CASE 153 (November 2018)
A 29-year-old man presented with edema and hypertension of several months of evolution. Nephrotic proteinuria is documented: 4.2 g/24h, mild hypoalbuminemia and dyslipidemia, serum creatinine 2.4 mg/dL, BUN: 45 mg/dL. In uroanalysis: proteinuria: 500 mg/dL, 15-20 red blood cells/hpf, scarce waxy casts. No extrarenal alterations different from what has already been noted. Studies of autoimmunity and infections were negative.
See the images of the renal biopsy.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. PAS, X400.
Figure 4. PAS, X400.
Figure 5. Masson's trichrome stain, X200.
Figure 6. Methenamine-silver, X400.
Figure 7. Methenamine-silver, X400.
Figure 8. Methenamine-silver, X400.
Figure 9. EM, X2,500.
Figure 10. EM, X2,500.
Figure 11. Direct immunofluorescence for IgA, X400.
Figure 12. Direct immunofluorescence for IgG, X400.
Figure 13. Direct immunofluorescence for C3, X400.
Direct immunofluorescence for IgM and C1q: Negative.
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