Case 59
With discussion
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CASE 59 (January 2011)

Clinical information

A previously healthy 45-year-old man went to the doctor because of malaise, which had developed in the last week. The patient reported having had a mild left ankle sports injury 20 days earlier causing him pain and edema, which had almost disappeared.

On physical examination, mild legs edema was present. There was not hypertension or other clinical alterations.

On laboratory tests, the white-cell count was 7200/mm3, erythrocyte sedimentation rate: 7 mm/h, the hematocrit was 39.2%, and the platelet count 227,000/mm3. Serum creatinine was markedly increased: 7.5 mg/dL; BUN: 98 mg/dL.

With a diagnosis of acute renal failure, other laboratory test were ordered and a renal biopsy was undertaken. See the images.

Figure 1. H&E, X200.

Figure 2. H&E, X200.

Figure 3. Masson's trichrome stain, X200.

Figure 4. H&E, X400.

Figure 5. H&E, X400.

Figure 6. H&E, X200.

Figure 7. H&E, X400.

Figure 8. Methenamine-silver stain, X400

Figure 9. Methenamine-silver stain, X400

Direct immunofluorescence for IgA, IgG, IgM, C3, C1q, kappa and lambda: negative.

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