aeltorai USMLE.org practice test Question and Answer

A 25-year-old woman has a 3-day history of vomiting and diarrhea. She has postural hypotension and poor tissue turgor. Her serum sodium concentration is 130 mEq/L. Which of the following findings is most likely? - Increased serum ADH (vasopressin) concentration A 52-year-old woman 2-day history of fever and left flank pain. She has been treated for multiple episodes of pyelonephritis. Physical examination shows left flank tenderness. Urinalysis shows WBCwith features of macrophages. Cultures of urine grow Proteus mirabilis. An x-ray shows a 3-cm mass in the lower pole of the left kidney. Gross examination of the mass after it has been resected shows that it is yellow, and centrally but not marginally necrotic. Histologic examination of the mass shows a predominance of epithelioid cells with partially clear and granular-to-foamy cytoplasm. Nuclei are eccentric, normochromic, symmetric, and without significant pleomorphism. Scattered lymphocytes and plasma cells are intermixed. Which of the following is the most likely diagnosis? - Xanthogranulomatous pyelonephritis A 50-year-old man with a history of alcoholism has difficulty with short-term memory. He is unable to recall the date and cannot remember what he ate for breakfast this morning. He thinks the examiner is a long-lost friend and carries on a conversation with the examiner as if they have known each other for years. His long-term memory appears intact. The patient dies shortly thereafter of a myocardial infarct. Pathologic examination of his brain is most likely to disclose an abnormality involving which of the following? - Mammillary bodies A 72-year-old man who is a retired construction worker comes to the physician because he has had a lesion on his face for 3 months. Physical examination shows a 6-mm, red, ulcerated lesion with heaped borders. A biopsy specimen of the lesion shows atypical, dysplastic keratinocytes within the epidermis and dermis. Which of the following is the most likely diagnosis? - Squamous cell carcinoma A 1-day-old newborn is evaluated for possible sepsis. Blood cultures grow gram-positive cocci in pairs and chains that agglutinate with group B antiserum. The most likely epidemiologic risk factor for this infection involves bacterial colonization of which of the following? - Mother's vagina