Objectives: A high prevalence of chronic hepatitis B has been previously reported in heart transplant recipients in our center. Nosocomial transmission of hepatitis B has been therefore suggested. The aim of the present study was to investigate an outbreak of hepatitis B infection in heart transplant recipients and to to look for nosocomial acquisition of hepatitis B in these patients.
Methods: In a retrospective case-control study, review of transvenous endomyocardial biopsy (TEB) procedure, line probe assay and DNA sequencing for characterization of the outbreak isolate genotypes were performed in order to assess the possible risk of nosocomial transmission of hepatitis B in the setting of heart transplantation. Case was defined as a patient negative for HBsAg before heart transplantation and positive after. Controls were matched with cases by date of transplantation and time-interval of HBV infection occurrence in the cases patients.
Results: Transmission of HBV was associated with the number of HBsAg positive patients undergoing TEB the same day and in the same ward (OR=1.17, per additional encounter; 95%CI=1.01-1.37, P=0.02) and with the total number of TEB undergone after a HBsAg positive patient (OR=1.43 for additional encounter, 95%CI=0.97-2.1, P=0.056) but not with the number of biopsies. The virological study identified eight different strains. No common devices nor gloves, drapes, or medical solution were shared among patients during TEB. One staff member, but no surgeon, was HBsAg positive. No further case occurred after implementation of control measures.
Conclusions: Patient-to-patient transmission during TEB sessions was demonstrated by the virological and the case-control studies. This transmission occurred without evidence of blood contact through vials or devices. There is strong evidence that this transmission may be due to the spread of infective blood droplets on the environmental surfaces and the material during the TEB procedure.