CASE 66 (August 2011)
The patient is a 15-year-old boy. He had end-stage renal disease due to severe vesicoureteral reflux. He was transplanted 2 years ago (deceased donor). In the last medical examination proteinuria was found: 1.8 mg/24h. Normal renal function. In urine: 4-5 erythrocytes/HPF without leukocytes or casts. No alterations in other organs; there is not hypertension. Immunosuppression with cyclosporine, prednisone and mycophenolate. Because proteinuria and microhematuria a renal biopsy was taken.
See the images.
Figure 1. H&E, X100.
Figure 2. H&E, X400.
Figure 3. Masson's trichrome stain, X400.
Figure 4. PAS stain, X400.
Figure 5. Methenamine-silver stain, X400.
Figure 6. There are not "spikes". Methenamine-silver stain, X400.
Figure 7. There is not peritubular capillaritis. Methenamine-silver stain, X400.
Figure 8. Direct immunofluorescence using antiserum to IgG, X400.
Figure 9. Immunostaining for C4d, X400. Diffuse staining in PTC.
Immunofluorescence staining for IgA, IgM, C3, and C1q: Negative.
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