March 31 - Renal

Question 1

Ethylene glycol poisoning presentation

Answer 1

Initially presents similar to ethanol toxicity

24-72 hours later, get acute renal failure with tubular casts, oxalate crystals (oxalate a metabolite of ethylene glycol), and ATN due to toxicity. Anion gap metabolic acidosis. Hypocalcemia because oxalate binds up the Ca++.

Treat with fomepizole

Question 2

Contraction alkalosis

Answer 2

Decreased ECV activates RAAS. H+ secretion in proximal tubule incresaes resulting in increased bicarb reabsorption. H+ secretion also increases in collecting duct

Question 3

Acute hemolytic transfusion reaction

Answer 3

Presents with fever and chills, low BP, dyspnea, chest/back pain, and hemoglobinuria minutes to hours after strating due to ABO incompatability. Mediated by antibody and complement (type II)

Question 4

Renal papillary necrosis

Answer 4

Abrupt onset gross hematuria. Associated with sickle cell, analgesic nephropathy, diabetes, pyelonephritis. Coagulative necrosis of distal 2/3 of renal pyramids

Question 5

Hyperacute organ rejection

Answer 5

Occurs within minutes. Preformed antibodies against ABO or HLA antigens.

Rare due to cross matching. Requires prior exposure such as during pregnancy, transfusion, etc.

Vessels spasm, intravascular coagulation, ischemia

Question 6

Acute organ rejection

Answer 6

Occurs in weeks to months. T cells, esp Cd8+, react to HLA antigens. On biopsy see lymphocytic infiltrate. Treated with immunosuppression

Question 7

Chronic organ rejection

Answer 7

Occurs in months to years. Characterized by inflammation and fibrosis in vessels (or bronchioles in case of lung) Kidneys: fibrosis of capillaries and glomeruli. Heart: narrowing of coronaries. Lungs: bronchiolitis obliterans

Question 8

Varicocele

Answer 8

L sided is common as L testicular vein drains to L renal vein which drains to IVC. Aorta and SMA can compress L renal vein

R sided rare and is associated with IVC occlusion by malignant tumor or thrombus

Question 9

Myeloma cast nephropathy

Answer 9

Increased excretion of free light chains (Bence Jones proteins). Filterein in glomerulus and reabsorbed in tubule, but wehn exceed reabsorptive capacity can precipitate out with Tamm Horsfall protein. Large glassy, intensely eosionphilic casts are formed that can cause tubular obstruction and epithelial injury.

Question 10

Anti-PLA2R

Answer 10

Antibody seen in idiopathic membranous nephropathy . Found in podocytes