CASE 119 (January 2016)
The patient is a 48-year-old man, kidney transplanted five months ago by ESRD of unknown cause. He presented in the firsts post-transplantation months de novo diabetes mellitus and pyelonephritis which responded well to treatment. In a control his serum Cr is 3.88 mg/dL (one month before 1.5 mg/dL), BUN 52 mg/dL. Immunosuppression: PDN, tacrolimus, MMF. Tacrolimus levels within the therapeutic range. Asymptomatic. Urine with volume and appearance normal. Proteinuria: 30 mg/dL, erythrocytes: 10/hpf. Negative urine culture. On physical examination: normal, no edema.
Suspecting acute rejection, a renal biopsy was done, see the images.
Figure 1. H&E, X200.
Figure 2. H&E, X200.
Figure 3. H&E, X400.
Figure 4. H&E, X400.
Figure 5. H&E, X400.
Figure 6. H&E, X400.
Figure 7. Masson's trichrome stain, X400.
Figure 8. Masson's trichrome stain, X400.
Figure 9. Immunohistochemistry for kappa light chains, X400.
Figure 10. Immunohistochemistry for kappa light chains, X400.
Figure 11. Immunohistochemistry for lambda light chains, X400.
Direct immunofluorescence for IgA, IgG, IgM, C3 and C1q: Negative. Immunohistochemistry for C4d and SV40: Negative.
What is your diagnosis?