CASE 158 (April 2019)
A 10-year-old girl with no pathological personal history was referred because of edema of 2 months of evolution. Complete nephrotic syndrome was documented. Serum creatinine: 0.7 mg/dL, BUN: 14 mg/dL. Proteinuria: 3.4 g/day (140 mg/m2/h). In uroanalysis there was microhematuria, without casts in the sediment. Serum C3: 42 mg/dL (90-180), C4: 14 mg/dL (10-40) ANA and anti-DNA: Negative. Studies for infections: Negative. No extrarenal manifestations were found other than those of the nephrotic syndrome. There was no family history of renal disease
See the images of the renal biopsy.
Figure 1. H&E, X400.
Figure 2. H&E, X400.
Figure 3. PAS, X400.
Figure 4. PAS, X400.
Figure 5. Masson's trichrome stain, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Direct inmunofluorescence for C3, X400.
Figure 9. Direct inmunofluorescence for C3, X400; (staining in basement membranas of tubuli).
Figure 10. Electron microscopy, original magnification, X4,000.
Direct immunofluorescence for IgA, IgG, IgM, C1q, kappa, and lambda: Negative.
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