CASE 39 (May 2009)
The patient is a 13-year-old girl. She has presented nephrotic syndrome since the age of two, 1-2 recurrences at year, with good response to steroids. No other pathologic antecedents.
She was evaluated by nephrologist due to one week of general malaise, edema and macroscopic hematuria. These features were not presented in previous episodes of nephrotic syndrome.
On physical examination: blood pressure 130/80 mm Hg, heart rate: 88/min, respiratory rate: 16/min. Facial and legs edema. Skin lesions with papulo-nodular appearance, some of them with erythema. No other alterations.
Laboratory tests: blood cells count: normal. Proteinuria: 53 mg/m2/h, leucocytes: 18 hpf; erythrocytes: 50 hpf; granular and erythrocytaire casts. Serum creatinine: 1.2 mg/dL; BUN 29 mg/dL.
ANAs and anti-DNA: negative. C3: 58 (90-180); C4 23.3 (10-40).
See the images of the renal biopsy.
Figure 1. There are some small foci of tubulointerstitial inflammation. H&E, X100.
Figure 2. H&E, X200.
Figure 3. H&E, X400.
Figure 4. H&E, X400.
Figure 5. H&E, X400.
Figure 6. Masson's trichrome stain, X400.
Figure 7. Methenamine-silver stain, X400.
Figure 8. Direct immunofluorescence using antiserum to IgG, X400.
Figure 9. Direct immunofluorescence using antiserum to C3, X400.
Figure 10. Direct immunofluorescence using antiserum to C1q, X400.
Direct immunofluorescence for IgA and IgM: Negative.
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