Implementation of quality control system for improvement of thalassemia screening at Maung Saung hospital, Roiet province

ABSTRACT

The prevention and control program of thalassemia and hemoglobinopathies has been carried out at Maung Saung Hospital, Roiet province according to the policy of the Ministry of Public Health. Discrepancy between the result of thalassemia screening and confirmatory test is commonly encountered. This study aimed to implement the quality control system at the hospital for improvement of thalassemia and hemoglobinopathies screening using a combined osmotic fragility test (KKU-OF) and dichlorophenolindophenol test (KKU-DCIP-Clear). Study plan was designed and made into 3 phases. In Phase I, a retrospective data in the year 2006 was collected and analyzed to identify to the screening problems. There were 5.4 % false positive and 5.4 % false negative for DCIP test but the effectiveness of OF test could not be determined as α - thalassemia 1 has not been examined. Phase II was an implementation of quality control system for thalassemia screening. Staffs performing screening tests were re-trained at the Centre for Research and Development of Medical Diagnostic Laboratories (CMDL), Khon Kaen University. Standard operating procedures (SOP) for KKU-OF and KKU-DCIP-Clear were then prepared. Phase III was set to evaluate the effectiveness of screening after implementation of the system. Prospective screening was carried out at Maung Saung hospital on 130 subjects and the remaining blood specimens were sent to the CMDL for further confirmatory tests. Among 130 subjects examined,α - thalassemia 1, β - thalassemia and Hb E were identified in 3.9 %, 0.8% and 40.0 %, respectively. The sensitivity, specificity, positive predictive and negative predictive values were found to be 100 %, 95.5 %, 95.0 % and 100 %, respectively. This result indicates that thalassemia and hemoglobinopathies screening at Maung Saung Hospital has been improved which should consequently lead to a more effective prevention and control program.