1. AOA NEPHROLOGY REVIEW March 18, 2009

2. A 29 year old woman is being evaluated to find the cause of her urine turning a dark brown color after a recent upper respiratory tract infection. She has been otherwise asymptomatic, and her blood pressure has been within normal limits. Urinalysis finds moderate blood present with red cells and red cell casts. Immunofluorescence examination of a renal biopsy reveals deposits of IgA within the mesangium. These clinical findings suggest that her disorder is associated with activation of the alternate complement system. Which of the follow serum laboratory findings is most likely? Serum C2Serum C3Serum C4 A  normal B  C  D   E 

3. A 28 year old man with a history of malaise and hemoptysis presents with the acute onset of renal failure. Laboratory examination reveals increased serum creatinine and BUN, but no antineutrophil cytoplasmic antibodies (ANCA) nor antinuclear antibodies (ANA) are present. Urinalysis reveals the microscopic presence of red blood cells and red blood cell casts, which a renal biopsy reveals crescents within Bowman’s space of many glomeruli. Immunofluorescence reveals linear deposits of IgG and C3 along the glomerular basement membrane. Which of the following is the most likely diagnosis? A Alport syndrome B Diabetic glomerulopathy C Goodpasture syndrome D Henoch-Schölein purpura E Wegener’s granulomatosis

4. A toddler is brought to you with swelling of the hands and face. The mother says he was well but fell from his bike 2 weeks ago. Examination shows an elevated blood pressure and an infected wound of the shin. Urinalysis shows numerous red blood cells. Which statement is true? A Hypertension due to sodium retention B The causative organism is Staphylococcus C Complement levels will remain depressed for up to 6 months D The child will likely develop chronic renal failure if untreated E The facial swelling is due to nephrotic syndrome

5. A 28 year old woman is brought to the ER after developing hypokalemic paralysis. Arterial blood gas analysis shows a PaO 2 of 102 mmHg and a pH of 7.1. She is diagnosed with type I renal tubular acidosis caused by Sjögren’s syndrome (autoimmune tubulointerstitial nephropathy that damages the H+- ATPase on the distal nephron). Which of the following laboratory measurements will most likely be normal in this patient? A Net acid excretion B Aldosterone secretion C Serum bicarbonate D Urine ammonium E Anion gap

6. An elderly male presents with urinary frequency. Laboratory examination showed an elevated serum creatinine. On physical examination you detect an enlarged prostate. Which other finding is most likely? A Pain on urination B Oliguira C Hypokalemia D Metabolic acidosis E Normal renal ultrasound

7. A 23 year old male is brought to the ER after collapsing during basketball practice. On admission he is lethargic and appears confused. His coach reports that he was drinking a lot of water during practice. His symptoms are most likely caused by increased: A Intracellular tonicity B Extracellular tonicity C Extracellular volume D Intracellular volume E Plasma volume

8. A 70 year old man presents to you because he has not been feeling well for several months. He mainly complains of malaise and achiness. He takes ibuprofen occasionally for these symptoms. His urine shows protein and erythrocyte casts. A 24 hour urine shows 1g of protein per day. His creatinine clearance is 24 ml/min. About 4 months ago, his serum creatinine was normal. The most likely diagnosis is: A Amyloidosis B Light chain deposition disease C Non-steroidal induced interstitial nephropathy D Vasculitis E HIV nephropathy

9. A medical student presents to the ER with a 2 day history of severe vomiting and orthostatic hypotension. What kind of metabolic abnormalities are most likely in this patient? A Hypokalemia, hypochloremia, metabolic acidosis B Hyperkalemia, hyperchloremia, metabolic alkalosis C Normal serum electrolytes and metabolic acidosis D Normal serum electrolytes and metabolic alkalosis E Hypokalemia, hypochloremia, metabolic alkalosis

10. A 32 year old male with AIDS presents with moderate proteinuria and hypertension. Histologic sections of the kidney reveal the combination of normal appearing glomeruli that have deposits of hyaline material. No increased cellularity or necrosis is noted in the abnormal glomeruli. Additionally there is cystic dilation of the renal tubules, some of which are filled with proteinaceous material. Electron microscopy reveals focal fusion of podocytes, and immunofluorescence finds granular IgM/C3 deposits. Which of the following is the most likely diagnosis? A Diffuse proliferative glomerulonephritis B Focal segmental glomerulonephritis C Focal segmental glomerulosclerosis D Membranous glomerulopathy E Minimal change disease

11. A patient with a history of cirrhosis and small cell lung cancer comes to the office for routine bloodwork, which reveals of serum sodium of 120. Which laboratory test is most useful in determining which of these two diseases is the cause of the hyponatremia? A Serum osmolarity B Serum creatinine C Urine osmolarity D Urine sodium E Serum vasopressin