Hepatitis in renal transplant recipients

Developments and dilemmas in renal transplantation

The number of patients waiting for a kidney transplant is about three times greater than the number of transplants performed each year. This article highlights current immunosuppression protocols and the newer immunosuppressive drugs under investigation in a number of multicenter trials. These hold out the promise of reducing the frequency of acute rejection and of prolonging graft survival. They are divided into three groups. The first, like cyclosporine, interferes with the action of interleukin 2. The second, like azathioprine, are antimetabolites; and the third, new monoclonal antibodies. The use of antibody-induction therapy is compared with standard regimens. There are risks related to prednisone withdrawal protocols and inadequate cyclosporine dosing that may lead to accelerated graft loss. Cardiovascular disease is a significant problem in older diabetic patients for whom coronary angiography is recommended. A defined set of risk factors is outlined that predicts which younger diabetic patients should have a cardiovascular evaluation. Chronic liver disease is a growing problem and rational strategies are emerging from studies of patients with biopsy-proven active hepatitis. The presence of hepatic inflammation is associated with progressive liver disease and patients must be made aware of this risk when seeking transplantation. A large number of studies of various prophylactic regimens are starting to provide data on the cost-effective reduction of cytomegalovirus disease in transplant recipients. It is recommended that patients receiving antibody therapy also receive preemptive gangciclovir. The issue of chronic allograft rejection is discussed briefly. The most important predictors of chronic allograft rejection are the frequency of acute rejection, inadequate immunosuppression, and infections.(ABSTRACT TRUNCATED AT 250 WORDS)

The impact of hepatitis C virus infection on renal allograft recipients

A second generation hepatitis C virus recombinant immunoblot assay (RIBA) was used to screen stored perioperative serum from 641 renal allograft recipients. One hundred and nine (17%) were anti-HCV positive at the time of transplant. RIBA positivity was found to be an independent predictor of post-transplant liver disease in a logistic regression model (P < 0.05). Moreover, RIBA positive patients were at greater risk for infectious events (P = 0.03) and rejection episodes (P = 0.002). The cumulative dose of antilymphoblast globulin administered as induction therapy was an independent predictor of post-transplant liver disease in a dose response relationship. Qualitative PCR showed that 74% of the perioperative RIBA positive patients had detectable HCV RNA in a current serum sample. Further, quantitative HCV RNA analysis with a competitive template PCR and HCV strain identification by restriction fragment length polymorphism demonstrated a large range of HCV RNA copies/ml of serum and three different HCV strains (BK, Hutch and HCV-1). Neither quantity of HCV RNA nor strain type correlated with abnormal transaminases post-transplant. As yet, there has not been an effect of anti-HCV status on actuarial patient and graft survival. This study suggests that anti-HCV is not a contraindication to renal transplantation; however, we would recommend that the pre-transplant evaluation of the anti-HCV positive patient include a liver biopsy to properly stage the disease. Close post-transplant follow-up is required in view of the increased risk for infection and rejection.

Hepatitis C antibodies in dialysis patients and patients with leukaemia

The prevalence of hepatitis C antibodies (anti-HCV) among multitransfused patients was studied and compared with predicted values obtained from a post-transfusion hepatitis study and from data on the prevalence of anti-HCV among blood donors. The prevalence of hepatitis B core antibodies (anti-HBc) was also studied to determine the routes of transmission of hepatitis C virus. The patients consisted of 65 dialysis patients (57 on haemodialysis and 8 on continuous ambulatory peritoneal dialysis) and 71 leukaemia patients in long-term remission [49 with acute myeloid leukaemia (AML) and 22 with acute lymphatic leukaemia (ALL)]. The presence of anti-HCV was investigated using a second generation enzyme-linked immunosorbent assay. Reactive samples were confirmed by a second generation recombinant immunoblot assay. Anti-HBc was studied in the 65 dialysis patients and in 40 of the leukaemia patients. Three (4.6%) of the 65 dialysis patients and 12 (24.5%) of the 49 AML patients were anti-HCV positive whereas all of the ALL patients were seronegative. The total number of blood units transfused to 134 patients (data on two dialysis patients were not available) was 18,148, out of which 17,575 units had been transfused prior to the initiation of anti-HCV screening of blood donors. On the basis of the anti-HCV prevalence among blood donors and the incidence of post-transfusion hepatitis, the predicted number of seropositive patients was 11 and 18, respectively. Five of the 65 dialysis patients were anti-HBc positive, compared with only one of the 40 leukaemia patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus infection among kidney transplant recipients

The extent of hepatitis C virus (HCV) infection among kidney recipients was investigated in 67 patients by testing for anti-HCV paired serum samples, collected at time of transplantation and during follow-up (average 32 +/- 20 months). Prevalence of anti-HCV at transplant time was 48%, and was related to the time on dialysis and to the amount of blood transfusions. Following transplantation, nine (28%) seropositive patients lost anti-HCV and five (14%), previously seronegative, seroconverted. Anti-HCV was found to be positive in 92% of the patients with chronic liver disease who were on hemodialysis, but in 56% in kidney recipients with chronic hepatitis. Anti-HCV was positive in 50% of patients with resolving hepatitis before transplantation, but only in 21% of those with acute hepatitis following transplantation. This study confirms the high risk of HCV infection among hemodialysis and kidney recipient populations, and also that HCV is closely related with the length of time the patient is on hemodialysis as well as the number of blood units transfused. HCV is the main cause of acute and chronic liver disease in hemodialysis patients and of chronic liver disease in kidney recipients, but does not clearly influence the survival of the allograft nor that of patients.