Implementation of GeneXpert MTB/Rif proficiency testing program: A Case of the Uganda national tuberculosis reference laboratory/supranational reference laboratory

BACKGROUND: Following the WHO's endorsement of GeneXpert MTB/RIF assay for tuberculosis diagnosis in 2010, Uganda's ministry of health introduced the assay in its laboratory network in 2012. However, assessing the quality of the result produced from this technique is one of its major implementation challenges. To bridge this gap, the National tuberculosis reference laboratory (NTRL) introduced the GeneXpert MTB/RIF proficiency testing (PT) Scheme in 2015. METHODS: A descriptive cross-sectional study on the GeneXpert PT scheme in Uganda was conducted between 2015 and 2018. Sets of panels each comprising four 1ml cryovial liquid samples were sent out to enrolled participants at preset testing periods. The laboratories' testing accuracies were assessed by comparing their reported results to the expected and participants' consensus results. Percentage scores were assigned and feedback reports were sent back to laboratories. Follow up of sites with unsatisfactory results was done through "on and off-site support". Concurrently, standardization of standard operating procedures (SOPs) and practices to the requirements of the International Organization for Standardization (ISO) 17043:2010 was pursued. RESULTS: Participants gradually increased during the program from 56 in the pilot study to 148 in Round 4 (2018). Continual participation of a particular laboratory yielded an odd of 2.5 [95% confidence interval (CI), 1.22 to 4.34] times greater for achieving a score of above 80% with each new round it participated. The "on and off-site" support supervision documented improved performance of failing laboratories. Records of GeneXpert MTB/RIF PT were used to achieve accreditation to ISO 17043:2010 in 2018. CONCLUSION: Continued participation in GeneXpert MTB/RIF PT improves testing accuracy of laboratories. Effective implementation of this scheme requires competent human resources, facility and equipment, functional quality management system, and adherence to ISO 17043:2010.