CASE 41 (July 2009)
The patient is a 21-year-old woman. She had end-stage renal disease of unknown cause. After 4 months on hemodialysis she was kidney transplanted from a brain dead donor. Good initial graft function. Immunosuppression with cyclosporine, mycophenolate and prednisone. She presented two episodes of acute rejection during the first post-transplantation year, one of them proved by biopsy (Figure 1); both episodes were treated with steroid boluses and there was good response. In the second year ureteral stenosis was documented and it was surgically corrected. The serum creatinine was between 1.1 and 1.6 mg/dL.
At 37 post-transplantation months there was serum creatinine increase: 2.4 mg/dL. By ultrasound hydronephrosis and ureteral stenosis were found, then a surgical procedure was carried out. In this procedure an ureteral fragment, 1 cm in length, was resected and microscopically studied (Figures 2-6).
See the images.
Figure 1. First biopsy, 6 post-transplantation months; T-cell mediated acute rejection, Banff type IB; no arterial lesions. Left: H&E, X200; right: Masson's trichrome stain, X400.
Figure 2. H&E, X100.
Figure 3. H&E, X100.
Figure 4. H&E, X200.
Figure 5. Masson's trichrome stain, X200.
Figure 6. H&E, X400.
Immunohistochemistry for C4d on renal biopsy and ureter: Negative.
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