NEPHRO Flashcards
Site of erythropoietin (EPO) production
Interstitial cells of the peritubular capillaries
ADH actions on V1 vs V2 receptors
part of nephron that:
* Absorb Na* and H20 and secrete K* VS
* Absorb K* and secrete H*
main trigger in ADH secretion
differentiate ascending vs descending limb of loop of Henle in terms of permeability to solute and water
diuretics that can cause metabolic acidosis (1)
diuretics that can cause metabolic alkalosis (2)
Test for measurement of albuminuria
Urinary albumin to creatinine ratio
Most useful renal imaging study
Renal ultrasound
Renal biopsy is not advised in a patient with bilaterally small kidneys because of 3 reasons
- It is technically difficult and has a greater likelihood of causing bleeding and other adverse consequences
- There is usually so much scarring that the underlying disease may not be apparent,
- The window of opportunity to render disease-specific therapy has passed.
Imaging test for diagnosis of nephrolithiasis
Helical computed tomography (CT) scanning without radiocontrast enhancement
Most common form of renal replacement therapy for AKI
Hemodialysis
Malnutrition is an indication for initiation of renal replacement therapy in patients with CKD
True or False
True
Number of hours of hemodialysis in majority of ESRD patients
9-12hrs each weed
divided into 3 equal sessions
Educational programs should be commenced at what stage of CKD
No later than stage 4 CKD
Most common therapeutic modality for end-stage renal disease (ESRD)
Hemodialysis
Leading cause of ESRD
Diabetes mellitus
Dialysis access with highest long-term patency rate
Fistula
Most important complication of arteriovenous grafts
Thrombosis of the graft and graft failure
Most common acute complication ofhemodialysis, particularly among DM patients
Hypotension
Most common additives to peritoneal dialysis solutions (3)
- Heparin
- Antibiotics
- Insulin
Most common organisms in PD-related peritonitis
Gram-positive cocci, including Staphylococcus (reflecting the origin from the skin)
Absolute indication for the urgent initiation of or intensification of dialysis prescription
Uremic pericarditis
Definition of AKI
- A rise of creatinine of at least 0.3 mg/dL within 48 h or
- Rise of creatinine 50% higher than baseline within 1 week; or
- reduction in urine output to < 0.5 mL/kg/h for >6 hours
Definition of oliguria
<400 mL/24 h
Hallmark of AKI
elevated BUN
Light chain cast nephropathy is associated with what disease
multiple myeloma
Most common form of AKI
Prerenal Azotemia
Renal autoregulation usually fails once the systolic blood pressure falls below…
80mmHg
Type of ATN with Extensive necrosis, PCT and DT affected, relatively longer lengths of tubules
Toxic-type ATN [e.g. in use of aminoglycosides, radiocontrast dyes)
Most common clinical course of contrast nephropathy
- A rise in SCr beginning 24-48h following exposure
- Peak within 3-5 days
- Resolution within 1 week
Most common protein in urine and produced in the thick ascending limb of the loop of Henle
Uromodulin/Tamm-Horsfall Protein
In the absence of a clinical diagnosis, the only recourse to establish an etiology in early-stagee CKD is
Kidney biopsy
Definitive treatment of the hepatorenal syndrome
liver transplantation
Continuous Renal Replacement Therapy is often preferred in patients with these 3 conditions ….
- Severe hemodynamic instability
- Cerebral edema
- Significant volume overload
GFR of stage 5 CKD…
GFR <15%
In early nephropathy, such as in diabetic nephropathy, microalbuminuria occurs… quanrtity of proteinuria in microalbuminuria ….. ____ mg/24 h
30-300mg/ day
Major side effect of calcium-based phosphate binders
hypercalcemia
Leading cause of morbidity and mortality in patients at every stage of CKD
cardiovascular disease
Stage of CKD where normocytic, normochromic anemia appears
- As early as Stage 3 CKD
- Almost universal by Stage 4 CKD
Primary cause of anemia in CKD
Insufficient production of EPO by the diseased kidneys
Target hemoglobin concentration in CKD
100-115 g/L
Stage of CKDwhere peripheral neuropathy usually becomes clinically evident
Stage 4 CKD
Protein excretion >____mg is an indication for therapy with ACEi/ARBs in CKD
> 300mg
mechanism behind Uremic fetor
Derives from the breakdown of urea to ammonia in saliva and is often associated with an unpleasant metallic taste (dysgeusia)
Most important initial diagnostic step in the evaluation of a patient presenting with elevated serum creatinine
To distinguish newly diagnosed CKD from acute or subacute renal failure
Classic lesion of secondary hyperparathyroidism; high bone turnover with increased PTH levels
Osteitis fibrosa cystica
Low bone turnover with low or normal PTH levels
Adynamic bone disease
Devastating condition seen almost exclusively in patients with advanced CKD
Calciphylaxis
Seen in patients with CKD who have been exposed to gadolinium
Nephrogenic fibrosing dermopathy
type of cast seen in glomerulonephritis
RBC casts or dysmorphic RBCs seen in the sediment
Most common causes (2) of glomerulonephritis throughout the world (save for subacute bacterial endocarditis in the Western hemisnhere)
Malaria and schistosomiasis
Prototypical for acute endocapillary proliferative GN
Poststreptococcal GN (PSGN)
PSGN due to impetigo develops ____weeks after skin infection and ____weeks after streptococcal pharyngitis
PSGN due to impetigo
* develops 2-6 weeks after skin infection
* and 1-3 weeks after streptococcal pharyngitis
Streptococcus pyogenes strains associated with
* impetigo vs
* pharyngitis
type of GN where kidneys have subcapsular hemorrhages with a “flea-bitten” appearance
Endocarditis-associated GN
Primary treatment for endocarditis-associated GN
Eradication of the infection with 4-6 weeks of antibiotics
Immune-mediated glomerulonephritis characterized by thickening of the GBM with mesangioproliferative changes; 70% of patients have hypocomplementemia
Membranoproliferative GN (MPGN)
what type of MPGN:
- Presence of subendothelial deposits;
- low C3
- Has double contour sometimes called tram-tracking
what type of MPGN:
* lntramembranous deposits, ribbon-like pattern, IgG autoantibody
* low C3
* dense deposit disease
Most proliferative of the three types of MPGN
type I MPGN
Pathologic changes of FSGS are most prominent in what part of the nephron
glomeruli located at the corticomedullary junction
GN with highest reported incidences of renal vein thrombosis, pulmonary embolism, and deep vein thrombosis
membranous nephropathy (MGN)
Pathologic change in the kidney that is a Sensitive indicator for the presence of diabetes but correlates poorly with the presence or absence of clinically significant nephropathy
thickening of the GBM
Earliest manifestation in ~40% of patients with diabetes who develop diabetic nephropathy
Increase in albuminuria detected by sensitive radioimmunoassay
Most renal amyloidosis is the result of
- Fibrillar deposits ofimmunoglobulin light chains known as amyloid L (AL),
- or secondary to fibrillar deposits of serum amyloid A (AA) protein fragments
Lesion in HIV-associated nephropathy
FSGS
GN caused by Hepatitis B
- MGN: more common in children
- MPGN: more common in adults
Schistosoma species most commonly associated with clinical renal disease
Schistosoma mansoni
Note: Schistosoma haematobium causes bladder disease
Signs and symptoms of nephrotic syndrome (4)
Diseases presenting with nephrotic syndrome (5)
vs Diseases presenting with nephritic syndrome (5
NEPHROTHIC
* MCD
* MGN
* DM Nephropathy
* Renal Amyloidosis
* FSGS
NEPHRITIC
* PSGN
* Rapidly-Progressive GN (RPGN)
* Goodpasture syndrome
* Alport syndrome
* Lupus nephropathy
Most common cause of nephrotic syndrome in Children VS elderly
- children: MCD
- elderly: MGN
Signs and symptoms of nephritic syndrome (4)
Nephrotic glomerular dse with the ff characteristics:
* Effacement of foot processes
* Highly*selective proteinuria
* good response to steroids,
* excellent prognosis
Nephrotic glomerular dse with the ff characteristics:
* Idiopathic but may be caused by SLE, hepatitis B, syphilis, gold, penicillamine, malignancy
* Diffuse capillary and BM thickening, “spike & dome appearance” with subepithelial lgG and C3 deposits
* Non-selective proteinuria, poor response to steroids, indolent course
Nephrotic glomerular dse with the ff characteristics:
* Microangiopathy leading to BM thickening
* Some patients also develop eosinophilic, PAS+ nodules called nodular glomerulosclerosis or Kimmelstiel-Wilson nodules
Nephrotic glomerular dse with the ff characteristics:
* Deposition of hyaline masses (hyalinosis) leading to obliteration of capillary lumina
Nephrotic glomerular dse with the ff characteristics:
* Subendothelialfmesangial amyloid deposits
* Apple-green birefringence on Congo red stain
Nephritic glomerular dse with the ff characteristics:
* Most common pediatric cause of nephritic syndrome
* Hypercellular glomeruli, “lumpy-bumpy” deposits of lgG and C3, subepithelial electron microscopy
* Self-resolving
Nephritic glomerular dse with the ff characteristics:
high ASO titer
Nephritic glomerular dse with the ff characteristics:
* Poststreptococcal etiology in 50%
* Renal failure within weeks or months
* Rupture of the basement membrane seen in the EM
3 types of RPGN and differentiate each type
Nephritic glomerular dse with the ff characteristics:
* Anti-GBM antibodies and anti-alveolar BM antibodies
* Linear pattern of lgG on IF
* Hematuria and hemoptysis
Nephritic glomerular dse with the ff characteristics:
* Appears before age 20
* Hereditary structural defect in collagen IV
* Leaky BM (BM splitting on electron microscope)
* Hematuria, hearing loss, blindness
in Alport syndrome, disease appears before age ____
before age 20
in Alport syndrome, there is hereditary structural defect in collagen ____
collagen IV
serum marker that correlates best with the presence of renal disease in lupus nephritis
anti dsDNA
The only reliable method of identifying the morphologic variants of lupus nephritis
renal biopsy
class of LN which has Has the most varied course
Class III
What class of LN:
Describes global, diffuse proliferative lesions involving the vast majority of glomeruli
Class IV
What class of LN:
Most common and most severe type
Class IV
What class of LN:
wire-loop lesions
Class IV
in lupus nephritis, patients with THIS PATHO FINDING on biopsy has the worst renal prognosis without treatment
crescents
Class of LN that is predisposed to renal-vein thrombosis and other thrombotic complications
Class V
Henoch-Schonlein purpura is distinguished clinically from lgA nephropathy (4)
- Prominent systemic symptoms
- Younger age (<20 years old)
- Preceding infection
- Abdominal complaints
Most common type of glomerulonephritis worldwide
lgA nephropathy
IgA nephropathy is aka
Berger’s disease
Two most common presentations of lgA nephropathy
- Recurrent episodes of macroscopic hematuria often accompanied by proteinuria during or immediately following an upper respiratory infection, OR
- Persistent asymptomatic microscopic hematuria
Antibodies more common in
* granulomatosis with polyangiitis VS
* microscopic polyangiitis or Churg Strauss
Triad of Wegener’s granulomatosis
- Necrotizing granulomas of the respiratory tract
- Necrotizing or granulomatous vasculitis
- Focal necrotizing, or often crescentic glomerulonephritis
Common cause of cholesterol emboli
Following an endovascular procedure with manipulation the aorta
Classically present with fever, purulent rhinorrhea, nasal ulcers, sinus pain, polyarthralgias/arthritis, cough, hemoptysis, shortness of breath, microscopic hematuria, and 0.5-1 g proteinuria oer 24 h
Wegener’s granulomatosis
Prototypes of Microangiopathic Hemolytic Anemia (MAHA) - (2)
- Hemolytic Uremic Syndrome (HUS) and
- Thrombotic Thrombocytopenic Purpura (TTP)
Most common variant of HUS
Shiga toxin-producing Escherichia coli (STEC) HUS, which is also known as D+ (diarrhea-associated) HUS or enterohemorrhagic E.coli (EHEC) HUS
Most common Shiga-toxigenic E. coli (STEC) strain
E.coli 0157:H7
Most severe manifestation of scleroderma characterized accelerated hypertension, rapid decline in renal function, nephrotic proteinuria, and hematuria
scleroderma renal crisis (SRC)
Autoantibody associated with development of scleroderma renal crisis
Anti RNA polymerase I and Ill
autoantibody that may identify young patients scleroderma renal crisis
Anti-U3-RNP may identify young patients scleroderma renal crisis
Renal lesion in Scleroderma renal crisis
onion-skinning
First-line therapy in SRC unless contraindicated
ACE inhibitor
Antiphospholipid antibodies (3)
BP Goal in SRC
Reduce SBP by 20 mmHg and DBP by 10 mmHg every 24 hours until BP normalized
HELLP SYNDROME(Hemolysis, Elevated Liver Enzymes, Low Platelets) commonly occurs at what trimester
third trimester
HELLP SYNDROME stands for
Hemolysis, Elevated Liver Enzymes, Low Platelets
Vein that is more commonly involved in renal vein thrombosis (RVT)
Left renal vein
Most common renal abnormality in tuberous sclerosis
Angiomyolipomas
Gitelman’s syndrome is distinguished from most forms of Bartter’s syndrome bv the presence of these 2 lab findings
- Severe hypomagnesemia
- Hypocalciuria
Acute TIN most often presents with
Acute renal failure
Predominant pathology in chronic TIN
Interstitial fibrosis
Hallmark feature of TIN with uveitis
Painful anterior uveitis
WHAT SYNDROME:
* Due to mutations affecting any of five ion transport proteins in the TAL
* Clinical syndrome mimics the effects of chronic ingestion of a loop diuretic
WHAT SYNDROME:
* Due to mutations in the thiazide-sensitive Na-Cl co transporter (NCCT) in the DCT
* Mimics the effects of thiazide diuretics
WHAT SYNDROME:
Mimics a state of aldosterone excess with early and severe hypertension, hypokalemia and metabolic alkalosis, but plasma aldosterone and renin levels are low
Triad of heavy metal (lead) nephropathy
- Saturnine gout
- Hypertension
- Renal insufficiency
Renal biopsy findings of chronic TIN
Interstitial fibrosis & tubular atrophy out of proportion to the degree of glomerulosclerosis or vascular disease
3 Normal points of narrowing in the urinary tract and common sites of stone obstruction:
- Ureteropelvic and ureterovesical junctions
- Bladder neck
- Urethral meatus
Most common type of urolithiasis
Calcium oxalate stones
renal stones associated with Proteus mirabilis, forming staghorn calculi
Struvite stones (magnesium ammonium phosphate stones)
Pathogenesis of struvite stone
Bacterial urease production
Radiopaque stones on standard x-ray (3)
Calcium, cystine, and struvite stones
Radiolucent stones on standard x-rays (1)
uric acid stones
The two main risk factors for uric acid stones
- Persistently low urine pH and
- higher uric acid excretion
Recommended target urine pH in uric acid stones
pH 6.5
For all stone types, target urine volume/day
At least 2 L/day
As part of cystine stone prevention…
Achieved by treatment with medication that covalently binds to cystine (____or ____) and a medication that raises urine pH.
tiopronin or
penicillamine
Treatment for struvite stones
complete removal by urologist
most common bacteria causing acute uncomplicated cystitis
E. coli (75-90%)
Main feature distinguishing cystitis and pyelonephritis
Fever (fever of pyelonephritis exhibits a high, spiking, “picket fence” pattern & resolves over 72 h of treatment)
fever of ____ exhibits a high, spiking, “picket fence” pattern & resolves over 72 h of treatment
fever of pyelonephritis exhibits a high, spiking, “picket fence” pattern & resolves over 72 h of treatment
antibiotics considered relatively safe for UTI in early pregnancy (3)
- Nitrofurantoin
- Penicillin
- Cephalosporins
The standard of care for pregnant women with overt pyelonephritis
Parenteral beta-lactam with or without aminoglycosides
Treatment of asymptomatic bacteriuria (ABU)does not decrease the frequency of symptomatic infections or complications, EXCEPT in these 3 populations…
- Pregnant women
- Persons undergoing urologic surgery
- Neutropenic patients and renal transplant recipients
Most common cause of bilateral hydronephrosis in boys
Posterior urethral valves
Most common cause of urinary tract obstruction in adults
Acquired defects
Pathognomonic of vesicoureteral reflux
Flank pain that occurs only with micturition
