The effectiveness of individualized treatment regimen on smear-positive retreatment pulmonary tuberculosis with mono- and poly-drug resistance

Abstract

Objective: To analyze and evaluate the effectiveness of individualized treatment regimen in the therapy of smear-positive retreatment pulmonary tuberculosis with mono-and poly-drug resistance, and therefor to provide information on how to develop rational individualized regimen for retreatment tuberculosis cases with drug resistance. Methods: This was a multi-centered, prospective cohort study. Totally 254 cases of sputum positive tuberculosis with previous treatment history during the period from July 1, 2009 to August 30, 2016 were included in the analysis. All the cases were randomly divided into 3 groups and received therapy after randomization into treatment groups. After 3 months, cases with multidrug resistant tuberculosis, extensively drug-resistant tuberculosis, non-tuberculosis mycobacterial infection and those with smear-positive but culture-negative tuberculosis were excluded according to result of sputum culture and drug susceptibility test (DST). In treatment group A (individualized treatment group), 86 cases with an average age of (42.1±13.7) years for men and (38.5±12.8) years for women, were treated with individualized regimen, which allowed drug replacement on the basis of standard regimen (2SHRZE/6HRE) according to DST result. Treatment duration was recalculated after drug replacement and the total length should be 12 months or more. If the DST result did not show drug resistance, the patients would continue the 8 months' standard treatment. In treatment group B (intensified retreatment regimen group), 86 cases with an average age of (43.2±14.2) years for man and (37.9±14.1) years for women, received intensified retreatment regimen (2HL(2)EZS/2HL(2)EZS(3)/4HL(2)E). The dose for H was 0.3 g/d for patients with body weight <50 kg, and 0.4~0.5 g/d for higher body weight (≥50 kg); The doses for L(2,)E and Z were 0.6 g, 2/w; 0.75, 1/d and 0.5g, 3/d. In treatment group C (standard treatment group), 82 cases with an average of (42.5±11.9) years for man and (38.6±12.8) years for women, were treated with standardized regimen recommended by national tuberculosis program (2HREZS/6HRE). In both group B and C, the total treatment duration was 8 months and the drugs were not replaced for mono-and poly-drug resistance. Treatment outcomes of the 3 groups were analyzed, the status of drug replacement in group A was analyzed, and the adjustment of dose of H and R according to patients' body weight was observed. SPSS 19.0 was used for data analysis. Results: The treatment cure rates for group A, B and C were 73.3%(63/86), 76.7%(66/86) and 50%(41/82), and the treatment success rates were 80.2%(69/86), 84.9%(73/86) and 62.2%(51/82) respectively. Treatment failure was 8.1%(7/86), 4.7%(4/86) and 19.5%(16/82) in 3 groups. There were significant differences in the above indicators for group A and B in comparison with group C(χ(2)=13.127, P=0.001). However, there was no difference observed between group A and B(χ(2)=0.646, P=0.422). In group A, tuberculosis specialized hospitals using regular doses for R was only 38.7%(12/31). After 3 years' follow-up, no-relapse-success for group A was 66.7% (10/15). Conclusions: Inappropriate individualized treatment would increase treatment failure for retreatment tuberculosis. Higher doses of H and R and prolonged extensive therapy phase could contribute to increased treatment success.