Use of drug-susceptibility testing for management of drug-resistant tuberculosis, Thailand, 2004-2008

Abstract

In 2004, routine use of culture and drug-susceptibility testing (DST) was implemented for persons in 5 Thailand provinces with a diagnosis of tuberculosis (TB). To determine if DST results were being used to guide treatment, we conducted a retrospective chart review for patients with rifampin-resistant or multidrug-resistant (MDR) TB during 2004-2008. A total of 208 patients were identified. Median time from clinical sample collection to physician review of DST results was 114 days. Only 5.8% of patients with MDR TB were empirically prescribed an appropriate regimen; an additional 31.3% received an appropriate regimen after DST results were reviewed. Most patients with rifampin -resistant or MDR TB had successful treatment outcomes. Patients with HIV co-infection and patients who were unmarried or had received category II treatment before DST results were reviewed had less successful outcomes. Overall, review of available DST results was delayed, and results were rarely used to improve treatment.

Keywords: MDR TB; TB; Thailand; anti-tuberculosis treatment; bacteria; clinical management; drug resistance; drug susceptibility testing; laboratory testing; multidrug-resistant tuberculosis; rifampin-resistant tuberculosis; treatment management; tuberculosis; tuberculosis and other mycobacteria.

Figure 1

Selection of patients for an analysis of drug-susceptibility testing and management of drug-resistant tuberculosis, Thailand, October 2004–September 2008. Patients had rifampin- or multidrug-resistant tuberculosis and were from 5 Thailand provinces participating in the Thailand Active TB Surveillance Network. TB, tuberculosis; DST, drug-susceptibility testing; MDR, multidrug resistant; RIF, rifampin; Private, patient from private hospital; NGO, patient from nongovernmental hospital; NTM, nontuberculosis mycobacterium.

Figure 2

Percentage of MDR-TB patients who were eligible for a treatment regimen change (n = 131) who received a change, according to time from the first review of DST result by the physician, TB Active Surveillance Network, Thailand 2004–2008. Rx, prescription treatment. DST, drug-susceptibility testing; MDR, multidrug-resistant TB.