A case of acute humoral rejection with various depositions of C4d, IgG, IgM, and C3c in peritubular capillaries and/or glomerular capillaries

Abstract

A 41-year-old Japanese male patient with end-stage renal disease received ABO compatible living related kidney transplantation from his sister on April 2003. The kidney functioned immediately after kidney transplantation. Protocol allograft biopsy at 1 yr after kidney transplantation was performed on April 2004. His serological data was not particular and he did not suffer with chronic inflammation. The allograft biopsy specimen revealed moderate accumulations of polymorphonuclear leukocytes in peritubular capillaries (PTCs), dilatation of PTCs and moderate infiltrations of polymorphonuclear and/or mononuclear cell in glomeruli (Transplant glomerulitis, moderate). Immunofluorescent study (IF) of a frozen section of the allograft biopsy specimen showed a strong, diffusely distributed endothelial-staining pattern in PTCs for C4d. The C4d was also strongly detected in a linear glomerular basement membrane (GBM) pattern. And widespread moderate C3c deposits, weak IgM, and IgG deposits were also seen in PTCs. Immunofluorescent study also showed granularly peripheral and mesangial deposits of strong IgM, C1q, and moderate IgG in glomeruli, IgA and C3c were faintly positive. The panel reactive antibody, which had been negative before transplantation, was positive for both HLA classes I and II at that time. We diagnosed as acute humoral rejection (AHR) and he was treated with course of steroid pulses and 5 d of gusperimus (DSG); and a total of three times Plasma exchange (PE) treatment was added. The level of serum creatinine, once increased to 1.7 mg/dL, decreased gradually to 1.4 mg/dL. He has a stable graft function. This is the only case of various depositions of immunoglobulins and complements in PTC and/or glomerular capillaries during AHR.