Background and Aim: Occult HCV infection (OCI) is characterized by the presence of HCV- RNA in liver or in peripheral blood mononuclear cells in the absence of serological markers. Infection with HCV is and independent risk factor for graft loss and is associated with proteinuria, chronic rejection, transplant glomerulopathy, posttransplant diabetes and HCV- associated glomerulopathies. However, the prevalence and relationship between kidney outcome and OCI are unknown.
The aim of the study is to know the prevalence of OCI in recipients of kidney transplantation and investigate possible clinical implications of OCI in a population of kidney transplantation recipients.
Patients and Methods: We randomized tested 133 anti HCV and serum HCV- RNA negative adult patients for the presence of OCI. All patients have al least one year of outcome from ingraft. HCV- RNA was tested by real-time RT- PCR in peripheral blood mononuclear cells and in 2 ml of plasma after ultracentrifugation.
Results: Occult HCV infection was positive in 20 patients (15%). Blood transfusions before kidney transplant was more frequent in patients with OCI (p<0.05). One year after ingraft, renal function and proteinuria were similar for both groups (plasma creatinine level 1.58 ± 0,48 mg/dL, 0.40 ± 0.62 gr/d, in the OCI positive group and 1,48 ± 0,88 mg/dL and proteinuria 0.30 ± 0.30 gr/d in the OCI negative group; p=0.42 and p=0.5). At the end of the follow-up, renal function tended to decline faster in the OCI positive group (plasma creatinine level 1.95 ± 1.08) and to have more proteinuria (0.86 ± 1.14) than in the OCI negative group (plasma creatinine level 1.78 ± 0.83, and proteinuria 0.63 ±1.41), although it was not statistical significant (p= 0.072, p=0.429).
Conclusions: The prevalence of OCI in recipients of kidney transplantation in our group is 15%, higher than in the general population. Blood transfusion before kidney transplant could be a risk factor for OCI. The presence of OCI could play a negative role in the outcome of kidney transplants, but more patients and longer follow up, are probably need, to make definitive conclusions.