CASE 21 (November 2007)
The patient is a 32-year-old man (in 2007) with history of unknown cause end-stage renal disease. He started hemodialysis in 1999 and he was kidney transplanted in 2000. A graft rejection was diagnosed in the first three post-transplant months, without biopsy, and it was treated with steroid boluses. Allograft function was not newly altered in the first six years: serum creatinine between 1.0 mg/dL and 1.5 mg/dL, without proteinuria nor hematuria. The patient has systemic arterial hypertension and he does not have diabetes. Immunosuppression: cyclosporine, mycophenolate mofetil, and prednisolone.
In August 2006 serum creatinine increased to 1,6 mg/dL and the levels continued increasing until 2,6 mg/dL in March 2006. A renal biopsy was undertaken.
Urinalysis: Proteinuria: 160 mg/24h, 2 erythrocytes HPF, without casts.
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See the images.
Figure 1. H&E, X400.
Figure 2. Masson's trichrome stain, X400.
Figure 3. PAS stain, X400.
Figure 4. Methenamine silver stain, left X400, right, X600.
Figure 5. Methenamine silver stain, left X400, right, X600.
Figure 6. Methenamine silver stain, left and right, X400.
Figure 7. Immunohistochemistry for C4d, X400.
Immunofluorescence for IgA, IgG, IgM, C3, and C1q were negative.
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