Renal Pathology

Question 1

Normal BUN:creatinine ratio

Answer 1

10-20 mg/dL BUN:1mg/dL creatinine

Question 2

High BUN:creatinine ratio?

Answer 2

Suggests pre-renal disease

Question 3

Normal eGFR should be?

Answer 3

> 90mL/min/1.72msq

Question 4

AKI stages?

Answer 4

1) serum creatinine 1.5-1.9x increase2) 2.0-2.9increase 3) 3x increase

Question 5

Pre-renal failure

Answer 5

Hypoperfusion (septic, hypovolaemic, cardiogenic shock) or meds. Kidneys can’t clear waste so they build up systemically.

Question 6

Intra-renal causes

Answer 6

Can be drugs (antibiotics, NSAIDs, ACEi), sepsis, rhabdomyolysis

Question 7

Sulfonamide damages kidney?

Answer 7

Crystal formation obstructs tubules

Question 8

Furosemide/thyazide, NSAID, synthetic antiobiotics damage?

Answer 8

Hypersentivity

Question 9

Acute/chronic Pyelonephritis

Answer 9

Acute - chills, fever, dysuria, frequency, urgency, N&V, loin pain. Chronic (via damage to calyces and renal pelvic scarring - often by recurrent infection) leads to loss of urine concentration (polyuria and nocturia)

Question 10

ATN

Answer 10

Caused be ischaemia. Causes damage to tubules (as high mitochondria), so casts seen (epithelial slough) and nephorns lose concentrating abilities (get oliguria (blocked tubules from casts) low osmolality, high sodium in urine). Recovery beings with polyuria as patient can’t concentrate urine.

Question 11

AIN

Answer 11

Normally drug response (allopurinol, penicillins, cephalosporins, quinolones, sulfa, rifampin). But can be infection and autoimmune. Patient has rash (+/-fever), urinalysis should be done to check for AIN. URine has WBC, will have eosinophils on staining.