CASE 74 (April 2012)
The patient is a 36-year-old woman. She presented dysuria and urinary frequency 10 days prior to the current clinical evaluation. She started empirical treatment with ciprofloxacin, 500 mg every 6 hours, at the suggestion of a pharmacist. She also ingested ibuprofen and a "natural" product with the name "Flor de Jamaica". Urinary symptoms improved. Now she is evaluated due to 3 days of abdominal pain, nausea, emesis, and malaise; she in additiom used diclofenac and metoclopramide.
On physical examination: Good general condition, pale, BP: 112/78, HR: 80, RR: 16, no fever or skin lesions, no edema, no ascites. No cardiopulmonary alterations.
Laboratory: Serum creatinine: 9.0 mg/dL, BUN: 44.0 mg/dL. K: 4.9 meq/L, Na: 142 meq/L. Blood count: Normal. Urinalysis: pH: 7.0, Density: 1,010, proteins: negative, sediment: erythrocytes: 2-4/HPF, leukocytes: 8-10/HPF, bacteria: negative, nitrite: negative. ANA, anti-DNA, ANCA: Negative. Serum complement: normal. Electrophoresis of proteins: Normal. Hepatitis viruses and HIV: Negative. Renal ultrasound: RK: 10.6 X5, 3X6 cms LK: 10.1 X5, 3X5, 3 cm. Bilateral diffuse increase in echogenicity, corticomedullary differentiation preserved.
With diagnosis of acute renal failure, a renal biopsy was undertaken. See the images.
Figure 1. H&E, X100.
Figure 2. Masson's trichrome stain, X100.
Figure 3. Masson's trichrome stain, X100.
Figure 4. PAS, X100.
Figure 5. H&E, X400.
Figure 6. Masson's trichrome stain, X400.
Figure 7. Methenamine-silver stain, X400.
Direct immunofluorescence for IgA, IgG, IgM, C3, C1q, kappa, and lambda: Negative.
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