CASE 82 (December 2012)
The patient is a 17-year-old woman with no medical history, who consults for edema in legs and malaise. She presents mild hypertension, but no other abnormalities on physical examination.
Paraclinical: Hct: 38%, Hb: 12.1 mg/dL, platelet 280,000, Normal leukogram. ANA and anti-DNA negative. C3: 63 (90-180), C4: 18 (10-40). Tests for viruses: negative. Serum creatinine: 1.6 mg/dL, BUN 42 mg/dL, creatinine clearance: 34 mL/min. Urinalysis: proteins: 300 mg/dL, 8-10 erythrocytes/HPF, without casts. Proteinuria in 24 hours: 2.9 g.
A renal biopsy is undertaken: in histologic sections there are only two glomeruli; there are not tubulointerstitial alterations. See the images.
Figure 1. H&E, X400.
Figure 2. H&E, X400.
Figure 3. PAS, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. Masson's trichrome stain, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Immunofluorscence for C3, X400.
Figure 9. Immunofluorscence for C3, X400.
Direct immunofluorescence for IgA, IgG, IgM, C1q, kappa, and lambda: Negative.
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