CASE 65 (July 2011)
The patient is a 13-year-old boy, who had nephrotic syndrome at 8 years old, with normal renal function. At this age, a renal biopsy reported type I membranoproliferative GN (studied in another center, we have not seen this biopsy and we have no images). Management was initiated with steroids, ACE inhibitors, calcium and calcitriol, without achieving adequate response, for which he received cyclosporin A, but neither was effective.
He is evaluated at our institution at the age of 12 years because he continues with nephrotic syndrome; with clinical and paraclinical characteristics similar to the first episode. The mother says he has had times of increased symptoms and periods of apparent quiescence of the disease. On physical examination: good general condition, blood pressure of 131/74 mm Hg, weight: 58 kg. Edema in both lower limbs, no other alterations.
Laboratory: complete blood cell count and coagulation studies were normal. Serum proteins: 3.2 g/dL, albumin 1.7 g/dL. Total cholesterol: 406 mg/dL, triglycerides: 243 mg/dL. Serum creatinine: 1.0 mg/dL, BUN: 16 mg/dL, creatinine cleareance: 69 mL/min. Proteinuria: 458 mg/m2/h. ANA, anti-DNA, ENA: negative. C3 and C4: normal. Viruses tests: negative.
A second renal biopsy was done. See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. H&E, X400.
Figure 4. Masson's trichrome stain, X400.
Figure 5. The same glomerulus in the previous image, amplified. Masson's trichrome stain, X400.
Figure 6. Methenamine-silver stain, X400.
Figure 7. The same glomerulus in the previous image, amplified. Methenamine-silver stain, X400.
Figure 8. PAS stain, X400.
Figure 9. Methenamine-silver stain, X400.
Figure 10. Direct immunofluorescence using antiserum to C3, X400
Figure 11. Direct immunofluorescence using antiserum to C3, tubules, X400
Immunofluorescence staining for IgA, IgG, IgM, C1q, kappa and lambda: Negative.
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