An otherwise healthy 43-year-old man presented with a 2-months history of mild legs and feet edema, without facial edema or ascitis.
Blood pressure 150/95, without other alterations on physical examination.
Proteinuria: 6,5 g/24h, microscopic hematuria. Normal renal function. Normal liver function tests and normal platelet count. Anti-DNA, ASLO, ANAs, hepatitis viruses, and ANCAs were all negative; there was no monoclonal spike on serum electrophoresis.
See the images.
Figure 1. H&E, X400.
Figure 2. Masson's trichrome stain, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. PAS stain, X400.
Figure 5. Methenamine silver stain, X600.
Figure 6. Methenamine silver stain, X600.
Figure 7. Immunofluorescence using antiserum to IgG, x400. Staining was diffuse.
Figure 8. Immunofluorescence using antiserum to C3, x400. Staining was diffuse.
Immunofluorescence for IgA, IgM, and C1q were negative.
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