University of Pennsylvania researchers report that the hepatitis C infection may largely account for the relatively high number of kidney transplant recipients taking the immunosuppressive drug tacrolimus (Prograf) who subsequently develop diabetes.

The researchers reported that while kidney transplant recipients who did not have hepatitis C had about the same risk of diabetes whether they were taking tacrolimus or the other leading immunosuppressive cyclosporine, those with hepatitis C were almost eight times more likely to develop diabetes on tacrolimus than on cyclosporine.

The researchers reported in the Journal of the American Society of Nephrology that among the hepatitis C positive patients in their study, post-transplant diabetes developed in 57.8 percent of those using tacrolimus for immunosuppression compared to 7.7 percent of those using cyclosporine.

They reported that among kidney transplant recipients who were not hepatitis C positive, post-transplant diabetes developed in 10 percent of those on tacrolimus compared to 9.4 percent of those on cyclosporine.

"HCV is strongly associated with PTDM (post-transplant diabetes mellitus) in renal transplant recipients and appears to account for the increased diabetogenicity observed with tacrolimus," the researchers concluded.

Other sources: Journal of the American Society of Nephrology