Efficacy of the Confidential Unit Exclusion Option in Blood Donors in Tehran, Iran, Determined by Using the Nucleic Acid Testing Method in 2008–2009

Background: In recent years, the confidential unit exclusion (CUE) option has been used to increase blood safety at blood transfusion centers in several countries. The epidemiologic characteristics of diseases and demographic characteristics of patients vary in different countries; therefore, we investigated whether the CUE option is useful in Iran. In this study, we determined the prevalences of hepatitis B virus (HBV) and hepatitis C virus (HCV) in CUE-positive and CUE-negative units, as well as the efficacy of the CUE option. Objectives: The aim of this study was to evaluate the efficacy of the CUE option in reducing the prevalences of HBV and HCV in blood units. Patients and Methods: All donors were tested for the HCV antibody (anti-HCV) and hepatitis B surface antigen (HBsAg). Supplemental tests were performed to confirm the presence of viruses in the units that tested positive. In total, 2000 units (1000 CUE-positive units and 1000 CUE-negative units) were tested using the nucleic acid testing (NAT) method. The prevalence of infectious markers was estimated in all demographic subgroups. Results: The prevalences of HBV and HCV markers were higher in donors who opted for CUE than in those who did not. The CUE option had low sensitivity (21.5%) and positive predictive value (PPV; 20.9%) for the markers. Most of the donors who opted for CUE for the first time were men with low levels of education. Conclusions: The CUE option has low sensitivity and PPV, and its effectiveness in reducing the transmission of infectious diseases through window-period units is minimal. The CUE process can be continued in Iran because Iran is geographically located in a region where HBV is endemic; however, higher levels of education are necessary to make this process effective.