Objective: To evaluate the working quality of Henan province reference laboratory(PRL) in the surveillance of drug resistance (DRS) in Henan.
Method: West Pacific Regional (WPR) Supranation Reference Laboratory(SRL) in South Korea conducted three times of quality control of drug susceptibility testing (DST) from SRL to PRL and to national reference laboratories(NRLs) in the region at the same time, and once of which from PRL to SRL. The exchanging strains of M. tuberculosis, which were clinical isolated ones containing both drug susceptible and drug resistant cultures, were tested for resistance to SM, INH, RFP and EMB. The DST procedure was proportion method, and L-J medium was used.
Result: It was shown that the sensitivities for most of the four drugs in the three times of DST quality control from SRL to PRL were higher than their specificities, and that the sensitivities for both INH and RFP were 100%. And the accuracy, or agreement, for both INH and RFP was more than 90%, except for that of RFP in the first time. Compared with the results from SRL to NRLs (including Henan PRL), except for the specificity for SM in WPR being higher than that in Henan (84% versus 70%, P < 0.05), there was no significant difference between Henan and WPR on the specificity and sensitivity of the other drugs. Similar characteristics can be found in the results from PRL to SRL. And the efficiency for SM, INH and RFP was all higher than 90%.
Conclusion: The quality control on Henan PRL meet the requirement of the WHO/IUATLD guidelines for surveillance of drug resistance in tuberculosis(1997).