Multicenter feasibility study to assess external quality panels for molecular diagnostics for tuberculosis in China.

The roll-out of molecular diagnostic tools continues to be the most important shift in the tuberculosis diagnostic landscape. The aim of this study was to develop a novel external quality assessment (EQA) panels for molecular TB diagnostics. In addition, we also assessed the performance of the laboratories with the EQA panels in China. Dried Mycobacterium tuberculosis (MTB) DNA in the chelex resin was designed as part of an EQA program. The storage of genomic DNA in the chelex resin layer had no effect on the stability of genomic DNA, even after 12 weeks of storage. Seventy-one laboratories have participated in EQA of molecular diagnostics for TB diagnosis in 2018. GeneXpert (74.6%, 53/71) was the most predominant molecular method, followed by GeneChip (32.3%, 23/71), MeltPro (22.5%, 16/71), and TB-LAMP (7.0%, 5/71). Out of 105 EQA panels, 103 EQA results (98.1%) achieved perfect scores, whereas the other two (1.9%) had satisfactory scores. There were a total of two false-negative results reported from two laboratories with local LAMP, respectively. In conclusion, we firstly develop feasible EQA panels for molecular diagnostics for tuberculosis in China. Our data demonstrate that a majority of participating laboratories are able to produce perfect results with molecular diagnostics in China, giving us important hints for the implementation of molecular diagnostics.