Tubulointerstitial diseasesDownloads

An 8-year-old boy is brought to the physician by his parents because of fever for 3 days. During the period, he has had fatigue, severe burning with urination, and increased urination. The mother reports that his urine has red streaks and a “strange” odor. He has taken acetaminophen twice a day for the past two days with no improvement in his symptoms. He has had multiple ear infections in the past but has been healthy in the past year. His immunizations are up-to-date. He appears uncomfortable. His temperature is 39°C (102.2°F). Examination shows right-sided costovertebral angle tenderness. Laboratory studies show a leukocyte count of 16,000/cm3 and an erythrocyte sedimentation rate of 40 mm/hr. Urine dipstick shows leukocyte esterase and nitrites. Urinalysis shows: Blood 2+ Protein 2+ WBC 24/hpf RBC 50/hpf RBC casts none WBC casts numerous Granular casts none Urine cultures are sent to the laboratory. Damage to which of the following structures is the most likely cause of this patient's hematuria?

A 62-year-old man presents to the emergency room with an acute myocardial infarction. Twenty-four hours after admission to the cardiac intensive care unit, he develops oliguria. Laboratory tests show that his serum BUN is 59 mg/dL and his serum creatinine is 6.2 mg/dL. Renal biopsy reveals necrosis of the proximal tubules and thick ascending limb of Henle's loop. Which of the following would you most likely observe on a microscopic examination of this patient's urine?