A 38-years-old man, farmer, without previous diseases, presented with three weeks of progressive edema, oliguria, and acute renal failure, without macroscopic hematuria. On physical examination, he appeared well but uncomfortable owing to the generalized edema. The blood pressure was 150/95 mm Hg, the pulse 88 beats per minute, and the temperature 36.8°C. The patient was awake, alert, and oriented. He presented uremic breath.
Laboratory tests: Hb: 13.5 mg/dL, Hto. 48%; white cells: 7,700 per mm3, platelets: 300,000 per mm3, creatinine 11.2 mg/dL (10 days previously: 1.8 mg/dL), BUN 135 mg/dL.
Urinalysis: pH: 5.0; density: 1,005; proteins: 17 g/24h., with volume 400 cc; erythrocytes: 300 HPF.
Cholesterol: 663 mg/dL; LDL: 552 mg/dL; tryglycerids: 376 mg/dL. Calcium: 6,9 meq/L; Na: 136 meq/L; K: 5.0 meq/L. Renal ultrasound: normal. Serum complement levels: normal, ANAs negative. AgSVHB, AcVHC, HIV: negative. Bence-Jones protein: positive, with normal electrophoresis in serum.
A renal biopsy was undertaken and immunosuppression was started without a good response. Creatinine was 2.1 mg/dL at discharge, without dialysis. A month later of the immunosuppression was started he presented sepsis and died 24 hours after hospital re-admission.
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See the images.
Figure 1. Collapsed glomerulus with loss capilar lumen. H&E, x400.
Figure 2. Characteristic tubulointerstitial disease usually is present along with glomerular lesions. Masson's trichrome stain, X100.
Figure 3. Hypertrophy and hyperplasia of podocytes are a part of the lesions' spectrum. Masson's trichrome stain, X400.
Figure 4. Collapsing lesions can be segmental (the present image) or global. Masson's trichrome stain, X400.
Figure 5. Silver staining permits to see clearly the tuft collapse (see figures 6 and 7 too). Methenamine silver stain, X400.
Figure 6. Methenamine silver stain, X400.
Figure 7. Methenamine silver stain, X400.
Immunofluorescence for IgA, IgG, C3, C1q, Kappa, and Lambda, were negative. There was slight positivity for IgM, focal and segmentary, in glomeruli.
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