CASE 121 (March 2016)
A 13-year-old girl with no medical history presented with a week of edema, malaise and headache. On physical examination there is generalized edema, BP: 140/95. No skin lesions. No other alterations.
Paraclinical: Hb: 14 mg/dL, Ht: 41.5%, normal white blood cell count and platelets. ANA and anti-DNA: negative; C3: 62 mg/dL (90-180), C4: 17 mg/dL (10-40). Serum creatinine 1.9 mg/dL, BUN 29 mg/dL. Studies for viruses: negative. ASLO: 160 U/dL (<200 U/dL). Urinalysis: erythrocytes: 20-30/CGA; leukocytes: 6-8/CGA, nitrites negative, proteinuria 1.7 g/24h.
A renal biopsy was done, see the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. H&E, X400.
Figure 4. Methenamine-silver, X400.
Figure 5. PAS, X400.
Figure 6. Masson's trichrome stain, X400.
Figure 7. Direct immunofluorescence for IgG, X400.
Figure 8. Direct immunofluorescence for C3, X400.
Figure 9. Direct immunofluorescence for C3, X400.
Figure 10. Electron microscopy, X4,000. (Image courtesy of Dr. Carlos Andrés Jiménez).
Direct immunofluorescence for IgA, IgM and C1q: Negative.
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