More Than a Decade of GeneXpert^® <i>Mycobacterium tuberculosis</i>/Rifampicin (Ultra) Testing in South Africa: Laboratory Insights from Twenty-Three Million Tests

Abstract

This study seeks to describe the rollout and current state of South Africa’s GeneXpert molecular diagnostic program for tuberculosis (TB). Xpert MTB/RIF was introduced in 2011 with a subsequent expansion to include extra-pulmonary and paediatric testing, followed by Xpert MTB/RIF Ultra in 2017. Through a centralised laboratory information system and the use of a standardised platform for more than a decade, over 23 million tests were analysed, describing the numbers tested, Mycobacterium tuberculosis complex detection, rifampin resistance, and the unsuccessful test rates. The stratification by province, specimen type, age, and sex identified significant heterogeneity across the program and highlighted testing gaps for men, low detection yield for paediatric pulmonary TB, and the effects of inadequate specimen quality on the detection rate. The insights gained from these data can aid in the monitoring of interventions in support of the national TB program beyond laboratory operational aspects.

Keywords

• GeneXpert MTB/RIF
• GeneXpert MTB/RIF Ultra
• molecular diagnostics
• tuberculosis
• pulmonary tuberculosis
• extra-pulmonary tuberculosis