248. The answer is b. (Fauci, 14/e, p 1544.) IgA nephropathy (Berger's) is the most commonly encountered form of focal glomerulonephritis worldwide, and patients will often have microhematuria. It may follow an upper respiratory tract infection or physical exertion. Bladder cancer is a common cause of asymptomatic microhematuria but is usually found in patients over the age of 50. Risk factors for bladder neoplasia include aniline, rubber, other organic solvents, industrial dyes, and tobacco use. Minimal change disease almost always presents with severe proteinuria, and erythrocyte casts are not seen in rhabdomyolysis. Patients with Alport syndrome have the nephritic syndrome and hearing loss.
249. The answer is c. (Fauci, 14/e, p 2529. Tierney, 39/e, p 901.) Indications for dialysis are easily remembered with the vowel mnemonic of A, E, I, O, U or Acidosis (pH < 7.20), Electrolyte abnormality (hyperkalemia), fluid Overload unresponsive to diuretics, and Uremic symptoms (pericarditis, encephalopathy, or coagulopathy). The I in the mnemonic is a reminder that ingestion of certain drugs (barbiturates, bromide, chloral hydrate, ethanol, ethylene glycol, isopropyl alcohol, lithium, methanol, procainamide, theo-phylline, salicylates, and heavy metals) is treatable with dialysis.
250. The answer is c. (Fauci, 14/e, pp 1559-1560.) Renal artery stenosis (RAS) accounts for <5% of hypertension (HTN). The most common cause is atherosclerosis, but in young women the etiology is often fibro-muscular dysplasia. Patients may present with a high-pitched epigastric bruit. A positive captopril test (renin values increase greatly after a dose of the angiotensin converting enzyme is given, because the drug magnifies the impairment in blood flow and in the glomerular filtration rate caused by the RAS) is an excellent screening procedure. The diagnosis is then confirmed with a digital subtraction renal arteriogram. Patients with pheo-chromocytoma often present with sudden episodes of hypertension, headache, profuse sweating, anxiety, and palpitations. The diagnosis is made by 24-h urine collection for catecholamines or catecholamine metabolites. Patients with HTN due to coarctation of the aorta present with delayed or absent femoral pulses and complain of claudication. Patients with primary hyperaldosteronism (Conn syndrome) (etiology is usually bilateral adrenal hyperplasia) present with HTN, fatigue, polyuria, and muscle weakness due to potassium depletion. Cushing's disease is characterized by central deposition of adipose tissue, muscle weakness, amen-orrhea, impotence, psychiatric abnormalities, and HTN.
251. The answer is b. (Goldman, 21/e, p 635.) Definitive risk factors for prostate cancer include African American race and family history of prostate cancer. Potential risk factors for prostate cancer include a diet high in fat, a diet low in selenium, and, perhaps, having undergone a vasectomy.
252. The answer is e. (Fauci, 14/e, pp 268-269, 2007.) The patient presented with euvolemic hyponatremia secondary to primary polydipsia (compulsive water consumption). Since the hyponatremia developed gradually in the absence of neurologic symptoms (i.e., seizures), it should not be corrected rapidly. The appropriate rate of correction should be 12 meq/24 h to prevent central pontine myelinolysis (CPM), which is an osmotically induced demyelination due to overly rapid correction of serum sodium. Patients develop paraplegia, quadriplegia, and coma. 253. The answer is e. (Fauci, 14/e, p 261.) An easy mnemonic to address hematuria is "If your doctor does not know how to work up hematuria, you should SWITCH GPS."
S = Stones, sickle cell disease, sickle cell trait, scleroderma, SLE, sulfon-amides
W = Wegener's granulomatosis I = Infections, instrumentation, iatrogenic, interstitial nephritis T = Trauma, TB, tubulointerstitial disease, tumor, thrombocytopenic thrombotic purpura (TTP) C = Cryoglobulinemia, cyclophosphamide
H = Hemolytic-uremic syndrome, hypercalciuria, hemophilia, Henoch-
Schonlein purpura G = Goodpasture's disease, glomerulonephritis P = Papillary necrosis, polycystic kidney disease, polyarteritis nodosa S = Schistosomiasis, sponge disease (medullary sponge disease)
254-255. The answers are 254-b, 255-c. (Fauci, 14/e, pp 592-596.) Ninety-five percent of tumors of the kidney are renal cell carcinomas. Patients present with hematuria and the presence of an abdominal mass. Causal factors have been implicated in the development of renal cell carcinoma, but cigarette smoking and obesity are the strongest associations. Bladder cancer is strongly associated with cigarette smoking and chemical compounds (aromatic hydrocarbons). Chimney sweepers and dry cleaners are also at risk for bladder cancer (up to 25% of all bladder cancer is occu-pationally related). Cancer of the ureter (transitional cell like the bladder) is associated with chronic phenacetin use, cigarette smoking, and hydrocarbon chemical exposure.
This page intentionally left blank.
Was this article helpful?