SEX MISMATCH AS A RISK FACTOR FOR CHRONIC REJECTION OF LIVER ALLOGRAFTS

Chronic irreversible rejection is a major cause of graft loss and retr ansplantation after orthotopic liver allotransplantation. To identify risk factors we retrospectively analysed 423 adult consecutive primary liver allograft recipients. The endpoint of the study was graft failu re due to chronic rejection leading either to retransplantation or dea th. Chronic rejection developed in 22 (5.2%) patients. Pretransplant d iagnosis of primary biliary cirrhosis or autoimmune hepatitis, recipie nt age less than 30 years, 1 or more episodes of acute cellular reject ion, and transplantation of an organ from cytomegalovirus (CMV). IgG p ositive donor to an IgG negative recipient were identified as risk fac tors for chronic rejection. Transplantation of a liver from a male don or into a female recipient was also associated with an increased proba bility of chronic rejection. By logistic regression analysis, the prob ability of chronic rejection was predicted by: sex and cytomegalovirus match of donor and recipient, the presence of acute rejection, recipi ent age, transplantation for autoimmune hepatitis or primary biliary c irrhosis, and recipients receiving no azathioprine during the third mo nth after transplantation. Sensitisation to antigens expressed by bile -duct epithelium as in primary biliary cirrhosis or exposure to donor bile-duct minor histocompatibility antigens, such as the male sex rela ted H-Y antigen, may provide an explanation, More selective allocation of donor organs may allow a reduction in the incidence of ductopaenic rejection and graft loss.