Nephrology

Question 1

Best diagnostic test for monoclonal gammopathy of renal significance (MGRS)

Answer 1

Kidney biopsy

Consider dx if has MGUS with renal involvement

Question 2

Isovolemic hypotonic hyponatremia with urine osm <100 is indicative of what?

Answer 2

Excessive water intake (psychogenic polydipsia) or poor solute intake

In DI or nephrogenic DI, serum sodium is usually normal or elevated

Question 3

Diabetic nephropathy findings

Answer 3

Proteinuria after longstanding diagnosis (>8 years)

Kidney biopsy not required, treat with ACE

Question 4

Secondary causes of hypoaldo/hyperkalemia

Answer 4

Heparin (unfractionated and LMWH)
RTA type 4
RAS inhibitors
Primary adrenal disease

Question 5

Clinical findings in ANCA vasculitis

Answer 5

Prodromal malaise, arthralgia, myalgia, skin findings with hematuria, proteinuria and AKI

Question 6

Differential diagnosis for RPGN

Answer 6

1) Pauci-immune staining (ANCA-associated)
2) Linear staining (anti-GBM)
3) Granular staining (lupus nephritis)

Question 7

Confusion, AGMA, negative lactate with history of chronic liver/kidney disease or poor nutrition

Answer 7

Pyroglutamic acidosis

Question 8

AGMA, intermittent confusion, slurred speech, ataxia, short bowel syndrome

Answer 8

D-lactic acidosis

Question 9

Treatment for acute hyponatremia

Answer 9

3% normal saline (100 mL bolus)

Ecstasy induces hyponatremia via ADH release and often induces patients to drink large volumes of water

Question 10

Treatment for recurrent calcium stones

Answer 10

thiazide diuretics

Induces sodium resorption (via dehydration) which induces passive calcium resorption and thus reduced urinary calcium

Question 11

Fluid choice for alcoholic ketoacidosis

Answer 11

dextrose and normal saline

Dextrose to induce insulin secretion and reduce ketone formation. Isotonic saline is for rehydration.

Question 12

Treatment for edema with nephrotic syndrome

Answer 12

Loop diuretics

Add thiazide or potassium-sparing diuretic (e.g. metolazone) if suboptimal response to maximum tolerated loop diuretic dose.

Decreasing GFR requires increased diuretic dose

Question 13

Risk factors for secondary FSGS

Answer 13

Premature birth, obesity

Subnephrotic proteinuria, typically no clinical findings

Secondary FSGS is attributed to hyperfiltration injury in setting of reduced renal mass –> adaptive podocyte injury and segmental sclerosis

Question 14

Differentiate between saline-responsive and saline-resistant metabolic alkalosis

Answer 14

Responsive: urine chloride < 15
- consider volume contraction, GI loss, surreptitous vomiting

Resistant: urine chloride >15
- consider hyperaldosteronism, Cushing, Bartter and Gitelman

Question 15

Preferred vascular access for G4 CKD

Answer 15

Central&raquo_space; peripheral (e.g. PICC)

Question 16

Cutoffs for potassium wasting

Answer 16

Urine potassium > 20 mEq/24hr, spot U potassium >20 mEq/L, spot urine potassium/creatinine >13 mEq/g

In poor nutritional states (rare in hypokalemia), Urine potassium would be < 20

Question 17

Infection-related GN with cellulitis present at the same time. Organism?

Answer 17

Staph - more likely to induce IRGN at the time of the infection

Strep species typically have a 1-4 week delay between primary infection and GN

Question 18

Phosphate binders

Answer 18

Sevelamer (non-calcium binder), preferred

Aluminum hydroxide - useful for very short-term treatment of symptomatic hyperphosphatemia. May side effects.

Cinacalcet - calcimimetic that decreases PTH, used for ESRD

Question 19

Infectious associations with Membranous GN, Membranoproliferative GN, FSGS

Answer 19

Membranous: Hep B
Membranoproliferative: Hep C
FSGS: HIV

Question 20

Hypertension, Gout, CKD with history of working as a mechanic.

Answer 20

Lead nephropathy

Causes chronic tubulointerstitial nephritis

Question 21

Negative urine AG suggests what in NGMA?

Answer 21

GI loss

UAg: Urine Sodium + Urine Potassium - Urine Chloride

Question 22

Teratogenic medications in renal transplant patients

Answer 22

Mycophenolate mofetil
Sirolimus
Everolimus

Calcineurin inhibitors (cyclosporine/tacro) have been well tolerated in pregnancy

Question 23

Treatment for hepatorenal syndrome type 1

Answer 23

Vasoconstriction (octreotide, midodrine) and IV albumin

Also discontinue diuretics, restrict sodium, restrict water if hyponatremic

Definitive therapy is transplant, TIPS is used for selected patients (e.g. active variceal bleeding)

HRS T1 - onset w/in 48 hours, elevated Cr (>0.3 above baseline), other etiologies ruled out, bland urine sediment, low UNa

Question 24

When are thiazide diuretics less effective?

Answer 24

GFR <30

Good for initial therapy for HTN, less effective in CKD

Question 25

Features of cisplatin-induced renal injury

Answer 25

AKI
Polyuria
Tubular injury
Hypomagnesemia
Proximal (Type 2) RTA
Fanconi

Question 26

Follow up interval for simple cysts

Answer 26

None, reassurance is appropriate (malignancy risk <1 %)

Features of simple cyst:

• round, thin, smooth, regular border
• no septa, calcifications, or solid components
• posterior enhancement on U/S
• no contrast enhancement on CT/MRI

No follow up imaging is indicated

Question 27

Findings in calcineurin inhibitor nephrotoxicity

Answer 27

Decreased GFR
Hyperkalemia
Hyperuricemia
Hypophosphatemia
Hypomagnesemia

Consider if CYP450 inhibitor s are being prescribed with tacro/cyclosporine

Question 28

Urine findings for following stone types

1) Calcium oxalate
2) Uric acid
3) Struvite
4) Cystine

Answer 28

1) Envelope-shaped crystals.
- Hx of hyperparathyroidism, RTA, or malabsorption
2) Rhomboid crystals, radiolucent stones.
- Hx of gout or myeloproliferative disorders
3) Staghorn calculi, coffin-lid crystals
- Hx of recurrent UTI
4) Hexagonal yellow/green crystals, branched calculi
- AR, multiple stones