique to CKD patients called _____ consists of progressive subcutaneous induration, especially on the arms and legs.

Answer 29

nephrogenic fibrosing dermopathy

The condition is seen very rarely in patients with CKD who have been exposed to the magnetic resonance contrast agent gadolinium.

Current recommendations are that patients with CKD stage 3 (GFR 30–59 mL/min) should minimize exposure to gadolinium, and those with CKD stages 4–5 (GFR < 30 mL/min) should avoid the use of gadolinium agents unless it is medically necessary

Question 30

Diseases where kidney size may be normal in the face of CKD (3)

Answer 30

diabetic nephropathy, amyloidosis, and HIV nephropathy

Question 31

Discrepancy ___ cm in kidney length suggests either unilateral developmental abnormality or dse process or renovascular dse with arterial insufficiency affecting 1 kidney more than the other

Answer 31

> 1 cm

Question 32

The most important complication of arteriovenous grafts is _______

Answer 32

thrombosis of the graft and graft failure

due principally to intimal hyperplasia at the anastomosis between the graft and recipient vein

Question 33

_______ is the most common acute complication of hemodialysis, particularly among patients with diabetes mellitus.

Answer 33

Hypotension

Question 34

_____ is the procedure of choice to rule out urinary obstruction or to confirm the presence of perirenal collections of urine, blood, or lymph.

Answer 34

Diagnostic ultrasound

Question 35

The first rejection episode is usually treated with IV administration of

Answer 35

methylprednisolone, 500–1000 mg daily for 3 days.

Failure to respond is an indication for antibody therapy, usually with antithymocyte globulin.

Question 36

Greater than ____mg/day of albuminuria represents frank proteinuria and more advanced renal disease

Answer 36

300 mg/24 h

Sustained - >1-2 g/day

Question 37

___________ glomerulonephritis demonstrates hypercellularity of mesangial and endothelial cells, glomerular infiltrates of PMNs, granular subendothelial immune deposits of IgG, IgM, C3, C4 , and C5–9, and subepithelial deposits

Answer 37

PSGN

Question 38

In PSGN In the first week of symptoms, ____ % of patients will have a depressed CH50 and decreased levels of C3 with normal levels of C4

Answer 38

90%

Question 39

Treatment for PSGN

Answer 39

Treatment is supportive, with control of hypertension, edema, and dialysis as needed.

Antibiotic treatment for active streptococcal infection should be given to patients and their cohabitants. There is no role for immunosuppressive therapy, even in the setting of crescents.

Question 40

Antibodies that that fix complement correlate best with the presence of renal disease in lupus nephritis

Answer 40

Anti-dsDNA

Hypocomplementemia is common in patients with acute lupus nephritis (70–90%) and declining complement levels may herald a flare.

Question 41

Class of Lupus nephritis that presents with mesangial hypercellularity with expansion of the mesangia matrix

Answer 41

Class II

Question 42

Class of Lupus nephritis that presents with focal endocapillary and extracapillary proliferation with focal subendothelial immune deposits and mild mesangial expansion

Answer 42

Class III

Question 43

Class of Lupus nephritis that presents with diffuse endocapillary and extracapillary proliferation with diffuse subendothelial immune deposits and mesangial alterations

Answer 43

Class IV

Current evidence suggests that inducing a remission with administration of high-dose steroids and either cyclophosphamide or mycophenolate mofetil for 2–6 months, followed by maintenance therapy with lower doses of steroids and mycophenolate mofetil or azathioprine, best balances the likelihood of successful remission with the side effects of therapy

Question 44

Class of Lupus nephritis that presents with thickened BM with diffuse subepithelial immune deposits

Answer 44

V

Patients with lupus nephritis class V, like patients with idiopathic membranous nephropathy (IMN), are predisposed to renal vein thrombosis and other thrombotic complications.

Question 45

Class of lupus nephritis with Global sclerosis of nearly all glomerular capillaries

Answer 45

VI

Renal transplantation in renal failure from lupus, usually performed after ~6 months of inactive disease, results in allograft survival rates comparable to patients transplanted for other reasons.

Question 46

Class of lupus nephritis with the most varied course

Answer 46

III

Question 47

Henoch-Schönlein purpura is distinguished clinically from IgA nephropathy by (4).

Answer 47

prominent systemic ssx, a younger age (<20 years old), preceding infection, and abdominal complaints

Question 48

Type I MPGN is associated with Hepatiti __ infection

Answer 48

B and C

Type I MPGN is immune complex–mediated and commonly associated with persistent hepatitis B and C, fungal and parasitic infections, SBE, autoimmune diseases such as lupus or cryoglobulinemia, or monoclonal gammopathies, including monoclonal gammopathy of renal significance (MGRS), where the only clinically apparent manifestations are in the kidney

Question 49

Primary responders are patients who have a complete remission ( of____ proteinuria) after a single course of prednisone; steroid-dependent patients relapse as their steroid dose is tapered.

Answer 49

<0.2 mg/24 h

Question 50

Response to steroids

Frequent relapsers have ____ relapses in ___ months following taper, and steroid-resistant patients fail to respond to steroid therapy.

Answer 50

two or more relapses in the 6 months

Question 51

Adults are not considered steroid-resistant until after ___ months of therapy.

Answer 51

4 months or 16 weeks

Question 52

First line therapy for MCD

Answer 52

Prednisone

Other immunosuppressive drugs, such as cyclophosphamide, chlorambucil, and mycophenolate mofetil, are saved for frequent relapsers, steroid-dependent patients, or steroidresistant patients.

Cyclosporine can induce remission, but relapse is also common when cyclosporine is withdrawn. The long-term prognosis in adults is less favorable when acute renal failure or steroid resistance occurs.

Electron microscopy, consistently demonstrates an effacement of the foot processes supporting the epithelial podocytes with weakening of slit-pore membranes. The pathogenesis of this lesion is unclear

Question 53

Treatment of patients with primary FSGS should include

Answer 53

inhibitors of the renin-angiotensin system

Patients with primary FSGS with nephrotic-range proteinuria can be treated with steroids but respond far less often and after a longer course of therapy than patients with MCD. Proteinuria remits in only 20–45% of patients receiving a course of steroids over 6–12 months

Question 54

The treatment of secondary FSGS typically involves

Answer 54

treating the underlying cause and controlling proteinuria.

Question 55

GN that has the highest reported incidences of renal vein thrombosis, pulmonary embolism, and deep-vein thrombosis.

Answer 55

MGN AKA membranous nephropathy

Prophylactic anticoagulation is controversial but has
been recommended for patients with hypoalbuminemia

Question 56

Therapy with immunosuppressive drugs is also recommended for patients with primary MGN and persistent proteinuria ____ g/day

Answer 56

(>3.0 g/24 h).

Question 57

What microscopic finding is a sensitive indicator for the presence of diabetes but correlates poorly with the presence or absence of clinically significant nephropathy.

Answer 57

Thickening of the GBM

Mesangial expansion: correlates with clinical manifestation of DM nephropathy

Question 58

Microalbuminuria appears ____ years after the onset of diabetes.

Answer 58

5–10

Morphologic changes = 1-2 yrs

Question 59

More than ___% of patients with type 1 diabetes and nephropathy have diabetic retinopathy

Answer 59

90%

so the absence of retinopathy in type 1 patients with proteinuria should prompt consideration of a diagnosis other than diabetic nephropathy

Question 60

There is a significant correlation between the presence of retinopathy and the presence of __________ nodules .

Answer 60

Kimmelstiel-Wilson

Question 61

Characteristic lesion of HIVAN

Answer 61

The lesion in HIVAN is FSGS, characteristically revealing a collapsing glomerulopathy

Question 62

Hydronephrosis may be absent on ultrasound when obstruction is less than ____ in duration or associated with volume contraction, staghorn calculi, retroperitoneal fibrosis, or infiltrative renal disease.

Answer 62

48 h

Ultrasonography is ~90% specific and sensitive for detection of hydronephrosis. False-positive results are associated with diuresis, renal cysts, or the presence of an extrarenal pelvis, a normal congenital variant.

Question 63

Type of stone not influenced by pH

Answer 63

Calcium Oxalate

Question 64

Uric acid stones form only when the urine pH is consistently _____ , whereas calcium phosphate stones are more likely to form when the urine pH is _____ .

Answer 64

≤5.5 or lower

≥6.5or higher

Cysteine solubility is increased when pH is inc

Question 65

Size of stone with low probability of spontaneous passage

Answer 65

> = 6mm

Question 66

The “gold standard” diagnostic test is ____ for urolithiasis

Answer 66

helical CT without contrast.

Question 67

Urine volume needed to lessen risk of stone formation

Answer 67

> 2L/day

<1 L/day = more than 2x risk

Question 68

______ also known as infection stones or triple-phosphate stones, form only when the upper urinary tract is infected with urease-producing bacteria such as Proteus mirabilis, Klebsiella pneumoniae, or Providencia species.

Answer 68

Struvite stones

Question 69

Cystine stones may be treated with medication that covalently binds to cystine like ______ and a medication that raises urine pH.

Answer 69

eg tiopronin or penicillamine

Tiopronin is the preferred choice due to its better adverse event profile.

The preferred alkalinizing agent to achieve a urine pH of 7.5 is potassium citrate or bicarbonate as sodium salts may increase cystine excretion

Question 70

Preferred alkalinizing agent for cystine stones

Answer 70

The preferred alkalinizing agent to achieve a urine pH of 7.5 is potassium citrate or bicarbonate as sodium salts may increase cystine excretion

Question 71

Pentad for TTP

Answer 71

MAHA, thrombocytopenia, neurologic symptoms, fever, and renal failure.

Question 72

Which has deficiency of ADAMST13? HUS or TTP?

Answer 72

TTP

The treatment of adult TTP with ADAMTS13 antibodies is daily plasmapheresis, which can be lifesaving. Plasmapheresis with fresh frozen plasma is given until the platelet count rises, but in relapsing patients, it normally is continued well after the platelet count improves. There is an anecdotal role in relapsing patients for using splenectomy, steroids, immunosuppressive drugs, bortezomib, or rituximab.

Patients without antibodies and a genetic deficiency of ADAMTS13 production can be treated with fresh frozen plasma alone.

Patients with Shiga toxin–mediated HUS are not given antibiotics and are treated with supportive care because antibiotics are thought to accelerate the release of the toxin and the diarrhea is usually self-limited. Patients with complement-mediated TMA/HUS are treated with eculizumab, an anticomplement therapy.

Question 73

First line therapy for scleroderma renal crisis

Answer 73

ACE-inhibition

Question 74

____ and _____ account for ~90% of cases of acute intrinsic renal failure

Answer 74

Ischemic and toxic Acute tubular necrosis (ATN)

Question 75

BUN: crea ratio of prerenal azotemia

Answer 75

> 20:1

Question 76

Causes of hypercoagulable state in nephrotic syndrome

Answer 76

urinary losses of antithrombin III
reduced proteins S and C
hyperfibrinogenemia
enhanced platelet aggregation.

Question 77

Cause of hyperlipidemia in nephrotic syndrome

Answer 77

inc hepatic lipoprotein synthesis.

Question 78

Hematuria with dysmorphic RBCs, RBC casts, and protein excretion > ____mg/day is virtually diagnostic of glomerulonephritis.

Answer 78

> 500 mg/d

RBC casts form as RBCs that enter the tubule fluid and become trapped in a cylindrical mold of gelled Tamm-Horsfall protein.

Question 79

Recommended as the best method for distinguishing between central and nephrogenic diabetes insipidus.

Answer 79

plasma AVP level

Question 80

AVP secretion is stimulated as systemic osmolality increases above a threshold level of ____

Answer 80

~285 mOsm/kg

. Thirst and thus water ingestion are also activated at ~285 mOsm/kg, beyond which there is an equivalent linear increase in the perceived intensity of thirst as a function of circulating osmolality

Question 81

Serum uric acid is often low (<_____) in patients with SIAD

Answer 81

4 mg/dL

in contrast, patients with hypovolemic hyponatremia will often be hyperuricemic, due to a shared activation of proximal tubular Na+-Cl– and urate transport

Question 82

Most common malignancy associated with SIADH

Answer 82

small cell lung CA

Question 83

Overly rapid correction of hyponatremia (>________ in 24h and ____ in 48h) is also associated with a disruption in integrity of the bloodbrain barrier, allowing the entry of immune mediators that may contribute to demyelination.

Answer 83

> 8–10 mM in 24 h or 18 mM in 48 h

Question 84

_______ has long been a cornerstone of the therapy of chronic hyponatremia.

Answer 84

Water deprivation

chronic hyponat duration > 48h

Question 85

The urine-to-plasma electrolyte ratio (urinary [Na+] + [K+]/plasma [Na+]) can be exploited as a quick indicator of electrolyte-free water excretion;
o patients with a ratio of >1 should be more aggressively restricted _______
o those with a ratio of ~1 should be restricted to _______,
o those with ratio <1 should be restricted to _____

Answer 85

(<500 mL/d)
500–700 mL/d
1 L/d

Question 86

________ is perhaps most appropriate for the management of significant and persistent SIAD (e.g., in small-cell lung carcinoma) that has not responded to water restriction and/or oral furosemide and salt tablets

Answer 86

Oral tolvaptan

Many patients with SIAD respond to combined therapy with oral furosemide, 20 mg twice a day (higher doses may be necessary in renal insufficiency), and oral salt tablets; furosemide serves to inhibit the renal countercurrent mechanism and blunt urinary concentrating ability, whereas the salt tablets counteract diuretic-associated natriuresis.

Question 87

Treatment of acute symptomatic hyponatremia should include hypertonic 3% saline (513 mM) to acutely increase plasma Na+ concentration by _____ to a total of ____; this modest increase is typically sufficient to alleviate severe acute symptoms

Answer 87

1–2 mM/h
4–6 mM

A bolus of 100 mL of hypertonic saline is more effective than an infusion, rapidly improving both serum sodium and mental status

The rate of correction should be comparatively slow in chronic
hyponatremia (<6-8 mM in the first 24 h and <6 mM each subsequent 24h), so as to avoid ODS; lower target rates are appropriate in patients at particular risk for ODS, such as alcoholics or hypokalemic patients.

Question 88

__________ is the most frequent manifestation of hypernatremia

Answer 88

Altered mental status

ranging from mild confusion and lethargy to deep coma.

Question 89

Patients with NDI will fail to respond to DDAVP, with a urine osmolality that increases by __% or < ____mOsm/kg from baseline, in combination with a normal or high circulating AVP level

Answer 89

<50%
< 150 mOsm/kg

Question 90

A rare exception to the slow correction of hypernatremia is patients with acute hypernatremia (<48 h) due to sodium loading, who can safely be corrected rapidly at a rate of _____

Answer 90

1 mM/h

It is imperative to correct hypernatremia slowly to avoid cerebral edema, typically replacing the calculated free water deficit over 48 h. Notably, the plasma Na+ concentration should be corrected by no more than 10 mM/d, which may take longer than 48 h in patients with severe hypernatremia (>160 mM).

Question 91

Class of diuretics that may reduce polyuria due to NDI, ostensibly by inducing hypovolemia and increasing proximal tubular water reabsorption.

Answer 91

Thiazides

Question 92

Random testing of plasma renin activity (PRA) and aldosterone is a helpful screening tool in hypokalemic and/or hypertensive patients, with an aldosterone:PRA ratio of ____ suggestive of primary hyperaldosteronism.

Answer 92

> 50

Question 93

Critical diagnostic test in Giterlman vs Barter syndrome

Answer 93

urinary calcium excretion

Patients with GS are uniformly hypomagnesemic and exhibit marked hypocalciuria (hece hypercalcemic), rather than the hypercalciuria typically seen in BS

Question 94

ECG findings are most marked when serum K+ is <_____

Answer 94

2.7mmol/L

Question 95

Urine K value that will differentiate extrarenal from renal losses

Answer 95

< 15 mmol / day for extrarenal losses

Question 96

TTKG in hypokalemia level that connotes inc K secretion

Answer 96

> 4

Question 97

TTKG level in hypokalemia that connotes INCREASED tubular flow

Answer 97

< 2

2bular

Question 98

Urine calcium/crea for Barters

Answer 98

> 0.20

B for bente

Question 99

Urine calcium/crea for Gitelman

Answer 99

< 0.15

Question 100

Classically, the ECG manifestations in hyperkalemia progress from tall peaked T waves (_____), to a loss of P waves (____) to a widened QRS complex (____), and, ultimately, a to a sine wave pattern ( )

Answer 100

5.5–6.5 mM (t wave)
6.5–7.5 mM (loss of p wave)
7.0–8.0 mM ( QRS)
>8.0 mM (sine)

Question 101

Electrolyte imblances that may potentiate digoxin

Answer 101

Hypokalemia and hypercalcemia

Question 102

In hyperkalemic patients with glucose concentrations of ≥ _____mg/dL, insulin should be administered without glucose, again with close monitoring of glucose concentrations

Answer 102

200–250

Question 103

TTKG level in hyperkalemia that connotes reduced tubular flow

Answer 103

> 8

Question 104

TTKG level in hyperkalemia that connotes decreased distal K secretion

Answer 104

< 5

Question 105

Drug that you should give if TTKG < 5 in hyperkalemia to test for tubular resistance

Answer 105

Fludrocortisone

F-ive, F-ludrocortisone

Question 106

Hypercalcemia associated with granulomatous disease (e.g., sarcoidosis) or lymphomas is caused by ___________

Answer 106

enhanced conversion of 25(OH)D to the potent 1,25(OH)2 D.

Question 107

The first step in the diagnostic evaluation of hyper- or hypocalcemia is to ensure that ____________

Answer 107

the alteration in serum calcium levels is not due to abnormal albumin concentrations

When serum albumin concentrations are reduced, a corrected calcium concentration is calculated by adding 0.2 mM (0.8 mg/dL) to the total calcium level for every decrement in serum albumin of 1.0 g/dL below the reference value of 4.1 g/dL for albumin, and, conversely, for elevations in serum albumin

Question 108

Chronic hypercalcemia is most commonly caused by __________ , as opposed to the second most common etiology of hypercalcemia, an underlying ______.

Answer 108

primary hyperparathyroidism
malignancy

Question 109

Initial therapy of significant hypercalcemia begins with ________

Answer 109

volume expansion because hypercalcemia invariably leads to dehydration

4–6 L of IV saline may be required over the first 24 h, keeping in mind that underlying comorbidities may require the use of loop diuretics to enhance Na and Ca excretion

Question 110

In patients with 1,25(OH)2 D-mediated hypercalcemia, ______ are the preferred therapy, as they decrease 1,25(OH)2 D production.

Answer 110

glucocorticoids

Question 111

Formula for plasma osmolality

Answer 111

Plasma osmolality is calculated according to the following expression: Posm = 2Na + Glu + BUN (all in mmol/L), or, using conventional laboratory values in which glucose and BUN are expressed in milligrams per deciliter: Posm = 2Na+ Glu/18 + BUN/2.8.

When the measured osmolality exceeds the calculated osmolality by >10–15 mmol/kg H2 O, one of two circumstances prevails. Either the serum sodium is spuriously low, as with hyperlipidemia or hyperproteinemia (pseudohyponatremia), or osmolytes other than sodium salts, glucose, or urea have accumulated in plasma

Question 112

Type of RTA that is most often due to generalized proximal tubular dysfunction manifested by glycosuria, generalized aminoaciduria, and phosphaturia

Answer 112

Proximal RTA (type 2 RTA)

Associated with Fanconi syndrome

Tx: Alkali supplementatio + K and Vit D

Question 113

Type of RTA with the typical findings including hypokalemia, a non-AG metabolic acidosis, low urinary NH4 + excretion (positive UAG, low urine [NH4 +]), and inappropriately high urine pH (pH > 5.5).

Answer 113

classic distal RTA (type 1 RTA)

Remember low urinary NH4 exretion!!!

Most patients have hypocitraturia and hypercalciuria, so nephrolithiasis, nephrocalcinosis, and bone disease are common.

bONE (b1)

Tx: Alkali supplementation + Citrate

Question 114

Type of RTA in which hyperkalemia is disproportionate to the reduction in (GFR) because of coexisting dysfunction of potassium and acid secretion.

Answer 114

distal RTA (type 4 RTA)

Most common form

Question 115

______ syndrome results from an inherited gain of function mutation of genes that regulate the collecting duct Na+ channel (ENaC).

Answer 115

Liddle’s

Question 116

most common acid-base disturbance in critically ill patients and, when severe, portends a poor prognosis

Answer 116

Chronic respiratory alkalosis

The compensatory reduction in plasma [HCO3 – ] is so effective in chronic respiratory alkalosis that the pH may not decline significantly from the normal value. Therefore, chronic respiratory alkalosis is the only acid-base disorder for which compensation can return the pH to the normal value

Question 117

the most common cause of drug-induced respiratory alkalosis as a result of direct stimulation of the medullary chemoreceptor

Answer 117

Salicylates

Question 118

mechanism that predominantly mediates potassium balance in CKD

Answer 118

Aldosterone dependent secretion in the
distal nephron

Question 119

complication is prevented by supplemental bicarbonate in CKD

Answer 119

protein catabolism

Question 120

Target blood pressure for patients with CKD and concomitant proteinuria?

Answer 120

<130/80

Question 121

most common organisms implicated in peritonitis in px undergoing peritoneal dialysis

Answer 121

G+ cocci

Question 122

main feature distinguishing pyelonephritis from cystitis?

Answer 122

fever

Question 123

What is the threshold for diagnosing asymptomatic bacteriuria in urine culture expressed in bacterial CFU/mL?

Answer 123

10^5

Question 124

type of AKI caused by cyclosporine

Answer 124

pre-renal

same with ACE I and NSAIDs

PPI = intrinsic

Question 125

portion of the kidney is particularly
susceptible to ischemic damage?

Answer 125

outer medulla

and S3 segment

Question 126

PSGN usually develops
After _____ weeks post impetigo/skin infection
After _____weeks post strep pharyngitis

Answer 126

2-6 weeks
1-3 weeks

Question 127

Most common cause of nephrotic syndrome in the elderly

Answer 127

MGN

Biopsy: uniform thickening of the basement membrane along the peripheral capillary LOOPSon light microscopy, diffuse granular deposits of IgG and C3 on IF and subepithelial electron-dense deposits on EM

Question 128

urine osmolality of pre renal AKI

Answer 128

> 500

Question 129

urine crea/ plasma crea ratio of pre renal AKI

Answer 129

> 40

Question 130

Vomiting, nausea, confusion, and seizures, usually at plasma Na+ concentration _____

Answer 130

<125 mM

Question 131

The ultimate “gold standard” for the diagnosis of hypovolemic hyponatremia is __________

Answer 131

the demonstration that plasma Na+ concentration corrects after hydration with normal saline

Question 132

Causes of low FeNa aside from pre-renal AKI

Answer 132

Rhabdomyolysis
Sepsis
Hemolysis
CIN

-sis + CIN

Question 133

Myeloma light chains can also cause AKI by

Answer 133

Binding to Tamm-Horsfall protein to form obstructing intratubular casts

Question 134

The presence of hematuria and RBC casts on urinalysis in the setting of azotemia, oliguria, edema and hypertension point to the possibility of which major renal syndrome?

Answer 134

Acute nephritis

Question 135

If BM thickening is a sensitive indicator of DM but does not corrrelate with nephropathy, what histologic finding correlates well with DM nephropathy?

Answer 135

Mesangial expansion

Question 136

Formula for corrected anion gap

Answer 136

CorrectedAnionGap=MeasuredAnionGap+2.5×(4.0−SerumAlbumin(g/dL))

*some sources use 4.5 as normal value for albumin

Question 137

What is the mechanism of Vancomycin in causing acute kidney injury?

Answer 137

Intratubular obstruction

** same with acyclovir

Question 138

Vitamin C supplementation increases risk for what kind of stone formation

Answer 138

CaOx

Question 139

What is the recommended urine pH for uric acid stones

Answer 139

6.5

Question 140

What are the containdications to kidney biopsy?

Answer 140

Contraindications for kidney biopsy
Not advisable for patients with bilaterally small
kidneys:
* Technically difficult and higher chances of bleeding
* Scarred tissue will not show underlying disease
* Disease-specific therapy no longer useful

Other contraindications:
* Uncontrolled hypertension
* Active UTI
* Bleeding diathesis (including anticoagulation)
* Severe obesity

Question 141

A urine osmolality <___mOsm/kg is suggestive of polydipsia

Answer 141

100

Question 142

from the earliest stages of microalbuminuria, it usually takes ___ years to reach ESRD.

Answer 142

10–20

Question 143

GNs that presents with hypocomplementenemia (3)

Answer 143

MPGN
Lupus nephritis
PSGN

** extra: cryloglobulinemia also has decreased C4 + positive RF

Question 144

Type of cast seen in pre renal AKI

Answer 144

granular/hyaline

Question 145

Most common type of stone

Answer 145

Calcium oxalate

Question 146

The majority of calcium oxalate stones grow on calcium phosphate at the tip of the renal papilla AKA

Answer 146

(Randall’s plaque).

Question 147

Effect of pH on citrate reabsorption

Answer 147

Citrate reabsorption is influenced by the intracellular pH of proximal tubular cells. Metabolic acidosis, including that due to higher animal flesh intake, will lead to a reduction in citrate excretion by increasing reabsorption of filtered citrate.

Question 148

This test serves as the cornerstone on which therapeutic recommendations are based for px with urolithiasis

Answer 148

The results from 24-h urine collections serve as the cornerstone on which therapeutic recommendations are based.

At least 2 samples needed

The following factors should be measured: total volume, calcium, oxalate, citrate, uric acid, sodium, potassium, phosphorus, pH, and creatinine. When available, the calculated supersaturation is also informative.

Question 149

Risk factors for caox stones

Answer 149

Risk factors for calcium oxalate stones include higher urine calcium, higher urine oxalate, and lower urine citrate

Individuals with higher urine calcium excretion tend to absorb a higher percentage of ingested calcium. Nevertheless, dietary calcium restriction is not beneficial and, in fact, is likely to be harmful. Excessive calcium intake (>1200 mg/d) should be avoided

Question 150

Mediation used to tx hypertension that can decrease Caox recurrence

Answer 150

A thiazide diuretic, in doses higher than those used to treat hypertension, can substantially lower urine calcium excretion. Several randomized controlled trials have demonstrated that thiazide diuretics, most commonly chlorthalidone, can reduce calcium oxalate stone recurrence by ~50%.

Question 151

T/F
In px with urinary tract obstruction, pain severity is influenced more by the rate at which distention develops than by the degree of distention.

Answer 151

true

Flank pain, the symptom that most commonly leads to medical attention, is due to distention of the collecting system or renal capsule. Pain severity is influenced more by the rate at which distention develops than by the degree of distention.

Question 152

T/F
Partial bilateral UTO often results in acquired distal renal tubular acidosis, hypokalemia, and renal salt wasting

Answer 152

False
Partial bilateral UTO often results in acquired distal renal tubular acidosis, HYPERkalemia, and renal salt wasting

Question 153

Fluid of choice for post obstructive diuresis

Answer 153

. Often replacement with 0.45% saline is required

Question 154

Management of cardiorenal syndrome

Answer 154

Continued use of diuretic therapy may be associated with a reduction in glomerular filtration rate and a worsening of the cardiorenal syndrome when right-sided filling pressures remain elevated.

In patients in the late stages of disease characterized by profound low cardiac output state, inotropic therapy or mechanical circulatory support has been shown to preserve or improve renal function in selected individuals in the short term until more definitive therapy such as assisted circulation or cardiac transplantation is implemented

Question 155

Difference between Type 1 vs Type 2 HRS

Answer 155

Type 1 HRS is characterized by a progressive impairment in renal function and a significant reduction in creatinine clearance within 1–2 weeks of presentation.

Type 2 HRS is characterized by a reduction in glomerular filtration rate with an elevation of serum creatinine level, but it is stable and is associated with a better outcome than that of type 1 HRS

HRS requires exclusion of other causes of acute renal failure, most notably volume depletion

Question 156

Management of HRS

Answer 156

Diuretics should be stopped, and infusion of albumin 1 g/kg per day is recommended. Treatment is with vasoconstrictors such as terlipressin or low-dose norepinephrine (requires intensive care unit monitoring).

Midodrine, an α-agonist, along with octreotide and intravenous albumin are also commonly used in the United States.

The best therapy for HRS is liver transplantation; recovery of renal function is typical in this setting. In patients with either type 1 or type 2 HRS, the prognosis is poor unless transplant can be achieved within a short period of time.

Question 156

Hypotension is the most common acute complication of hemodialysis, particularly among patients with _______

Answer 156

diabetes mellitus

Excessively rapid fluid removal (>13 mL/kg per h) should be avoided, as rapid fluid removal has been associated with adverse outcomes, including cardiovascular deaths.

Midodrine, an oral selective α1 adrenergic agent, has been advocated by some practitioners, although there is insufficient evidence of its safety and efficacy to support its routine use

Question 157

Difference between two dialyzer reaction types

Answer 157

Dialyzer reactions can be divided into two types, A and B. Type A reactions are attributed to an IgEmediated intermediate hypersensitivity reaction to ethylene oxide used in the sterilization of new dialyzers. This reaction typically occurs soon after the initiation of a treatment (within the first few minutes) and can progress to full-blown anaphylaxis if the therapy is not promptly discontinued. Treatment with steroids or epinephrine may be needed if symptoms are severe.

The type B reaction consists of a symptom complex of nonspecific chest and back pain, which appears to result from complement activation and cytokine release

Question 158

Difference between CAPD vs CCPD peritoneal dialysis

Answer 158

In CAPD, dialysate is manually infused into the peritoneal cavity and exchanged three to five times during the day. A nighttime dwell is frequently instilled at bedtime and remains in the peritoneal cavity through the night.

In CCPD, exchanges are performed in an automated fashion, usually at night; the patient is connected to an automated cycler that performs a series of exchange cycles while the patient sleeps. The number of exchange cycles required to optimize peritoneal solute clearance varies by the peritoneal membrane characteristics; as with hemodialysis, solute clearance should be tracked to ensure dialysis “adequacy.”

Question 159

formal evaluation of peritoneal membrane characteristics that measures the transfer rates of creatinine and glucose across the peritoneal membrane

Answer 159

The peritoneal equilibrium test is a formal evaluation of peritoneal membrane characteristics that measures the transfer rates of creatinine and glucose across the peritoneal membrane

Question 160

major complications of peritoneal dialysis p

Answer 160

The major complications of peritoneal dialysis are peritonitis, catheter-associated nonperitonitis infections, weight gain and other metabolic disturbances, and residual uremia (especially among patients with little or no residual kidney function).

Question 161

How do you differentiate pre renal from renal cause of AKI based on FeNa, U/P ratio and urine osmolality

Answer 161

Question 162

How do you differentiate PSGN vs Iga nephropathy with regard to timing of pharyngitis?

Answer 162

Postinfectious GN is to be distinguished from synpharyngitic hematuria, another glomerular syndrome that frequently produces gross hematuria, a heavier excretion of red blood, which may appear to the patient as a frightening hemorrhage. The patient may present with this concern so it is important for the clinician to recognize that as little as 10–20 mL of blood will turn a liter of urine red.

Synpharyngitic hematuria, usually with a viral pharyngitis, is most often related to IgA nephropathy rather than postinfectious GN.

Another feature that distinguishes IgA nephropathy from postinfectious GN is that the former usually demonstrates normal circulating C3 complement as opposed to low complement in PIGN.

IgA nephropathy can cause chronic microhematuria or bouts of gross hematuria or can occur in association with other immunologic conditions including celiac disease, rheumatoid arthritis, reactive arthritis, and ankylosing spondylitis. IgA nephropathy and staphylococcal-associated GN are more common in Asian populations

Question 163

Acute allergic or immune interstitial nephritis (AIN) usually occurs __________ (duration) following exposure to an offending drug and may be associated with a rapid and potentially reversible loss of kidney function, which may occur in the setting of a change in dose or the restarting of a previously used medication

Answer 163

Acute allergic or immune interstitial nephritis (AIN) usually occurs 1 day to 2 weeks following exposure to an offending drug and may be associated with a rapid and potentially reversible loss of kidney function, which may occur in the setting of a change in dose or the restarting of a previously used medication.

Associated glomerular proteinuria sometimes occurs with the use of nonsteroidal anti-inflammatory drugs (NSAIDs) or ampicillin.
Clinically, there may be fever, rash, and eosinophilia; the last is typical for certain penicillins, fluoroquinolones, and some biologic cancer drugs that act as checkpoint inhibitors (CPIs) but is atypical for NSAIDs.

Question 164

most common cause of chronic interstitial nephritis

Answer 164

Perhaps the most common cause of chronic interstitial nephritis is prolonged analgesic use to treat chronic pain (not only NSAIDs but acetaminophen or combinations of phenacetin, aspirin, and caffeine) as part of the analgesic syndrome. T

Question 165

3 defining features of nephrotic syndrome

Answer 165

Nephrotic syndrome (NS) has three defining features: edema, hypoalbuminemia (<3.5 g/dL), and proteinuria >3.5 g/day.

The syndrome is often associated with lipid abnormalities such as a high LDL, low HDL, and lipiduria.

The urine may contain large tubular epithelial cells that are engulfed with the lipid in a recognizable shape under polarized light. These oval fat bodies may also contain cholesterol monohydrate crystals, which appear as Maltese crosses.

Question 166

A characteristic finding of rapid-onset hypoalbuminemia in NS is horizontal linear white lines in the nail bed, known as

Answer 166

A characteristic finding of rapid-onset hypoalbuminemia in NS is horizontal linear white lines in the nail bed, known as Muehrcke’s line

Question 167

Exception to the low sodium excretion in prerenal AKI

Answer 167

The fractional excretion of sodium is usually >1–2%, whereas in oliguric prerenal syndromes the fractional excretion of sodium is usually <1%. Exception to the low sodium excretion would be in the case of hyperchloremic metabolic alkalosis, where chloride is being conserved and sodium excreted with bicarbonate

Question 168

Stage of CKD in which the patient should be prepared and educated about transplant and dialysis

Answer 168

4

When the eGFR is <15–20 mL/min, the patient should already have had conversations about choices of eventual treatment and, if indicated, surgical preparation for peritoneal or hemodialysis

Question 169

Based on CPG 2018, Among CKD 5 patients on low-flux hemodialysis, ___ times a week hemodialysis may be recommended.

Answer 169

3 (4 hrs each session)

same with hi flux

Question 170

Based on CPG 2018, Initiation of hemodialysis at eGFR greater than ___ ml/min is not recommended among asymptomatic patients with CKD 5.

Answer 170

Initiation of hemodialysis at eGFR greater than 10 ml/min is not recommended among asymptomatic patients with CKD 5.

Question 171

Based on CPG 2018, Among CKD 5 patients with CHF, initiating hemodialysis at eGFR <__ml/min may be recommended.

Answer 171

15

if no CHF <10

Question 172

T/F
The mean GFR is lower in women than in men

Answer 172

True

Question 173

Diagnostic test for monitoring albuminuria

Answer 173

Measurement of albuminuria is also helpful for monitoring nephron injury and the response to therapy in many forms of CKD, especially chronic glomerular diseases. The cumbersome 24-h urine collection has been replaced by measurement of urinary albumin-to-creatinine ratio (UACR) in one and preferably several spot first-morning urine samples as a measure pointing to glomerular injury.

Even in patients with negative conventional urinary dipstick tests for protein, persistent UACR >2.5 mg/mmol (male) or >3.5 mg/mmol (female) on two to three occasions serves as a marker not only for early detection of primary kidney disease but for systemic microvascular disease as well.

Question 174

Leading causes of CKD

Answer 174

Diabetic nephropathy = #1
Glomerulonephritis
Hypertension-associated CKD (includes vascular and ischemic kidney disease and primary glomerular disease with associated hypertension)
Autosomal dominant polycystic kidney disease
Other cystic and tubulointerstitial nephropathy

Question 175

T/F thiazide diuretics may be used across all stages of CKD

Answer 175

False

Thiazide diuretics have limited utility in stages 3–5 CKD, such that administration of loop diuretics, including furosemide, bumetanide, or torsemide, may be needed

Question 176

Hyperparathyroidism stimulates bone turnover and leads to _________________. Bone histology shows abnormal osteoid, bone and bone marrow fibrosis, and, in advanced stages, the formation of bone cysts, sometimes with hemorrhagic elements so that they appear brown in color; hence, the term brown tumor.

Answer 176

Hyperparathyroidism stimulates bone turnover and leads to osteitis fibrosa cystica. Bone histology shows abnormal osteoid, bone and bone marrow fibrosis, and, in advanced stages, the formation of bone cysts, sometimes with hemorrhagic elements so that they appear brown in color; hence, the term brown tumor.

Question 177

CXR findings of low pressure pulmonary edema from CKD

Answer 177

A form of “low-pressure” pulmonary edema can also occur in advanced CKD, manifesting as shortness of breath and a “bat wing” distribution of alveolar edema fluid on chest x-ray. This finding can occur even in the absence of ECFV overload and is associated with normal or mildly elevated pulmonary capillary wedge pressure. This process has been ascribed to increased permeability of alveolar capillary membranes as a manifestation of the uremic state, and it responds to dialysis

Question 178

Causes of anemia in CKD

Answer 178

Question 179

Subtle clinical manifestations of uremic neuromuscular disease usually become evident at stage ___ CKD

Answer 179

3

Question 180

In women with CKD, estrogen levels are low, and menstrual abnormalities, infertility, and inability to carry pregnancies to term are common. When the GFR has declined to ~__ mL/min, pregnancy is associated with a high rate of spontaneous abortion, with only ~20% of pregnancies leading to live births, and pregnancy may hasten the progression of the kidney disease itself

Answer 180

40

Question 181

Most useful imaging study for CKD

Answer 181

The most useful imaging study is a renal ultrasound, which can verify the presence of two kidneys, determine if they are symmetric, provide an estimate of kidney size, and rule out renal masses and evidence of obstruction

Question 182

Which CCB has superior antiproteinuric and renoprotective effects

Answer 182

Among the calcium channel blockers, diltiazem and verapamil may exhibit superior antiproteinuric and renoprotective effects compared to the dihydropyridines.

Question 183

AKI staging

Answer 183

Question 184

Even in healthy adults, renal autoregulation usually fails once the systolic blood pressure falls below ____ mmHg

Answer 184

There is a limit, however, to the ability of these counterregulatory mechanisms to maintain GFR in the face of systemic hypotension. Even in healthy adults, renal autoregulation usually fails once the systolic blood pressure falls below 80 mmHg

Question 185

most common causes of intrinsic AKI

Answer 185

The most common causes of intrinsic AKI are sepsis, ischemia, and nephrotoxins, both endogenous and exogenous

Question 186

markedly elevated intraabdominal pressures, usually >__ mmHg, lead to renal vein compression and reduced GFR

Answer 186

20

Question 187

the gold standard for direct visualization of the renal vasculature and is important for the diagnosis of renal artery stenosis, large vessel vasculitis, fibromuscular disease, or renal vein obstruction.

Answer 187

Renal angiography is the gold standard for direct visualization of the renal vasculature and is important for the diagnosis of renal artery stenosis, large vessel vasculitis, fibromuscular disease, or renal vein obstruction.

Question 188

How does aminoglycosides and amp B cause intrinsic AKI?

Answer 188

Aminoglycosides and amphotericin B both cause tubular necrosis. Same with cisplatin and carboplatin

Nonoliguric AKI accompanies 10–30% of courses of aminoglycoside antibiotics, even when plasma levels are in the therapeutic range.

Aminoglycosides are freely filtered across the glomerulus and then accumulate within the renal cortex, where concentrations can greatly exceed those of the plasma. AKI typically manifests after 5–7 days of therapy and can present even after the drug has been discontinued. Hypomagnesemia is a common finding

Amphotericin B causes renal vasoconstriction from an increase in tubuloglomerular feedback as well as direct tubular toxicity mediated by reactive oxygen species. Nephrotoxicity from amphotericin B is dose and duration dependent. This drug binds to tubular membrane cholesterol and introduces pores. Clinical features of amphotericin B nephrotoxicity include polyuria, hypomagnesemia, hypocalcemia, and nongap metabolic acidosis.

Question 189

Electrolyte abnormalities associated with ifosfamide

Answer 189

Ifosfamide may cause hemorrhagic cystitis and tubular toxicity, manifested as type II renal tubular acidosis (Fanconi syndrome), polyuria, hypokalemia, and a modest decline in GFR

Question 190

MOA of AKI from ethylene glycol

Answer 190

Ethylene glycol, present in automobile antifreeze, is metabolized to oxalic acid, glycolaldehyde, and glyoxylate, which may cause AKI through direct tubular injury and tubular obstruction

Think of ethylene glycol if + oxalate crystals and AKI + HAGMA

Question 191

Treatment for rhabdomyolysis

Answer 191

Early and aggressive volume repletion is mandatory in patients with rhabdomyolysis, who may initially require 10 L of fluid per day. Alkaline fluids (e.g., 75 mmol/L sodium bicarbonate added to 0.45% saline) may be beneficial in preventing tubular injury and cast formation, but carry the risk of worsening hypocalcemia.
Diuretics may be used if fluid repletion is adequate but unsuccessful in achieving urinary flow rates of 200–300 mL/h. There is no specific therapy for established AKI in rhabdomyolysis, other than dialysis in severe cases or general supportive care to maintain fluid and electrolyte balance and tissue perfusion

Question 192

Metabolic acidosis is generally not treated unless severe (pH <____ AND serum bicarbonate <___ mmol/L).

Answer 192

Metabolic acidosis is generally not treated unless severe (pH <7.20 and serum bicarbonate <15 mmol/L).

Question 193

T/F Anemia in AKI can be tx by erythropoiesis-stimulating agents

Answer 193

The anemia seen in AKI is usually multifactorial and is not improved by erythropoiesis-stimulating agents, due to their delayed onset of action and the presence of bone marrow resistance in critically ill patients

ESA only in CKD

Question 194

More severe hypercalcemia (>_____mg/dL), particularly if it develops acutely, may result in lethargy, stupor, or coma, as well as gastrointestinal symptoms (nausea, anorexia, constipation, or pancreatitis)

Answer 194

More severe hypercalcemia (>12–13 mg/dL), particularly if it develops acutely, may result in lethargy, stupor, or coma, as well as gastrointestinal symptoms (nausea, anorexia, constipation, or pancreatitis)

Question 195

Although there are many potential causes of hypocalcemia, _____________ are the most common etiologies

Answer 195

impaired PTH production and impaired vitamin D production

Hypoparathyroidism is a cardinal feature of autoimmune endocrinopathies

A suppressed (or “inappropriately low”) PTH level in the setting of hypocalcemia establishes absent or reduced PTH secretion (hypoparathyroidism) as the cause of the hypocalcemia. Further history will often elicit the underlying cause (i.e., parathyroid agenesis vs destruction)

Question 196

Carpal spasm may be induced by inflation of a blood pressure cuff to ___ mmHg above the patient’s systolic blood pressure for 3 min (Trousseau’s sign).

Answer 196

Carpal spasm may be induced by inflation of a blood pressure cuff to 20 mmHg above the patient’s systolic blood pressure for 3 min (Trousseau’s sign).

Question 197

The MDRD equation is better correlated with true GFR when the GFR is <____ mL/min per 1.73 m2 .

Answer 197

The MDRD equation is better correlated with true GFR when the GFR is <60 mL/min per 1.73 m2 .

Question 198

Patients with atheroembolic acute renal failure often have a normal urinalysis, but the urine may contain

Answer 198

eosinophils and casts

Question 199

Next step when px with hematuria presents with proteinuria

Answer 199

Question 200

The dipstick measurement detects only albumin and gives false-positive results at pH

Answer 200

The dipstick measurement detects only albumin and gives false-positive results at pH >7.0 or when the urine is very concentrated or contaminated with blood.

Question 201

Hematuria is defined as ______ RBCs per high-power field (HPF) and can be detected by dipstick

Answer 201

Hematuria is defined as two to five RBCs per high-power field (HPF) and can be detected by dipstick

Gross hematuria with blood clots usually is not an intrinsic renal process; rather, it suggests a postrenal source in the urinary collecting system

Question 202

1st diagnostic test when px presents with polyuria

Answer 202

If the urine volume is >3 L/d and urine osmolality is >300 mosmol/L, a solute diuresis is clearly present and a search for the responsible solute(s) is mandatory

Poorly controlled diabetes mellitus with glucosuria is the most common cause of a solute diuresi

Question 203

Winter’s equation

Answer 203

Paco2 = (1.5 × [HCO3 −]) + 8 ± 2 (Winter’s equation)

Question 204

Cause of HAGMA

Answer 204

An increase in the AG is most often due to an increase in unmeasured anions but, less commonly, may be due to a decrease in unmeasured cations (calcium, magnesium, potassium).

Question 205

Indications for bicarbonate therapy in DKA

Answer 205

Bicarbonate therapy in diabetic ketoacidosis (DKA) is reserved for adult patients with severe acidemia (pH <7.00) and/or evidence of shock. In such circumstances, bicarbonate may be administered IV, as a slow infusion of 50 meq of NaHCO3 diluted in 300 mL of a saline solution, over 30–45 min, during the initial 1–2 h of therapy. Bolus administration should be avoided.

Question 205

4 principal causes of HAGMA

Answer 205

There are four principal causes of a high-AG acidosis: (1) lactic acidosis, (2) ketoacidosis, (3) ingested toxins, and (4) acute and chronic kidney failure

Question 206

2 types of lactic acidosis

Answer 206

An increase in plasma l-lactate may be secondary to poor tissue perfusion (type A)—circulatory insufficiency (shock, cardiac failure), severe anemia, mitochondrial enzyme defects, and inhibitors (carbon monoxide, cyanide)—or to aerobic disorders (type B)—malignancies, nucleoside analogue reverse transcriptase inhibitors in HIV, diabetes mellitus, renal or hepatic failure, thiamine deficiency, severe infections (cholera, malaria), seizures, or drugs/toxins (biguanides, ethanol, and the toxic alcohols: ethylene glycol, methanol, or propylene glycol)

Question 207

Treatment for ethylene glycol toxicity

Answer 207

This includes the prompt institution of IV isotonic fluids, thiamine and pyridoxine supplements, fomepizole, and usually, hemodialysis. Both fomepizole and ethanol compete with EG for metabolism by alcohol dehydrogenase. Fomepizole (4-methylpyrazole; 15 mg/kg IV over 30 min as a loading dose, then 10 mg/kg for four doses every 12 h) is the agent of choice and offers the advantages of a predictable decline in EG levels without excessive obtundation, as seen during ethyl alcohol infusion. Fomepizole should be continued until blood pH is normal or the osmolar gap is <10 mOsm/kg H2 O. Hemodialysis is indicated when the arterial pH is <7.3, a high-AG acidosis is present, the osmolar gap exceeds 20 mOsm/kg H2 O, or there is evidence of end organ damage such as CNS manifestations and kidney failure

Treatment of methanol intoxication is similar to that for EG intoxication, including general supportive measures, fomepizole, and hemodialysis

Question 208

Treatment for metab acidosis in CKD

Answer 208

Because of the association of metabolic acidosis in advanced CKD with muscle catabolism, bone disease, and more rapid progression of CKD, both the “uremic acidosis” of end-stage renal disease and the non-AG metabolic acidosis of stages 3 and 4 CKD require oral alkali replacement to increase and maintain the [HCO3 −] to a value >22 mmol/L. This can be accomplished with relatively modest amounts of alkali (1.0–1.5 mmol/kg body weight per day) and has been shown to slow the progression of CKD. Either NaHCO3 tablets (650-mg tablets contain 7.8 meq) or oral sodium citrate (Shohl’s solution) is effective. Moreover, addition of fruits and vegetables (citrate) to the diet may increase the plasma [HCO3 – ] and slow progression

Question 209

How do you differentiate NAGMA from RTA vs diarrhea?

Answer 209

Metabolic acidosis due to gastrointestinal losses with a high urine pH can be differentiated from RTA because urinary NH4 + excretion is typically low in RTA and high with diarrhea. Urinary NH4 + levels are not routinely measured by clinical laboratories but can be estimated by calculating the urine anion gap (UAG): UAG = [Na+ + K+]u – [Cl−]u . When [Cl−]u > [Na+ + K+]u , the UAG is negative by definition. This suggests that the urine ammonium level is appropriately increased, suggesting an extrarenal cause of the acidosis

Question 210

Fanconi syndrome is associated with what type of RTA?

Answer 210

Proximal RTA (type 2 RTA) is most often due to generalized proximal tubular dysfunction manifested by glycosuria, generalized aminoaciduria, and phosphaturia (Fanconi syndrome).

Question 211

Type of RTA associated with nephrolithiasis and nephrocalcinosis

Answer 211

The typical findings in acquired or inherited forms of classic distal RTA (type 1 RTA) include hypokalemia, a non-AG metabolic acidosis, low urinary NH4 + excretion (positive UAG, low urine [NH4 +]), and inappropriately high urine pH (pH >5.5). Most patients have hypocitraturia and hypercalciuria; nephrolithiasis, nephrocalcinosis, and bone disease are common

Question 212

Type of RTA associated with hyperkalemia

Answer 212

In generalized distal RTA (type 4 RTA), hyperkalemia is disproportionate to the reduction in glomerular filtration rate (GFR) because of coexisting dysfunction of potassium and acid secretion. Urinary ammonium excretion is invariably depressed, and kidney function may be compromised secondary to diabetic nephropathy, obstructive uropathy, or chronic tubulointerstitial disease

Question 213

How do you correct potassium in Type 2 RTA

Answer 213

An oral solution of sodium and potassium citrate (citric acid 334 mg, sodium citrate 500 mg, and potassium citrate 550 mg per 5 mL) may be prescribed for this purpose (Virtrate or Cytra-3).

Question 214

In Type 1 RTA, which should be corrected first, hypokalemia or acidosis?

Answer 214

. In classical distal RTA (type 1), hypokalemia should be corrected first. When accomplished, alkali therapy with either sodium citrate (Shohl’s solution) or NaHCO3 tablets (650-mg tablets contain 7.8 meq) should be initiated to correct and maintain the serum [HCO3 – ] in the range of 24–26 meq/L. Type 1 RTA patients typically respond to chronic alkali therapy readily, and the benefits of adequate alkali therapy include a decrease in the frequency of nephrolithiasis, improvement in bone density, resumption of normal growth patterns in children, and preservation of kidney function in both adults and children

Question 215

how does hypokalemia cause alkalosis?

Answer 215

renal generation of NH4 + (ammoniagenesis) is upregulated directly by hypokalemia. Chronic K+ deficiency also upregulates the H+, K+- ATPases in the distal tubule and collecting duct to increase K+ absorption while simultaneously increasing H+ secretion.

Question 216

How do you correct metabolic alkalosis due to ECV contraction

Answer 216

Isotonic saline is recommended to reverse the alkalosis when ECFV contraction is present. If associated conditions, such as congestive heart failure, preclude infusion of isotonic saline, renal HCO3 − loss can be accelerated by administration of acetazolamide (125–250 mg IV), a carbonic anhydrase inhibitor, which is usually effective in patients with adequate renal function.

Question 217

Vasopressin secretion, water ingestion, and renal water transport collaborate to maintain human body fluid osmolality between _______

Answer 217

Vasopressin secretion, water ingestion, and renal water transport collaborate to maintain human body fluid osmolality between 280 and 295 mOsm/kg

Question 218

More reliable signs of hypovolemia on physical examination

Answer 218

On examination, diminished skin turgor and dry oral mucous membranes are less than ideal markers of a decreased ECFV in adult patients; more reliable signs of hypovolemia include a decreased jugular venous pressure (JVP), orthostatic tachycardia (an increase of >15–20 beats/min upon standing), and orthostatic hypotension (a >10–20 mmHg drop in blood pressure on standing).

Question 219

two key effectors in the defense of serum osmolality

Answer 219

Water intake and circulating AVP constitute the two key effectors in the defense of serum osmolality

Question 220

Causes of euvolemic hyponatremia

Answer 220

if UNa >20, renal losses

Question 221

Causes of hypervolemic hyponatremia

Answer 221

if UNa >20, renal losses

Question 222

T/F
The degree of hyponatremia provides an indirect index of the associated neurohumoral activation and is an important prognostic indicator in hypervolemic hyponatremia.

Answer 222

True

Question 223

Formula for corrected sodium in hyperglycemia

Answer 223

Serum glucose should also be measured; plasma Na+ concentration falls by ~1.6–2.4 mM for every 100-mg/dL increase in glucose, due to glucose-induced water efflux from cells; this “true” hyponatremia resolves after correction of hyperglycemia

Question 224

Therapy with vaptans must be initiated in a hospital setting, with a liberalization of fluid restriction (>___ L/d) and close monitoring of plasma Na+ concentration.

Answer 224

Therapy with vaptans must be initiated in a hospital setting, with a liberalization of fluid restriction (>2 L/d) and close monitoring of plasma Na+ concentration.

Abnormalities in liver function tests have been reported with chronic tolvaptan therapy; hence, the use of this agent should be restricted to <1–2 months.

Question 225

subset of px with highest risk of developing hypernatremia

Answer 225

Elderly individuals with reduced thirst and/or diminished access to fluids are at the highest risk of developing hypernatremia.

Question 226

Rate of correction of hypernatremia in adults

Answer 226

In critically ill adults, however, recent evidence does not indicate that rapid correction of hypernatremia is associated with a higher risk for mortality, seizure, alteration of consciousness, and/or cerebral edema. Given that restricting the rate of correction to <10 mM/d has no physiologic sequelae, it seems prudent to restrict correction in adults to this rate; however, should that rate be exceeded, hypernatremia does not need to be reinduced.

**sequelae more common in pedia px

Question 227

Majority of potassium is excreted via

Answer 227

urine (90%)

Question 228

TPP develops more frequently in patients of Asian or Hispanic origin; this shared predisposition has been linked to genetic variation in _____, a muscle-specific, thyroid hormone–responsive K+ channel.

Answer 228

TPP develops more frequently in patients of Asian or Hispanic origin; this shared predisposition has been linked to genetic variation in Kir2.6, a muscle-specific, thyroid hormone–responsive K+ channel.

Question 229

What beta lactams are associated with hypokaleia

Answer 229

High doses of penicillin-related antibiotics (nafcillin, dicloxacillin, ticarcillin, oxacillin, and carbenicillin) can increase obligatory K+ excretion by acting as nonreabsorbable anions in the distal nephron

Question 230

T/F licorice is associated with hyperkalemia

Answer 230

False. Hypokalemia

Recessive loss-of-function mutations in the 11βHSD-2 gene are thus associated with cortisol-dependent activation of the MLR and the syndrome of apparent mineralocorticoid excess (SAME), encompassing hypertension, hypokalemia, hypercalciuria, and metabolic alkalosis, with suppressed PRA and suppressed aldosterone. A similar syndrome is caused by biochemical inhibition of 11βHSD-2 by glycyrrhetinic/ glycyrrhizinic acid and/or carbenoxolone. Glycyrrhizinic acid is a natural sweetener found in licorice root, typically encountered in licorice and its many guises or as a flavoring agent in tobacco and food products. More recently, the antifungals itraconazole and posaconazole have been shown to inhibit 11βHSD-2, leading to hypertension and hypokalemia.

Question 231

Loss of the transport functions of the TALH and DCT nephron segments causes hereditary hypokalemic alkalosis and ______ and _______ respectively

Answer 231

Loss of the transport functions of the TALH and DCT nephron segments causes hereditary hypokalemic alkalosis and Bartter’s syndrome (BS) and Gitelman’s syndrome (GS), respectively

Question 232

When excessive activity of the sympathetic nervous system is thought to play a dominant role in redistributive hypokalemia what should be given to reduc the risk of rebound hyperkalemia

Answer 232

When excessive activity of the sympathetic nervous system is thought to play a dominant role in redistributive hypokalemia, as in TPP, theophylline overdose, and acute head injury, high-dose propranolol (3 mg/kg) should be considered; this nonspecific β-adrenergic blocker will correct hypokalemia without the risk of rebound hyperkalemia

Question 233

most important infectious cause of adrenal insufficiency

Answer 233

HIV has surpassed tuberculosis as the most important infectious cause of adrenal insufficiency

Question 234

How does brugada type 1 pattern from hyperkalemia differ from genetic brugada syndrome based on ecg?

Answer 234

Hyperkalemia can also cause a type I Brugada pattern in the electrocardiogram (ECG), with a pseudo–right bundle branch block and persistent coved ST-segment elevation in at least two precordial leads. This hyperkalemic Brugada’s sign occurs in critically ill patients with severe hyperkalemia and can be differentiated from genetic Brugada’s syndrome by an absence of P waves, marked QRS widening, and an abnormal QRS axis.

Question 235

Effect of hyperkalemia on pH

Answer 235

Hyperkalemia can cause metabolic acidosis

Question 236

First step in managing px with severe hyperkalemia

Answer 236

The recommended dose is 10 mL of 10% calcium gluconate (3–4 mL of calcium chloride), infused intravenously over 2–3 min with cardiac monitoring. The effect of the infusion starts in 1–3 min and lasts 30–60 min; the dose should be repeated if there is no change in ECG findings or if they recur after initial improvement. Hypercalcemia potentiates the cardiac toxicity of digoxin; hence, intravenous calcium should be used with extreme caution in patients taking this medication; if judged necessary, 10 mL of 10% calcium gluconate can be added to 100 mL of 5% dextrose in water and infused over 20–30 min to avoid acute hypercalcemia.

Question 237

What could be given to reduce hyperkalemia by means of Rapid reduction in plasma K+ concentration by redistribution into cells.

Answer 237

Insulin- Glucose
The recommended dose is 10 units of intravenous regular insulin followed immediately by 50 mL of 50% dextrose (D50W, 25 g of glucose total); the effect begins in 10–20 min, peaks at 30–60 min, and lasts for 4–6 h. Bolus D50W without insulin is never appropriate, given the risk of acutely worsening hyperkalemia due to the osmotic effect of hypertonic glucose. Hypoglycemia is common with insulin plus glucose; hence, this should be followed by an infusion of 10% dextrose at 50–75 mL/h, with close monitoring of plasma glucose concentration. In hyperkalemic patients with glucose concentrations of ≥200–250 mg/dL, insulin should be administered without glucose, again with close monitoring of glucose concentrations.

B2 agonists
β2 -Agonists, most commonly albuterol, are effective but underused agents for the acute management of hyperkalemia. Albuterol and insulin with glucose have an additive effect on plasma K+ concentration; however, ~20% of patients with ESRD are resistant to the effect of β2 -agonists; hence, these drugs should not be used without insulin. The recommended dose for inhaled albuterol is 10–20 mg of nebulized albuterol in 4 mL of normal saline, inhaled over 10 min; the effect starts at about 30 min, reaches its peak at about 90 min, and lasts for 2–6 h. Hyperglycemia is a side effect, along with tachycardia. β2 - Agonists should be used with caution in hyperkalemic patients with known cardiac disease.

Question 238

Nephritic syndrome with gross subcapsular hemorrhages with a “flea-bitten” appearance, and microscopy on renal biopsy reveals focal proliferation around foci of necrosis associated with abundant mesangial, subendothelial, and subepithelial immune deposits of IgG, IgM, and C3 .

Answer 238

Endocarditis-associated glomerulonephritis is typically a complication of SBE, particularly in patients who remain untreated for a long time, have negative blood cultures, or have right-sided endocarditis. Common comorbidities are valvular heart disease, intravenous drug use, hepatitis C, and diabetes mellitus. Glomerulonephritis is unusual in acute bacterial endocarditis because it takes 10–14 days to develop immune complex–mediated injury, by which time the patient has been treated, often with emergent surgery. Grossly, the kidneys in SBE have subcapsular hemorrhages with a “flea-bitten” appearance, and microscopy on renal biopsy reveals focal proliferation around foci of necrosis associated with abundant mesangial, subendothelial, and subepithelial immune deposits of IgG, IgM, and C3 . Commonly patients present with a clinical picture of RPGN and have crescents on biopsy.

Question 239

Treatment for endocarditis associated GN

Answer 239

Primary treatment is eradication of the infection with 4–6 weeks of antibiotics, and if accomplished expeditiously, the prognosis for renal recovery is good

Question 240

Pathophysiology of Goodpasture syndrome

Answer 240

Patients who develop autoantibodies directed against glomerular basement antigens frequently develop a glomerulonephritis termed antiglomerular basement membrane (anti-GBM) disease. When they present with lung hemorrhage and glomerulonephritis, they have a pulmonary-renal syndrome called Goodpasture’s syndrome.

Question 241

Treatment for Goodpasture syndrome

Answer 241

Prognosis at presentation is worse if there are >50% crescents on renal biopsy with advanced fibrosis, if serum creatinine is >5–6 mg/dL, if oliguria is present, or if there is a need for acute dialysis. Patients who present with hemoptysis should be treated for their lung hemorrhage, as it responds to plasmapheresis.

Treated patients with less severe disease typically respond to 8–10 treatments of plasmapheresis accompanied by oral prednisone and cyclophosphamide.

Maintenance therapy with low-dose immunosuppressants should be considered until antibody titers are negative. There are scarce data alternatively using rituximab, azathioprine, or mycophenolate mofetil. Kidney transplantation should wait for 6 months and until serum antibodies are undetectable.

Question 242

Scoring system with predictive value for IgA Nephropathy

Answer 242

Mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular interstitial fibrosis (T), and crescents (C) have predictive value as established by the Oxford Classification and the MEST-C score

Question 243

Treatment for IgA Nephropathy

Answer 243

There is no agreement on optimal treatment.

Both large studies that include patients with multiple glomerular diseases and small studies of patients with IgA nephropathy support the use of (ACE) inhibitors in patients with proteinuria or declining renal function.

In patients with persistent proteinuria after ACE inhibitor therapy, steroid treatment or other immunosuppressives have demonstrated conflicting results.

Tonsillectomy and fish oil have also been suggested in small studies to benefit select patients. When presenting as RPGN, patients typically receive steroids, cytotoxic agents, and plasmapheresis.

Question 244

Patients with this disease classically present with fever, purulent rhinorrhea, nasal ulcers, sinus pain, polyarthralgias/arthritis, cough, hemoptysis, shortness of breath, hematuria, and subnephrotic proteinuria; occasionally, there may be cutaneous purpura and mononeuritis multiplex.

Answer 244

Granulomatosis with Polyangiitis

Previously known as Wegeners

Biopsy of involved tissue will show a small-vessel vasculitis and adjacent noncaseating granulomas. Renal biopsies during active disease demonstrate segmental necrotizing glomerulonephritis without immune deposits and have been classified as focal, mixed, crescentic, or sclerotic

** if with no lung dse/ sinusitis –> MPA / Microscopic polyangitis

Question 245

small-vessel vasculitis that is associated with peripheral eosinophilia, cutaneous purpura, mononeuritis, asthma, and allergic rhinitis

Answer 245

EGPA

previously known as Churg Strauss

Question 246

Treatment for MPGN

Answer 246

treatment with inhibitors of the renin-angiotensin system is prudent.

Evidence supports the efficacy of treatment of primary MPGN with steroids, particularly in children.

There are reports of efficacy with other immunosuppressive drugs. If defects in the complement pathway are found, treatment with eculizumab is of benefit.

In secondary MPGN, treating the associated infection, autoimmune disease, or neoplasms is of demonstrated benefit. Patients with primary MPGN are well known to be at risk for not only a histologic recurrence in the transplanted kidney but also a clinically significant recurrence with loss of graft function

Question 247

Treatment for membranous nephropathy

Answer 247

In addition to the treatment of edema, dyslipidemia, and hypertension, inhibition of the renin-angiotensin system is recommended. Therapy with immunosuppressive drugs is also recommended for patients with primary MGN and persistent proteinuria (>3.0 g/24 h).

The choice of immunosuppressive drugs for therapy is controversial, but current recommendations are to treat with steroids and cyclophosphamide, chlorambucil, mycophenolate mofetil, or cyclosporine or rituximab, an anti-CD20 antibody directed at B cells. Attaining remission is associated with a good long-term prognosis.

Question 248

When do you test for albuminuria in px with T1DM and T2DM

Answer 248

Microalbuminuria appears 5–10 years after the onset of diabetes. It is currently recommended to test patients with type 1 disease for microalbuminuria 5 years after diagnosis of diabetes and yearly thereafter and, because the time of onset of type 2 diabetes is often unknown, to test type 2 patients at the time of diagnosis of diabetes and yearly thereafter.

Question 249

an X-linked inborn error of globotriaosylceramide metabolism secondary to deficient lysosomal α-galactosidase A (alpha-Gal A) activity, resulting in excessive intracellular storage of globotriaosylceramide. Affected organs include the vascular endothelium, heart, brain, and kidneys

Answer 249

Fabry’s dse

Renal biopsy reveals enlarged glomerular visceral epithelial cells packed with small clear vacuoles containing globotriaosylceramide; vacuoles may also be found in parietal and tubular epithelia

These vacuoles of electron-dense materials in parallel arrays (zebra bodies) are easily seen on electron microscopy. Ultimately, renal biopsies reveal FSGS. The nephropathy of Fabry’s disease typically presents in the third decade as mild to moderate proteinuria, sometimes with microscopic hematuria or nephrotic syndrome. Urinalysis may reveal oval fat bodies and birefringent glycolipid globules under polarized light (Maltese cross).

Question 250

Presentation of Alport’s syndrome

Answer 250

Classically, patients with Alport’s syndrome develop hematuria, thinning and splitting of the GBMs, and mild proteinuria (<1–2 g/24 h), which appears late in the course, followed by chronic glomerulosclerosis leading to renal failure in association with sensorineural deafness

Primary treatment is control of systemic hypertension and use of ACE inhibitors to slow renal progression. Although patients who receive renal allografts usually develop antiGBM antibodies directed toward the collagen epitopes absent in their native kidney, overt Goodpasture’s syndrome is rare and graft survival is good.

Question 251

Hypertensive nephrosclerosis is fivefold more frequent in African Americans than whites. Risk alleles associated with _____, a functional gene for apolipoprotein L1 expressed in podocytes, substantially explain the increased burden of ESRD among African Americans

Answer 251

Hypertensive nephrosclerosis is fivefold more frequent in African Americans than whites. Risk alleles associated with APOL1, a functional gene for apolipoprotein L1 expressed in podocytes, substantially explain the increased burden of ESRD among African Americans

Question 252

How does HIVAN differ from other causes of nephrotic syndrome?

Answer 252

HIV patients with FSGS typically present with nephrotic-range proteinuria and hypoalbuminemia, but unlike patients with other etiologies for nephrotic syndrome, they do not commonly have hypertension, edema, or hyperlipidemia.

atment with inhibitors of the reninangiotensin system decreases the proteinuria. Effective antiretroviral therapy benefits both the patient and the kidney and improves survival of HIV-infected patients with HIVAN and, in some cases, HIVICKassociated chronic kidney disease or ESRD. In HIV-infected patients not yet on therapy, the presence of HIVAN is an indication to initiate therapy

Question 253

Scistosoma species associated with renal dse

Answer 253

Schistosoma mansoni is most commonly associated with clinical renal disease

Question 254

PPI causes what type of AKI

Answer 254

Intrinsic –> acute tubulointerstitial nephritis

Question 255

Increased intraabdominal pressure > ___ mmHg can lead to renal vein compression and therefore decreased GFR

Answer 255

20

Abdominal compartment syndrome

Question 256

Most evident signs/symptoms in CKD 3 and 4

Answer 256

Anemia
Easy fatigability
Malnutrition

Question 257

Which of the following is TRUE regarding medication dose adjustment in CKD?
a.Maintenance doses of many drugs do not need to be adjusted in CKD
b.Loading dose of most drugs is not affected by CKD because renal elimination is not used in the calculation
c.For agents in which >20% excretion is by a nonrenal route, maintenance dose adjustment may not be needed
d.Gadolinium is the safest radiocontrast agent for patients with CKD needing immediate imaging

Answer 257

b.Loading dose of most drugs is not affected by CKD because renal elimination is not used in the calculation

Question 258

This immunosuppressive drug used after kidney transplant is a macrolide with good absorption. It blocks cytokine production, but stimulates TGF-B production. Unlike its counterpart, this drug does not produce hirsutism:
a. Azathioprine
b. Cyclosporine
c. Sirolimus
d. Tacrolimus

Answer 258

d. Tacrolimus

Question 259

A 34-year-old male with no symptoms consults for recent findings hypertension and adult polycystic kidney disease. What is a rational approach to slow down cyst growth in this patient?
a. Initiate lifetime aspirin and statin therapy
b. Rigorous BP control with Telmisartan to target lower than BP 110/75
c. Permissive BP target with Spironolactone to target of 130/80
d. Nerve blockade

Answer 259

c. Permissive BP target with Spironolactone to target of 130/80

Question 260

Which of the following causes of hyperkalemia is consistent with decreased urinary K excretion and a TTKG >8?
a.Diabetes mellitus
b.NSAID use
c.Urinary tract obstruction
d.Advanced kidney failure

Answer 260

d.Advanced kidney failure

Hyperkalemia occurs due to impaired potassium excretion or excessive potassium release from cells. The Transtubular Potassium Gradient (TTKG) helps differentiate whether the kidneys are appropriately excreting potassium.

Normally, in hyperkalemia, TTKG should be >8 (indicating appropriate renal K+ excretion).

If TTKG <5 in hyperkalemia, it suggests inadequate renal K+ excretion, often due to hypoaldosteronism or kidney dysfunction.
However, in advanced kidney failure (option d), TTKG can remain >8 even with hyperkalemia.

This occurs because the remaining functioning nephrons compensate by increasing potassium excretion, but overall kidney function is still too impaired to fully correct the hyperkalemia.

Question 261

Which of the following accounts for secondary hyperparathyroidism in CKD?
a.Increased renal secretion of phosphate
b.Negative feedback in the synthesis of PTH
c.Reduced calcitriol production
d.Hypoplasia of parathyroid gland

Answer 261

c.Reduced calcitriol production

Question 262

A 52-year old male with known chronic kidney disease stage 3 from diabetic kidney disease presents with a blood pressure of 158 to 173/92 to 103 on both office and home blood pressure monitoring. He is already on optimal doses of Amlodipine and Telmisartan. What is the next possible add-on treatment for control of his blood pressure?
a. Carvedilol 6.25 mg BID
b. Enalapril 10 mg BID
c. Diltiazem 60 mg BID
d. Hydrochlorothiazide 25 mg OD

Answer 262

a. Carvedilol 6.25 mg BID

Already on ARB and DHP CCB
HCTZ limited use in ckd 3-5

Question 263

What is the most common histology of urinary tract cancer?
a.Urothelial carcinoma
b.Squamous cell carcinoma
c.Glandular carcinoma
d.Plasmacytoid carcinoma

Answer 263

a.Urothelial carcinoma

Question 264

A 27/F is brought to the emergency department for fever. Five weeks prior, she underwent kidney transplantation and was discharged well on prednisone, tacrolimus, mycophenolate mofetil, co-trimoxazole, and isoniazid. Which of the following diagnostic tests is the LEAST helpful in determining the patient’s fever etiology?
a. Chest CT
b. Hepatitis profile
c. CMV antigenemia assay
d. Urine PCR for BK polyoma virus

Answer 264

d. Urine PCR for BK polyoma virus

Seen after >6mos

Question 265

Which of the following peritoneal fluid cell counts are diagnostic of peritoneal dialysis peritonitis?
a. WBC 50/mm3 with 75% neutrophils
b. WBC 95/mm3 with 60% neutrophils
c. WBC 105/mm3 with 55% neutrophils
d. WBC 250/mm3 with 45% neutrophils

Answer 265

c. WBC 105/mm3 with 55% neutrophils

WBC at least 100 and 50% neutros

Question 266

Detection of calcium oxalate crystals in the urinalysis of a patient with AKI is most suggestive of what clinical condition?
a.Ethylene glycol intoxication
b.Tumor lysis syndrome
c.Allograft rejection
d.Hemolytic uremic syndrome

Answer 266

a.Ethylene glycol intoxication

Question 267

According to Kidney Disease Improving Global Outcomes (KDIGO) guidelines, how much total energy intake should a patient with AKI receive?
a.15-20 kcal/kg
b.20-25 kcal/kg
c.20-30 kcal/kg
d.30-35 kcal/kg

Answer 267

c.20-30 kcal/kg

Question 268

The dipstick is a quick way to test the presence of proteinuria. However, it can be false positive in which condition?
a.Concentrated urine
b.pH <7.0
c.Excessive intake of alcohol
d.Bence-Jones protein

Answer 268

a.Concentrated urine

Question 269

Which stain is used to better identify basement membrane structure in kidney biopsies?
a.Jones methenamine silver
b.Congo red
c.Masson’s trichome
d.Hematoxylin and eosin

Answer 269

a.Jones methenamine silver

Congo red : amyloid deposits
Massons trichome: collagen deposition, assess degree of glomerulosclerosis and interstitial fibrosis
H&E: assess cllularity and architecture

Question 270

On renal biopsy, this finding is an ominous pathologic sign of irreversibility and progression to renal failure:
a. Glomerular crescents
b. Interstitial fibrosis
c. Sclerotic glomeruli
d. Synechiae formation

Answer 270

b. Interstitial fibrosis

Question 271

A 23-year-old male consulted for a 2-day history of gross hematuria. He recalls having a sore throat 3 days ago which spontaneously resolved without antibiotics. Urinalysis revealed RBC 20/hpf, with no protein, casts and crystals; hemoglobin 135 g/L, platelet count 345, C3 levels normal. What is the expected kidney biopsy finding?
a. Granular subepithelial immune complex deposition
b. Mesangial IgA deposits
c. Dense deposits of C3
d. Diffuse granular IgG, C3

Answer 271

b. Mesangial IgA deposits

IgA nephropathy since nepritic picture

Question 272

A 54 year old male who previously worked as a miner consulted for hemoptysis at the ER. Pertinent PE included nasal ulcers and decreased breath sounds on both basal lung fields. Chest radiograph showed cavitation in the left upper base and bilateral pleural effusion. Other tests revealed microscopic hematuria and albuminuria. Renal biopsy revealed pauci-immune necrotizing glomerulonephritis. What is the most likely diagnosis?
a.Granulomatosis with polyangiitis
b.Microscopic polyangiitis
c.Churg-Strauss syndrome
d.Goodpasture’s disease

Answer 272

a.Granulomatosis with polyangiitis

URT and LRT involvement + kidney involvement

Question 273

A 72 year old male with diabetes mellitus was admitted for sudden right visual field cuts and a rapid increase in baseline creatinine from a month ago. Further investigation revealed Hollenhorst plaques in the retina. Which is a proven strategy to prevent progression of disease?
a.Dialysis
b.Heparin
c.Insulin
d.Statin

Answer 273

d.Statin

Hollenhorst plaques = choleterol plaque

Question 274

Which of the following conditions is associated with the development of chronic interstitial nephritis?
a.G6PD
b.HIV
c.Neurogenic bladder
d.Vesicoureteral reflux

Answer 274

d.Vesicoureteral reflux

Question 275

Best histological correlate of renal failure in GN

Answer 275

presence of tubulointerstitial nephritis NOT the type of inciting glomerular injury

Question 276

Prognosis of MCD

Answer 276

Children: complete remission 90-95% after 8 weeks of steroid
Adult: complete remission 80-85% after 20-24 weeks of steroid therapy

Question 277

Most common autoantibody implicated in membranous nephropathy

Answer 277

70% ab against mtype phospholipase A2 (PLA2R)

Question 278

T/F intensive control of blood sugar clearly prevents progression of DM nephropathy

Answer 278

True for T1DM but not for T2DM

Question 279

What drug is associated with red green birefringent needle shaped crystals

Answer 279

Acyclovir

Question 280

What drug is associated with sheaf of wheat crystals

Answer 280

Sulfodiazine/ Sulfonamides

Question 281

Most common renal complication of lithium

Answer 281

nephrogenic DI

Question 282

Causes of papillary necrosis

Answer 282

Analgesic nephropathy
DM with UTI
Prolonged NSAID use
Sickle cell nephropathy

Question 283

Nephropathy with renal interstitial fibrosis with relative paucity of cellular infiltrates is caused by this acid

Answer 283

Artistocholic acid

AKA Chinese/Balkan nephropathy

Question 284

Triad of Lead nephropathy

Answer 284

saturnine gout, hypertension, renal insufficiency

Question 285

T/F Allopurinol and alkalinization may reverse gouty nephropathy

Answer 285

False

Question 286

What type of nephropathy due to electrolyte imbalance leads to reversible vacuolar degeneration of proximal and distal tubular cells

Answer 286

Hypokalemic nephropathy

Question 287

Formula for estimating background percentage sclerosis using age

Answer 287

(Age/2) - 10

Question 288

Dietary factors associated with lower risk of nephrolithiasis

Answer 288

Ca (dietary NOT supplement)
K
phytate

Question 289

Urologic intervention for stone with the highest likelihood of rendering the patient stone free

Answer 289

Percutaneous nephrolithostomy

Question 290

If px with struvie has recurrent giving, you might considering giving this

Answer 290

Urease inhibitor Acetohydroxamic acid

Question 291

Type of stone most common in ADPKD

Answer 291

Uric acid

more than half of stones in ADPKD are composed of uric acid

Question 292

De novo diabetes mellius after transplant is more likely caused by which immunosuppressive agent?

Answer 292

Tacrolimus

Question 293

Which of the following is true regarding the mean glomerular filtration rate (GFR)?
a.An increase in GFR is expected with aging
b.Mean GFR is lower in women than in men
c.A mild elevation in serum creatinine often signifies a substantial reduction in GFR in younger individuals
d.Relying on serum creatinine concentration is sufficient to stage chronic kidney disease (CKD)

Answer 293

b.Mean GFR is lower in women than in men

Question 294

Which of the following disorders in CKD is associated with low bone turnover with low or normal parathyroid hormone (PTH) levels?
a.Osteitis fibrosa cystica
b.Secondary hyperparathyroidism
c.Osteomalacia
d.Adynamic bone disease

Answer 294

d.Adynamic bone disease

A: high PTH
B: High PTH
C: dec Vit D

Question 295

A 45-year-old male with hypertension, dyslipidemia and chronic kidney disease (CKD) diagnosed 5 years ago consulted for chest pain. On examination, he was noted to be pale and edematous, with a BP of 170/100. Which of the following is considered a CKD-related risk factor for ischemic vascular disease?

a.Hypertension
b.Hypervolemia
c.Dyslipidemia
d.Anemia

Answer 295

d.Anemia

Non traditional risk factors
Anemia
Hyperphosphatemia
Hyperparathyroidism
Inc FGF 23
Sleep apnea
Systemic inflammation

Question 296

A 34 year old male with hypertension and CKD presents his renal ultrasound result showing a discrepancy of >1 cm in kidney length. What is your next step?
a.Perform Doppler sonography
b.Repeat imaging after 3 months
c.Start Enalapril 10 mg BID
d.Perform a kidney biopsy

Answer 296

a.Perform Doppler sonography

r/o renal artery stenosis

Question 297

Among the calcium channel blockers, which of the following may exhibit superior antiproteinuric and renoprotective effects:
a.Verapamil
b.Amlodipine
c.Nifedipine
d.Felodipine

Answer 297

a.Verapamil

NON-DHP better

Question 298

Which of the following is considered the most common opportunistic infection in renal transplant patients within the peri-transplant period (<1 month)?

a. Herpes virus
b. Legionella
c. Nocardia
d. Viral hepatitis

Answer 298

a. Herpes virus

Question 299

The progression of ADPKD has striking variability. End-stage renal disease (ESRD) typically occurs in late middle age. Risk factors include which of the following:
a.Hypertension
b.Small kidney size
c.Microscopic hematuria
d.Late diagnosis of ADPKD

Answer 299

a.Hypertension

Question 300

Which of the following DOES NOT characterize persistent or significant hematuria?

a.>3 RBCs/HPF on three urinalyses
b.Single urinalysis with >100 RBCs
c.Single positive dipstick for hematuria
d.Gross hematuria

Answer 300

c.Single positive dipstick for hematuria

Question 301

What is the dominant mechanism of metabolic acidosis in CKD?
a.Decreased ammonia production
b.Hyperkalemia
c.Decrease in HCO3 excretion
d.Hyperchloremia

Answer 301

a.Decreased ammonia production

Dec ammonia excretion –> inc retention of organic acids

Question 302

Which of the following explains the mechanism of the effectiveness of angiotensin converting enzyme inhibitors and angiotensin II receptor blockers in reducing proteinuria?
a. Decreasing K secretion
b. Improves insulin resistance
c. Maintenance of MAP <90 mmHg
d. Reducing glomerular hypertension

Answer 302

d. Reducing glomerular hypertension

Question 303

he first step in the diagnostic evaluation of hyper- or hypocalcemia is to:
a.Ensure that the alteration is not due to abnormal albumin concentrations
b.Ensure adequate hydration of the patient
c.Determine the baseline renal function
d.Rule out other electrolyte abnormalities

Answer 303

a.Ensure that the alteration is not due to abnormal albumin concentrations

Question 304

Which of the following is TRUE about or is expected of laboratory tests in the setting of uremia?
a.Slow but steady rise of serum urea and potassium levels
b.Low to normal fibrinogen and ESR
c.Elevated levels of CRP
d.High serum albumin

Answer 304

c.Elevated levels of CRP

a. rises progressively
b. inc
d. low

Question 305

Which of the following is TRUE regarding the stages of CKD?
a.Stages 1 to 3 CKD are usually asymptomatic
b.Majority of elderly patients in stage 2 or 3 CKD are stable and do not progress
c.Majority of the population would require screening for CKD stage because of the lack of symptoms
d.Clinical and laboratory complications become prominent at Stage 5 CKD

Answer 305

b.Majority of elderly patients in stage 2 or 3 CKD are stable and do not progress

Question 306

What is the cell of origin of clear cell carcinoma?
a.Proximal tubule
b.Distal tubules
c.Cortical collecting duct
d.Medullary collecting duct

Answer 306

a.Proximal tubule

Question 307

What is the standard management for stage I or II renal cell tumors?
a.Nephrectomy
b.Interferon-A adjuvant therapy
c.Chemotherapy
d.Radiotherapy

Answer 307

a.Nephrectomy

Question 308

A 27 year old female medical student spent her afternoon in a 2-hour cycling session. She felt immense pain on both thighs the following day, prompting ER consult. She related a decrease in urine output for the past 6 hrs. On urinary catheterization, dark urine was drained. Tests revealed elevated creatinine and creatine kinase. The following are mechanisms of action that contributed to her acute kidney injury EXCEPT?
a. Tubular obstruction due to heme pigment casts
b. Volume depletion resulting in renal ischemia
c. Tubular injury from free chelatable iron
d. Immune deposition resulting in glomerulonephritis

Answer 308

d. Immune deposition resulting in glomerulonephritis

Question 308

All of the following patients with recurrent UTI need further screening for urologic abnormalities EXCEPT: (Philippine CPG on the Diagnosis and Treatment of UTI in Adults. 2015 Update. Part 2. P23)
a.Persistent microscopic hematuria
b.Elevated serum creatinine
c.History of pyelonephritis
d.Multiple sexual partners

Answer 308

d.Multiple sexual partners

Question 309

Conditions that may cause false positive hydronephrosis on ultrasound

Answer 309

Diuretics
Renal cysts
Extra renal pelvis

Question 310

Conditions that may cause false negative hydronephrosis on ultrasound

Answer 310

Obstruction with volume contraction
Staghorn calculi
Retroperitoneal fibrosis
Infiltrative renal dse

Question 311

The kidneys are unlikely to recover if complete obstruction is ___ weeks duration

Answer 311

8

Question 312

A 32- year- old female is brought to the ER due to a two- week- history of progressive weakness, fatigue, increased sleeping time, nausea and headache. She was diagnosed with Papillary thyroid carcinoma a year prior and underwent total thyroidectomy and RAI but was lost to followup. Serum Na is 102mmo/L, K is 3.0mmol/L, TSH is 10.5mIU/L, and Tg is 2.1 ng/ml. What is the most likely cause of her symptoms?
A. SIADH
B. Metastatic recurrence of thyroid carcinoma to the brain
C. Hypothyroidism
D. Pituitary adenoma

Answer 312

C. Hypothyroidism

Question 313

Which of the following is part of the commonly accepted criteria for initiating maintenance dialysis in patients with chronic kidney disease:
A. Bleeding diathesis
B. Hyponatremia unresponsive to conservative measures
C. Creatinine clearance 10-14 mL/min per 1.73m2
D. Hyperphosphatemia refractory to medical therapy

Answer 313

A. Bleeding diathesis

Question 314

A 54 year old male patient diagnosed with small cell lung cancer underwent induction chemotherapy with Cisplatin + Etoposide. A few days later, he complained of decreasing urine output, tea colored-urine and rising creatinine levels. Which of the following is true about his condition?
A. Eosinophilia is present
B. FeNa <1%
C. Urinary myoglobin levels are elevated
D. Granular casts may be present

Answer 314

D. Granular casts may be present

The patient presents with acute kidney injury (AKI) after receiving Cisplatin + Etoposide for small cell lung cancer. His symptoms—decreasing urine output, tea-colored urine, and rising creatinine—suggest acute tubular necrosis (ATN), a common nephrotoxic effect of Cisplatin

Muddy brown granular casts are a hallmark finding in acute tubular necrosis (ATN), which is the most common cause of intrinsic AKI due to nephrotoxic agents like Cisplatin.

Question 315

A 54/F, diagnosed hypertensive, maintained on Amlodipine 10mg once a day, complained of progressive dyspnea on exertion and generalized body weakness. There was also associated progressive edema starting at the ankles ascending up to the knee. At the clinic, you noticed that the left leg is markedly swollen, erythematous and tender compared to the right. Her BP is 160/100, HR100, RR-25, sats-92% on room air. Her CBC showed anemia (9.5 g/dL). Urinalysis showed: amber colored, specific gravity 1.020, protein +++, RBC 2-3/hpf, WBC 0-1/hpf. What is the most likely underlying renal pathology?
A. Minimal Change Disease
B. Membranous Glomerulonephritis
C. Focal Segmental Glomerulosclerosis
D. Ligh-chain deposition disease

Answer 315

B. Membranous Glomerulonephritis

MGN = most common cause of nephrotic syndrome in elderly
Highest reported renal vein thrombosis, DVT and PE
20-30% assoc with malignancy

Question 316

A 24 year-old man presented to the emergency room with severe rightsided flank pain that radiates to the inguinal area. It was accompanied by nausea, vomiting and diaphoresis. Upon arrival at the ER, he was in distressing pain, only controlled with administration of intravenous fentanyl. A noncontrast CT scan of the KUB revealed a 0.5cm hyperdense calculi located at the distal 1/3 of the ureter. After 3 days, the patient was able to pass the calculi spontaneously. He was very concerned about recurrence of the stone, and expressed willingness for an extensive workup.
Which of the following tests in a 24-hour urine collection isrecommended for his case:
A. Total protein
B. Total glucose
C. Total bilirubin
D. Total creatinine

Answer 316

D. Total creatinine

After an episode of nephrolithiasis (kidney stones), a 24-hour urine collection is recommended to assess metabolic abnormalities and help prevent recurrence. One of the most crucial tests in the 24-hour urine collection is total creatinine, which serves as a marker of urine collection adequacy.

Additional Tests Recommended in 24-Hour Urine Collection for Nephrolithiasis:
Urinary Volume (goal: >2.5 L/day to prevent stones)
Calcium (hypercalciuria is a major risk factor for calcium oxalate/phosphate stones)
Oxalate (hyperoxaluria promotes calcium oxalate stone formation)
Citrate (a natural stone inhibitor; low levels increase risk)
Uric Acid (associated with uric acid and calcium stones)
Sodium (high sodium intake increases calcium excretion)
pH (acidic urine favors uric acid stones; alkaline urine favors calcium phosphate stones)

Question 317

Analysis of the stone revealed majority of the stone is compose of calcium oxalate. Which of the following statements is true regarding management?
A. Low calcium diet is recommended
B. A loop diuretic is recommended to substantially lower urine calcium excretion
C. Reduction of sodium intake to <2.5g/day may reduce urinary excretion of calcium
D. Sodium bicarbonate may alkalize the urine and decrease stone formation

Answer 317

C. Reduction of sodium intake to <2.5g/day may reduce urinary excretion of calcium

A: not recommended
B: thiazide
D. CaOx not affected by pH

Question 318

A 59-year-old man, hypertensive maintained on Amlodipine 10mg daily, and diagnosed with chronic hepatitis B, consults you for progressive dyspnea on exertion and generalized body weakness. You also elicited a history of progressive edema starting at the ankles ascending up to the knee since 2 weeks ago. You noticed that the left leg is markedly swollen, erythematous and tender compared to the right. BP is 160/100, HR-100, RR-25, sats-92% on room air. CBC showed anemia (9.5 g/dL). Urinalysis: amber colored, specific gravity 1.020, protein +++, RBC 20-30/hpf, WBC 0-1/hpf. If you are considering a renal disease, what is the most likely underlying renal pathology?
a. Minimal Change Disease
b. Membranous Glomerulonephritis
c. Focal Segmental Glomerulosclerosis
d. Light-chain deposition disease

Answer 318

b. Membranous Glomerulonephritis

three most common types of kidney disease resulting from HBV infection are:
●Membranous nephropathy
●Membranoproliferative glomerulonephritis (MPGN) ●Polyarteritis nodosa (PAN)

Question 319

A 64-year-old male diabetic and hypertensive, has been admitted for last five days due to fungemia and is being treated with Amphotericin B. PE findings are as follows: weight 70kg, BP 130/90 mmHg, heart rate 94 bpm, RR 24 breaths/min, Temp 36.8OC, crackles at both bases, and grade 1 bipedal edema. Urine output was 2520mL in 24 hours. CBG range is 109-110mg/dL His serum creatinine was noted to have increase from 1.2mg/dL to 2.4mg/dL, while his serum magnesium was low. What other clinical features can be expected from this type of acute kidney injury?
a. Oliguria, hypocalcemia, and non-gap metabolic acidosis
b. Oliguria, hypokalemia, and non-gap metabolic acidosis
c. Polyuria, hypocalcemia, and non-gap metabolic acidosis
d. Polyuria, hypokalemia, and non-gap metabolic acidosis

Answer 319

d. Polyuria, hypokalemia, and non-gap metabolic acidosis

DIAGNOSIS: drug induced (amphotericin B) intrinsic AKI
● Non-oliguric (polyuria), FeNa > 1%, nephrogenic DI
● Hypokalemia due to renal K wasting
● NAGMA from distal RTA (type 1)
● Na and Mg wasting

Question 320

A 28-year-old male came in due to history of hematuria. This was already his fourth episode. Urinalysis showed albumin +2, RBC 10-15/hpf. Renal biopsy was done revealing an immunofluorescent pattern of IgA. Which is correct about his case?

a. Acute renal failure and a rapidly progressive disease is expected
b. Complete remission is rare and will usually require lifetime immunosuppressive therapy
c. Monitoring of persistent proteinuria provides the greatest predictive power for adverse renal outcomes
d. There is high risk to develop ESRD within 6 months

Answer 320

Monitoring of persistent proteinuria provides the greatest predictive power for adverse renal outcomes

DIAGNOSIS: IgA nephropathy
● aka Berger’sdisease
● Most common cause of GN

a. Acute renal failure and a rapidly progressive disease is expected - slowly progressive disease over decades
b. Complete remission is rare and will usually require lifetime immunosuppressive therapy common but may still progress to ESRD over time if HTN, proteinuria not controlled
c. Monitoring of persistent proteinuria provides the greatest predictive power for adverse renal outcomes - higher proteinuria, lower eGFR and higher uric acid are independent risk factors for the development of ESRD in patients with IgA nephropathy
d. There is high risk to develop ESRD within 6 months - 50% of patients can develop ESRD within 30 yrs.

Question 321

A 36-year-old female with no known co-morbidities came to the OPD complaining of 2-week history of progressive bipedal edema which started from the ankles, now extending to mid-thighs. She claims that she has tea-colored, frothy urine and headaches. On PE, BP is 150/80, HR 87, RR 24, T 36.7C. Which laboratory test finding is consistent with the patient’s diagnosis?
a. Anemia
b. High urine protein/creatinine ratio
c. Low total cholesterol
d. Normal albumin

Answer 321

b. High urine protein/creatinine ratio

DIAGNOSIS: GN

Significant proteinuria (>500 mg/day) is a hallmark of GN.

Question 322

In which of the following cases is kidney biopsy generally contraindicated?
a. A 28-year-old APAS patient with BP of 120/80
b. A 34-year-old female SLE with hemoglobin of 9.8
c. A 57-year-old female with recurrent UTI with scarring of kidney
d. A CKD 3 patient with HBa1c 12%

Answer 322

c. A 57-year-old female with recurrent UTI with scarring of kidney

Active UTI - contraindication
Scarred kidneys = Contraindication

Question 322

A 25-year-old female came in due to fatigue and malaise. Repeated urinalysis showed albumin +++, RBC 20-30, WBC 30-40. Renal biopsy was requested revealing mesangial proliferation with lobular segmentation and tram tracking. Which management will benefit this patient?
a. ACE inhibitor
b. Cyclophosphamide
c. Dipyridamole
d. Eculizumab

Answer 322

a. ACE inhibitor

DIAGNOSIS: MPGN Type I MPGN, the most proliferative of the three types, shows mesangial proliferation with lobular segmentation on renal biopsy and mesangial interposition between the capillary basement membrane and endothelial cells, producing a double contour sometimes called tram-tracking

Question 323

An 18-year-old male developed muscle weakness and cramps of the lower extremities. BP 90/60. Serum K = 2.7meq/L, urine K = 10mmol/day. Thyroid function is normal. Serum HCO3 is 18. The hypokalemia is most likely due to:
a. Extrarenal loss of potassium
b. Gitelman’s syndrome
c. Hyperaldosteronism
d. Renal potassium wasting

Answer 323

a. Extrarenal loss of potassium

If urine K < 15= extrarenal losses

Question 324

32 year old female, previously well, consults for persistent bilateral ank pains. She has been complaining of occasional dysuria with feeling of incomplete voiding the past 2 weeks. She has no signicant past medical conditions with no maintenance medications. Vital signs are stable and physical examination reveal tenderness on both CV angles. Initial laboratory results show: Crea 1.2 mg/dl (nv 0.7-1.3) Na 140 mmol/L (nv 8.5-10.2) Albumin 41 Intact PTH 250 pg/ml (nv 15-65) Vitamin D 22 ng/mL (nv 30-50) Uric acid 7.2 mg/dl (nv 3.5-7.1) CBC Hb 130 WBC 11,500 (seg 82, lym 16) K 3.9 mmol/L Platelet ct 380,000 Ca 12 mg/dl Urinalysis: SG 1.015, pH 6.5, no glucose, trace protein, +4 blood, +2 leukocytes, +2 nitrites, 50-100 rbc/hpf, 20-50 wbc/hpf, calcium crystals many Abdominal CT scan shows nephrocalcinosis in both kidneys with bilateral nonobstructing nephrolithiasis and ureterolithiasis. Which of the following is the most appropriate step?
a. Start allopurinol 300mg/tab 1 tab 1xd
b. Start Vitamin D3 2000 iu/cap 1 cap 1xd
c. Start hydrochlorothiazide 25mg/tab 1 tab 1xd
d. Start potassium citrate 30meq 1xd

Answer 324

c. Start hydrochlorothiazide 25mg/tab 1 tab 1xd

This strongly suggests Primary Hyperparathyroidism (PHPT), the most common cause of hypercalcemia with kidney stones.

Thiazide diuretics (e.g., HCTZ) reduce calcium excretion in urine by increasing calcium reabsorption in the distal tubule.
Prevents further calcium stone formation in PHPT.
Beneficial in hypercalciuria-related nephrolithiasis.

Question 325

20 year old female with SLE complaining of “bubbly” urine. She denies dysuria, oliguria or fever. She is maintained on prednisone 5mg OD. Vital signs as follows: BP 160/90 mmHg, HR 92bpm, RR 20 cpm, Temp 37.4C with O2 99%. Systemic finding show grade 1 to 2 bipedal edema.
Labs show Crea 1.1 mg/dl (nv 0-.7-1.3)
Na 140 mmol/L K 4.1 mmol/L
CBC Hb 108 WBC 10,500 (seg 65, lym 28) Plt count 108,000
Urinalysis: cloudy, +2 protein, +4 blood, trace leukocytes, RBC >100/hpf, WBC 3- 5/hpf, many RBC casts
Kidney biopsy shows: mesangial proliferation with note of hypercellularity with expansion of mesangial matrix What is the next best step?
a. Start losartan and diuretic medications and observe
b. Increase prednisone to 60mg BID
c. Shift prednisone to high dose intravenous methylprednisolone pulse therapy
d. Start oral cyclophosphamide

Answer 325

a. Start losartan and diuretic medications and observe

Class II Lupus nephritis. No need for immunosuppresants and steroids

Question 326

Which clinical scenario warrants a kidney biopsy?
a. 20/F with gross hematuria, dysuria, frequency of 1 day duration. Urinalysis show turbid urine with 30-50 RBCs and WBCs TNTC
b. 68/F diabetic of 20 years with pedal edema, bubbly urine, and new onset hypertension. Urinalysis show +3 proteinuria, RBC 1-3/hpf and WBC 3-5/hpf
c. 35/F, previously well with episodic gross hematuria after bouts of sore throat. Urinalysis show +3 protein, RBC TNTC/hpf, WBC 3-5/hpf, many casts
d. 40/F G1P0 28 weeks AOG complaining of headache with new onset hypertension and bipedal edema. Urinalysis show +4 protein, trace blood, trace leukocytes, RBC 3/hpf, WBC 5/hpf

Answer 326

c. 35/F, previously well with episodic gross hematuria after bouts of sore throat. Urinalysis show +3 protein, RBC TNTC/hpf, WBC 3-5/hpf, many casts

A kidney biopsy is warranted when there is suspicion of an underlying glomerular disease that requires histologic diagnosis for appropriate management.

The 35-year-old female with episodic gross hematuria after sore throat and significant proteinuria, RBCs TNTC, and many casts raises suspicion for IgA Nephropathy (Berger’s Disease) or Post-Streptococcal Glomerulonephritis (PSGN). A biopsy is necessary to confirm the diagnosis and guide management.

Question 327

A 45 year old male, known type 2 diabetes mellitus for 5 years, is noted to have consistent microalbuminuria for the last 3 medical consultations. Which of the following is he MOST at risk for?
a. Cardiovascular complications
b. End stage renal disease
c. Hepato-renal syndrome
d. Complicated urinary tract infections

Answer 327

a. Cardiovascular complications

Question 328

A 24 year old male residing in Payatas Quezon City complains of acute hemoptysis over the past week. He has been previously well with no drug history. He is a 3 pack year smoker. He also lives with his father who is taking anti-koch’s medication via DOTS for the past 2 months. Vital signs: BP 120/80 HR 72bpm, RR 26 cpm, temp 38.5C with O2 93%. Urinalysis shows +4 blood with rbc TNTC and many red blood cell casts. Which of the following is the most likely etiology?
a. Acute disseminated tuberculosis
b. Renal cell carcinoma with lung metastasis
c. Goodpasture disease
d. IgA nephropathy

Answer 328

c. Goodpasture disease

Goodpasture since with hemoptysis and kidney involvement

Question 329

A 20 year old male college student consults for decreasing urine output, tea- colored urine and bipedal edema. He denies any previous medical condition except for impetigo 3 weeks ago. On PE, BP 160/90, HR 114bpm, RR 26 cpm, with note of periorbital and bipedal edema and scabs on all extremities. What is the classic nding expected in his urinalysis?
a. Muddy brown casts
b. Hyaline casts
c. Nephrotic range proteinuria
d. Red blood cell casts

Answer 329

d. Red blood cell casts

Dx: PSGN –> nephritic syndrome

a. Muddy brown casts —> ATN
b. Hyaline casts are non-specific and can be found in normal individuals, dehydration, or mild kidney disease.
C. Nephrotic range proteinuria is rare

Question 329

A 25-year-old woman, previously healthy, is admitted for severe body weakness. She has been having diarrhea and vomiting for the last two days. On admission, vital signs taken are as follows: Temp = 37.1C, BP=80/60, HR=110bpm, RR=22/min. She has faint pulses and poor skin turgor. Her serum creatinine was 2.4mg/dL. Which of the following is most diagnostic of the underlying renal injury?
a. BUN/Creatinine ratio less than 20
b. Fractional excretion of sodium less than 1%
c. Urine Osmolality less than 500 mOsm/kg
d. Repeat serum creatinine after adequate hydration and with normal BP

Answer 329

d. Repeat serum creatinine after adequate hydration and with normal BP

Response to restoration of hemodynamics = diagnostic of pre renal

Question 330

A 55-year-old woman was admitted for severe community-acquired pneumonia. After initial blood draw, she was started on Cefepime + Amikacin. Her baseline serum creatinine was 0.6mg/dL. Over the next 5 days, she was normotensive with resolution of fever. Urine output was sustained at around 1.5 to 2 liters per day. Repeat serum creatinine on her 5th hospital day was noted to be increased at 3.2mg/dL. What is a common finding given the likely diagnosis of azotemia?
a. Low FeNa
b. Hypomagnesemia
c. Hypocalcemia
d. Nongap metabolic acidosis

Answer 330

b. Hypomagnesemia

Aminoglycosides can cause renal magnesium wasting, leading to hypomagnesemia.

Question 331

A 55-year-old man, admitted for shortness of breath, has a large mediastinal mass on chest Xray. A Chest CT scan with IV contrast was done. 3 days later, a routine blood examination showed a serum creatinine of 2.6 mg/dL. His serum creatinine on admission was 1.1 mg/dL. He has good urine output with normal vital signs during his connement. Which of the following likely contributes to the mechanism of the patient’s acute azotemia?
a. Thrombotic microangiopathy
b. Efferent arteriolar vasodilation due to loss of Angiotensin II activity
c. Afferent renal vasoconstriction due to prostaglandin depletion
d. Small vessel occlusion causing hypoxia in the renal outer medulla

Answer 331

d. Small vessel occlusion causing hypoxia in the renal outer medulla

Contrast-induced nephropathy (CIN) is caused by renal medullary hypoxia due to small vessel occlusion.
Mechanism:
Renal vasoconstriction → Contrast agents cause endothelial dysfunction, leading to reduced nitric oxide and increased endothelin, resulting in medullary ischemia.
Direct tubular toxicity → Contrast media damages tubular cells, increasing oxidative stress.
Ischemia of the renal outer medulla → The medulla is highly vulnerable to hypoxia, as it already functions in a low-oxygen environment.

Question 332

Among patients receiving aggressive uid resuscitation for extensive uid losses, a decrease in renal output with rise in serum creatinine may indicate which complication of management?
a. Renal vein compression
b. Acute pulmonary congestion
c. Loss of counterregulatory mechanisms
d. Acute tubular injury

Answer 332

a. Renal vein compression

Question 333

A 58-year-old man, with known diabetes and hypertension has the following laboratory results:
ABG: pH=7.30, pCO2=30 mmHg, HCO3=15 mmol/L
Serum Na = 136 mmol/L
Serum K =5.8 mEq/L
Serum Cl=115 mEq/L
Blood glucose = 128mg/dL Serum creatinine: 1.4mg/dL
These laboratory ndings are consistent with which of thefollowing?
a. Hyporeninemic hypoaldosteronism
b. Hypertensive nephrosclerosis
c. Proximal renal tubular acidosis
d. Distal renal tubular acidosis

Answer 333

a. Hyporeninemic hypoaldosteronism

C and D should have low K. Only Type 4 RTA has high K

Question 334

A 35-year-old male was stabbed multiple times by an
unknown assailant and was brought to the emergency
department. On assessment, he was actively hemorrhaging, lethargic, with the following vital signs: BP 70/50 mmHg, HR 120 bpm, RR 12 cpm. He had a feeble pulse and peripheral cyanosis.
Which is a true statement on this case?
a. The osmotic threshold for AVP release is reduced.
b. The slope of the AVP response curve to osmolality is
decreased.
c. There is a reduction in the sensitivity of circulating AVP levels
to osmolality.
d. Serum Na+ is the sole determinant of AVP levels

Answer 334

a. The osmotic threshold for AVP release is reduced.

Question 335

A 70-year-old male was brought to the ED due to changes insensorium. Work-up revealed: serum Na+ 118 mEq/L, BUN 65 mg/dL, random blood sugar 108 mg/dL. What is the computed serum osmolality?
a. 235 mOsm/kg H2O
b. 245 mOsm/kg H2O
c. 255 mOsm/kg H2O
d. 265 mOsm/kg H2O

Answer 335

d. 265 mOsm/kg H2O

2 Na + (BUN /2.8 )+ gluc/18

Question 336

A 35 y/o HIV patient developed weakness and hypotension after stopping ketoconazole therapy for a fungal infection. Serum potassium was 6.4 mmol/l. What are the expected TTKG pre and
post fludrocortisone challenge?
a. TTKG <5 presteroid and > 8 post steroid
b. TTKG < 5 presteroid and < 8 post steroid
c. TTKG > 8 presteroid and no change post steroid
d. TTKG > 8 presteroid and < 8 post steroid

Answer 336

a. TTKG <5 presteroid and > 8 post steroid

Adrenal Insufficiency (Likely Primary Adrenal Insufficiency due to Ketoconazole Withdrawal in an HIV Patient)

This 35-year-old HIV patient developed weakness, hypotension, and hyperkalemia (K+ = 6.4 mmol/L) after stopping ketoconazole therapy.

Ketoconazole is a potent inhibitor of adrenal steroidogenesis, particularly cortisol and aldosterone synthesis.

Question 337

What is the Corrected Anion Gap of this patient with the following labs?
Na: 150, Cl: 113, HCO3 11, Serum albumin: 2.5 g/dl ( nv of 4.5g/dl)
a. 21 b. 26 c. 31 d. 34

Answer 337

c. 31

AG = 150 - (113+11) = 26

corrected anion gap = AG + 2.5 x (4.5-2.5) –> 31

Question 337

What is the mechanism of Vancomycin in causing acute
kidney injury?
a. Tubular membrane pore formation
b. Direct tubular injury by reactive oxygen species
c. Intratubular obstruction
d. Interstitial inflammation

Answer 337

c. Intratubular obstruction

Several antimicrobial agents are commonly associated with AKI. Vancomycin may be associated with AKI from tubular injury, particularly when trough levels are high and when used in combination with other nephrotoxic antibiotics. Vancomycin can also crystalize in tubules and cause intratubular obstruction

Question 338

What is a reliable sign of hypovolemia in an adult patient?
a. Increased jugular venous pressure
b. 20 mmHg systolic blood pressure drop on sitting up
c. 30 bpm increase in HR on standing up
d. Dry oral mucosa

Answer 338

c. 30 bpm increase in HR on standing up

HYPOVOLEMIA
On examination, diminished skin turgor and dry oral mucous membranes are less than ideal markers of a decreased ECFV in adult patients; more reliable signs of hypovolemia include:
● a decreased jugular venous pressure (JVP)
● Orthostatic tachycardia (an increase of >15–20 beats/min upon standing)
● orthostatic hypotension (a >10–20 mmHg drop in blood pressure on standing)

Question 338

In a patient with milk alkali syndrome, what is the likely mechanism for metabolic alkalosis?
a. Increase bicarbonate load
b. Gastrointestinal bicarbonate loss
c. Renal bicarbonate loss
d. Decrease hydrogen absorption

Answer 338

a. Increase bicarbonate load

Question 339

JR, 77 years old male is being treated for hyponatremia
from chronic diuretic use. Baseline serum Na was 107 mEqs/L.After 6hrs of correction with PNSS, serum Na was 128 mEqs/L. After 24 hrs, he developed diplopia and dysarthria that progressed to loss of consciousness. What is the possible
explanation of this condition?
a. Immune mediators entering the blood brain barrier
b. Thrombosis in middle cerebral artery
c. Hemorrhage in the pons and medulla
d. Apoptosis of neurons in the cerebellum

Answer 339

a. Immune mediators entering the blood brain barrier

Brain cells accommodate to a chronic increase in ECF osmolality (>48 h) by activating membrane transporters that mediate influx and intracellular accumulation of organic osmolytes (creatine, betaine, glutamate, myoinositol, and taurine); this results in an increase in ICF water and normalization of brain parenchymal volume

Question 340

What is the mechanism of hypokalemia in magnesium deficiency?
a. Excitatory activity on muscle Na K ATPase
b. Increase in ENaC activity
c. Intracellular block of K efflux through the secretory K channel
d. Apoptosis of ROMK containing cells

Answer 340

c. Intracellular block of K efflux through the secretory K channel

Question 340

HR, a 28-year-old female, presented with a 1-month history of progressive oedema. On examination, she was seen to have elevated blood pressure, distended abdomen with positive fluid wave on palpation, and grade 2 bipedal pitting oedema. Renal biopsy revealed focal and segmental scarring, most prominent in the glomeruli obtained from the corticomedullary junction. Increased incidence of this condition is most commonly associated with podocytic polymorphisms of which gene?
a. APOL1
b. NPHS1
c. NPHS2
d. TRPC6

Answer 340

a. APOL1

Question 341

. TS, a 58-year-old diabetic male who has been on oral hypoglycemics for at least 8 years, consulted for a 4-month history of persistent bipedal oedema. Physical examination revealed normal blood pressure, but with periorbital and grade 2 bipedal pitting oedema. Diagnostic tests revealed a serum creatinine level of 2.9 mg/dL, and a spot urine albumin/creatinine ratio of 1442.8 mg/g. Which of the following statements regarding urine assays for proteinuria is accurate?
a. Dipstick evaluation detects the most acidic proteins, including those with a higher isoelectric point, such as albumin.
b. Microalbuminuria can be detected by a urinary dipstick protein analysis.
c. The ratio of total protein concentration to creatinine concentration is specific to albumin excretion, and excludes light-chain proteins.
d. Urine albumin or total protein should be normalized to urine creatinine concentration in order to discount the effects of urinary dilution or concentration.

Answer 341

d. Urine albumin or total protein should be normalized to urine creatinine concentration in order to discount the effects of urinary dilution or concentration.

A. Dipstick evaluation detects ONLY ALBUMIN, and gives FALSE-POSITIVE results at pH >7.0
B. Microalbuminuria IS BENEATH DETECTION by a urinary dipstick protein analysis.
C. The ratio of total protein concentration to creatinine concentration is NOT specific to albumin excretion, and MAY INDICATE light-chain proteins

Question 342

MC, a 51-year-old female, consulted for severe right flank pain, radiating to the right labial area. This was accompanied by gross hematuria. A presumptive diagnosis of urolithiasis was made. Based on the initial presentation, and epidemiologic data, an imaging study would most likely show a stone lodged in which area?
a. Distal ureter
b. Proximal ureter
c. Renal pelvis
d. Urinary bladder

Answer 342

a. Distal ureter

Question 342

BG, a 41-year-old male, was recently admitted for azotemia, proteinuria, and hematuria. History was unremarkable, apart from a recent travel to a malaria-endemic area. A kidney biopsy was done, consistent with mesangioproliferative glomerulonephritis. This finding is most consistent with:
a. Plasmodium falciparum malaria
b. Plasmodium malariae malaria
c. Plasmodium ovale malaria
d. Plasmodium vivax malaria

Answer 342

a. Plasmodium falciparum malaria

Question 343

SG, a 27-year-old male, consulted for left flank pain, nausea and vomiting, low-grade fever with chills, and gross hematuria. Physical examination revealed some signs of dehydration, with direct tenderness over the left lower back. Diagnostic examination showed gross and microscopic pyuria, along with leukocytosis and neutrophilia. A non-obstructing stone, with a widest diameter of 0.9 cm, was seen in the left renal pelvis on sonogram. Which of the following suggests an indication for urologic intervention?
a. Concurrent urinary tract infection
b. Flank pain and tenderness
c. Nausea and vomiting, with dehydration
d. Renal stone > 0.5 cm in size

Answer 343

a. Concurrent urinary tract infection

Question 343

RB, a 50-year-old male patient with chronic tophaceous gout, consulted for sonogram findings of non-obstructing bilateral nephrolithiases. He has been experiencing tolerable lower back pains, associated with position and movement. His urinalysis showed a pH of 5.0. What is the best initial pharmacologic management in this case?
a. Potassium citrate
b. Prophylactic antibiotics
c. Sambong supplementation
d. Tiopronin

Answer 343

a. Potassium citrate

Question 344

JF, a 67-year old male, has been on heart failure medications for ischemic cardiomyopathy. On his latest series of consultations, the cardiologist noted progressive increase in his serum creatinine levels, translating into a steady decline in renal function. Which of the following statements is accurate regarding his condition?
a. Decreased intraabdominal pressure and abdominal congestion correlate with renal dysfunction.
b. Neurohormonal activation and release of arginine vasopressin has the most impact in reduced eGFR in cardiorenal syndrome.
c. Systemic venous congestion with decreased backward pressure plays a crucial role in cardiorenal syndrome
d. This is a consequence of reduced cardiac output in heart failure.

Answer 344

c. Systemic venous congestion with decreased backward pressure plays a crucial role in cardiorenal syndrome

Question 345

GB, a 52-year-old diabetic male, was rushed into the ER
for progressive angina for more than 24 hours,
unrelieved by rest and nitrates. Review of history
showed previously normal renal indices on his clinic
visit less than a month ago. Initial PE showed an obese
male with an actual body weight of 110 kg, diaphoretic,
with cold, clammy hands, hypotension, and tachycardia.
Baseline laboratory tests in the ER revealed azotemia
and markedly high urine specific gravity. The first 4
hours were marked by a urine output of less than 30
cc/hour. Which of the following is a microvascular event
that might have contributed to his renal condition at
initial presentation?
A. Diminished leukocyte endothelial adhesion.
B. Enhanced vasodilation in response to nitric oxide.
C. Impaired arteriolar vasodilation in response to
Angiotensin I.
D. Significant endothelial and vascular smooth muscle
cellular damage

Answer 345

D. Significant endothelial and vascular smooth muscle
cellular damage

Question 346

In relation to the preceding case, which of the following
compensatory mechanisms is/are responsible for
maintaining normal glomerular filtration in the early
phase of renal injury?
A. Arteriolar dilatation resulting from myogenic reflex in the setting of low perfusion pressure.
B. Capillary endothelial hypertrophy secondary to release
to tissue growth factors.
C. Nitric oxide-mediated increase in intraglomerular
pressure via afferent arteriolar dilatation.
D. Reflex afferent arteriolar constriction and efferent
arteriolar dilatation

Answer 346

A. Arteriolar dilatation resulting from myogenic reflex in thesetting of low perfusion pressure.

Normal GFR is maintained in part by renal blood flow and the relative resistances of the afferent and efferent renal arterioles, which determine the glomerular plasma flow rate and the transcapillary hydraulic pressure gradient that drive glomerular ultrafiltration.

Mild degrees of hypovolemia and reductions in cardiac output elicit compensatory renal physiologic changes…. Mediators of this response include angiotensin II, norepinephrine, and vasopressin (also termed antidiuretic hormone). Glomerular filtration can be maintained despite reduced renal blood flow by angiotensin II–mediated renal efferent vasoconstriction, which maintains glomerular capillary hydrostatic pressure closer to normal and thereby prevents marked reductions in GFR if renal blood flow reduction is not excessive.

In addition, a myogenic reflex within the afferent arteriole leads to dilation in the setting of low perfusion pressure, thereby maintaining glomerular perfusion. Intrarenal biosynthesis of vasodilator prostaglandins (prostacyclin, prostaglandin E2), kallikrein and kinins, and possibly nitric oxide (NO) also increases in response to low renal perfusion pressure.

Question 347

Which of the following patient and intervention
variables would play an important role in the risk
stratification for contrast- induced acute kidney injury
A. Albumin level prior to procedure
B. Blood urea nitrogen level
C. Hematocrit
D. Type of contrast agent

Answer 347

C. Hematocrit

Question 348

which of the following nutritional recommendations has the most robust clinical evidence, and may therefore be advised to your aforementioned patient with CKD?
A. Adopt a healthy and diverse diet, with equal consumption of plant- and animal-based proteins.
B. Maintain a protein-intake of 0.8 g/kg body weight/day.
C. Sodium intake should be restricted to < 2 g of sodium chloride per day.
D. Strict adherence to a very low protein diet supplemented by ketoacid analogs of branched chain amino acids.

Answer 348

B. Maintain a protein-intake of 0.8 g/kg body weight/day.

The ADA suggests a protein intake of 0.8 mg/kg of body weight/day in individuals with diabetic kidney disease. Compared with higher levels of dietary protein intake, this level slowed GFR decline with evidence of a greater effect over time. Higher levels of dietary protein intake (>20% of daily calories from protein or >1.3 g/kg/day) have been associated with increased albuminuria, more rapid kidney function loss, and CVD mortality and therefore should be avoided.

Question 349

BR, a 66-year-old male diabetic diagnosed with CKD checks in at the clinic for a routine follow-up. He reports no symptoms, but presents laboratory results as follows: eGFR of 22 ml/min/1.73 m2 (CKD-EPI 2021), HbA1c of 8%, arterial blood pH of 7.33, with a bicarbonate of 19 mmol/L, and serum potassium of 5.5 mmol/L. Which of the following is the most appropriate initial management to address the metabolic acidosis?
A. Advise a protein-restricted diet to reduce acid burden.
B. Discontinue his on-board potassium- sparing diuretic.
C. Initiate oral sodium bicarbonate supplementation.
D. Start insulin therapy

Answer 349

B. Discontinue his on-board potassium- sparing diuretic.

Metabolic acidosis is a common disturbance in CKD. The majority of patients can still acidify the urine, but they produce less ammonia and, therefore, cannot excrete the quantity of protons required to maintain acid-base balance in most diets. Hyperkalemia, if present, further depresses ammonia production. In most patients, the metabolic acidosis is mild; the pH is rarely <7.32 and can usually be corrected with oral sodium bicarbonate supplementation.

Question 350

Secondary hyperparathyroidism secondary to chronic kidney disease is best addressed by:
A. Avoidance of lanthanum to prevent calcium deposits in the vascular endothelium
B. Dietary calcium restriction and reasonable phosphate intake
C. Low dietary phosphate intake and use of sevelamer
D. Surgical resection of the parathyroid glands

Answer 350

C. Low dietary phosphate intake and use of sevelamer

Secondary hyperparathyroidism (SHPT) in chronic kidney disease (CKD) occurs due to elevated phosphate levels, decreased calcium, and low calcitriol (active vitamin D).

Phosphate retention stimulates parathyroid hormone (PTH) secretion, worsening bone disease and vascular calcifications.
Managing SHPT in CKD involves controlling phosphorus levels to reduce PTH stimulation.

The optimal management of secondary hyperparathyroidism and osteitis fibrosa is prevention. Once the parathyroid gland mass is very large, it is difficult to control the disease. Careful attention should be paid to the plasma phosphate concentration in CKD patients, who should be counseled on a low-phosphate diet as well as the appropriate use of phosphate-binding agents, which are taken with meals and complex dietary phosphate to limit its GI absorption. Examples of phosphate binders are calcium acetate and calcium carbonate. A major side effect of calcium-based phosphate binders is calcium accumulation and hypercalcemia, especially in patients with low-turnover bone disease. Sevelamer and lanthanum are non-calcium-containing polymers that also function as phosphate binders; they do not predispose CKD patients to hypercalcemia and may attenuate calcium deposition in the vascular bed. Tenapanor is a sodium-proton inhibitor that decreases GI phosphate absorption & may be useful to manage hyperphosphatemia in CKD & dialysis patients.

Question 351

CC, a 33-year-old male, was brought in for evaluation as a living kidney donor for a CKD patient. Which of the following clinical information constitutes an absolutely high risk for this patient to develop post-donation kidney disease and possible ESKD?
A. CC has an aunt on insulin for type 1 diabetes mellitus
B. CC was previously treated for minimal change disease when he was 8 years old.
C. During pre-employment evaluation 2 years ago, CC had a one-time BP measurement of 130/70 mmHg.
D. Further investigation revealed CC was adopted, and therefore has no recollection of significant blood-related familial illnesses.

Answer 351

B. CC was previously treated for minimal change disease when he was 8 years old.

A potential living kidney donor must have minimal risk for future kidney disease. Any condition predisposing the donor to CKD or ESKD is an absolute contraindication to donation.

Question 352

“Maria dela Cruz”, a vagrant with no reliable informant
or medical alert bracelet, was brought into the acute
care unit after being witnessed to be in an apparent
tonic-clonic seizure by roving security personnel at the
Luneta Park. Initial evaluation revealed an unconscious
female with no other significant physical findings.
Baseline laboratory results revealed normal renal
indices, but with a serum sodium level of 103 mmol/L.
Which of the following are appropriate diagnostic
interventions for initial investigation?
A. Arterial blood gas, cranial computed tomography, serum
vasopressin
B. Serum glucose, thyroid function test, urine osmolality
C. Urine specific gravity, urinary fractional sodium
excretion
D. 12-lead electrocardiogram, urine glucose, serum
sodium

Answer 352

B. Serum glucose, thyroid function test, urine osmolality

Serum glucose should also be measured; plasma Na+ concentration falls by ~1.6–2.4 mM for every 100-mg/dL increase in glucose, due to glucose-induced water efflux from cells; this “true” hyponatremia resolves after correction of hyperglycemia. In the appropriate clinical setting, thyroid, adrenal, and pituitary function should also be tested; hypothyroidism and secondary adrenal failure due to pituitary insufficiency are important causes of euvolemic hyponatremia, whereas primary adrenal failure causes hypovolemic hyponatremia. Urine electrolytes and osmolality are crucial tests in the initial evaluation of hyponatremia.

A urine Na+ concentration <20–30 mM is consistent with hypovolemic hyponatremia, in the clinical absence of a hypervolemic, Na+-avid syndrome such as CHF (Fig. 53-5). In contrast, patients with SIAD will typically excrete urine with an Na+ concentration that is >30 mM. However, there can be substantial overlap in urine Na+ concentration values in patients with SIAD and hypovolemic hyponatremia, particularly in the elderly; the ultimate “gold standard” for the diagnosis of hypovolemic hyponatremia is the demonstration that plasma Na+ concentration corrects after hydration with normal saline.

Question 353

Hypomagnesemia induces hypokalemia by which of the following mechanisms?
A. Inhibition of muscle Na+/K+-ATPase activity reduces influx into the myocytes, and secondary kaliuresis.
B. Magnesium depletion reduces potassium reabsorption in the distal nephron
C. Potassium and magnesium are selectively secreted in the proximal nephron.
D. Many disorders of the proximal nephron cause both potassium and magnesium wasting through co-transport mechanisms.

Answer 353

A. Inhibition of muscle Na+/K+-ATPase activity reduces influx into the myocytes, and secondary kaliuresis.

Magnesium depletion has inhibitory effects on muscle Na+/K+-ATPase activity, reducing influx into muscle cells and causing a secondary kaliuresis. In addition, magnesium depletion causes exaggerated K+ secretion by the distal nephron; this effect is attributed to a reduction in the magnesium dependent, intracellular block of K+ efflux through the secretory K+ channel of principal cells

Question 354

Which of the following statements is ACCURATE regarding treatment of hyperkalemia?
A. Calcium reduces the action potential threshold, thereby causing immediate antagonism of the cardiac effects of hyperkalemia.
B. Insulin causes a gradual but sustained reduction in serum potassium concentration by shifting potassium into the cells.
C. Intravenous bicarbonate plays a significant role in the acute treatment of hyperkalemia, and attenuates hyperkalemia by sustained intravenous infusion.
D. Salbutamol and insulin with glucose have an additive potassium-lowering effect

Answer 354

D. Salbutamol and insulin with glucose have an additive potassium-lowering effect

Insulin lowers plasma K+ concentration by shifting K+ into cells. The recommended dose is 10 units of intravenous regular insulin followed immediately by 50 mL of 50% dextrose (D50W, 25 g of glucose total); the effect begins in 10–20 min, peaks at 30–60 min, and lasts for 4–6 h. Bolus D50W without insulin is never appropriate, given the risk of acutely worsening hyperkalemia due to the osmotic effect of hypertonic glucose. β2-Agonists, most commonly albuterol, are effective but underused agents for the acute management of hyperkalemia. Albuterol and insulin with glucose have an additive effect on plasma K+ concentration; however, ~20% of patients with ESRD are resistant to the effect of β2-agonists; hence, these drugs should not be used without insulin. The recommended dose for inhaled albuterol is 10–20 mg of nebulized albuterol in 4 mL of normal saline, inhaled over 10 min; the effect starts at about 30 min, reaches its peak at about 90 min, and lasts for 2–6 h. Hyperglycemia is a side effect, along with tachycardia. Β2- Agonists should be used with caution in hyperkalemic patients with known cardiac disease.

Question 355

What is a unique characteristic feature in a patient’s
kidney biopsy whose HbA1c levels range from 10 to
12% over the last 15 years due to glomerulosclerosis of
nodules?
A. Mesangial necrosis and hemorrhage
B. Uniform thickening of the tubular membrane
C. Effacement of the foot processes
D. Eosinophilic PAS positive lesion

Answer 355

D. Eosinophilic PAS positive lesion

Question 356

A 38-year-old male consulted your clinic 10 years ago for unexplained gross hematuria and proteinuria. His pertinent laboratory at that time were serum creatinine 201 umol/L, HBA1c 5.2, KUB ultrasound with normal appearing kidneys, ureter and bladder and no lithiasis noted. You advised him for biopsy but he was lost to follow up. He came again for consult at your clinic today complaining of generalized weakness, deafness and blurring of vision. His latest serum Creatinine is 408 umol/L. What is the likely underlying cause of his clinical condition?
A. Mutation in α5(IV) collagen chain on chromosome X
B. Autosomal dominant disorder in COL(IV) α3 locus
C. Haploinsufficiency for the transcription factor LMX1B
D. Risk allele associated with APOL1 gene

Answer 356

A. Mutation in α5(IV) collagen chain on chromosome X

Question 357

What is the best therapy for Hepatorenal Syndrome?
A. Albumin infusion
B. Terlipressin
C. Midodrine with octreotide
D. Transplant

Answer 357

D. Transplant

Question 358

A medical clerk asks you on the basic concepts of a
patient with known heart failure that is now presenting
with progressive renal dysfunction. The clerk asks you
regarding the mechanism behind the possible
cardiorenal syndrome. What will you tell the clerk?
A. Diuretics can further increase the serum creatinine inthe background of elevated right-sided filling pressure
B. The condition has a low mortality as long as the patientis adequately dialyzed
C. It is usually exacerbated by a “forward failure” resulting from decreased intraabdominal pressure
D. In late stages with low cardiac output state,
noradrenalin will absolutely not improve renal function
in selected individuals

Answer 358

A. Diuretics can further increase the serum creatinine inthe background of elevated right-sided filling pressure

Question 359

A 43 year old male patient came to you for further
workup and management of calcium oxalate crystals in
his urinalysis. To objectively give a sound therapeutic
recommendation, how will you instruct your patient in
collecting urine samples for your baseline assessment?
A. Collect one early morning, clean catch urine sample
without fasting
B. Collect two 24 hrs urine sample with usual diet
C. Collect two 24 hrs urine sample on a weekend with fluid
restriction
D. Collect a random urine sample in the middle of the day
and drink at least 2L of water 2 hrs prior

Answer 359

B. Collect two 24 hrs urine sample with usual diet

Question 360

A 62 year old male complains of 3 months of recurrent flank pain and hematuria. He also mentioned increased thirst and frequent urination, which he attributes to drinking more fluids to alleviate his symptoms. He has been feeling fatigued and has experienced some weight loss over the past few months. Pertinent laboratory tests include serum calcium: 11.5 mg/dL (normal range: 8.5-10.5 mg/dL), Parathyroid hormone (PTH): 120pg/mL (normal range: 10-65pg/mL); Creatinine: 1.0mg/dL (normal range: 0.6-1.2mg/dL). What is a likely finding in the urinalysis?
A. Calcium phosphate
B. Calcium oxalate
C. Uric acid
D. Struvite

Answer 360

A. Calcium phosphate