Abstract:

Objective To analyze the treatment outcomes of retreated pulmonary tuberculosis patients (PTB) with isoniazid resistance, rifampicin resistance, and drug sensitive PTB patients, and explore the prognosis of patients with isoniazid resistance. Methods From July 2009 to July 2019, a retrospective investigation was adopted to select 922 retreated bacteriologically positive PTB patients with complete data and treatment outcomes from Beijing Chest Hospital of Capital Medical University and other more than 20 domestic tuberculosis prevention and control institutions. Two hundred and nineteen MDR or XDR cases, and 100 non-rifampicin and non-isoniazid resistance cases were excluded, a total of 603 retreated bacteriologically positive PTB patients were enrolled in this study. The standard retreatment regimen was used for the sensitive and not drug-resistant group while an individualized treatment regimen was used for the isoniazid-resistant or rifampicin-resistant group. The treatment outcomes were compared among 485 patients in “drug-sensitive group”, 73 patients in “isoniazid-resistant group” (including isoniazid mono-drug resistance and poly-drug resistance), and 45 patients in “rifampicin-resistant group” (including rifampicin mono-drug resistance and poly-drug resistance). Results At the end of 2nd month’s treatment, the sputum smear negative conversion rate (63.6%, 42/66) and sputum culture negative conversion rate (63.6%, 35/55) in isoniazid-resistant group were lower than those in rifampicin-resistant group (84.6%, 33/39; 70.6%, 24/34) and drug-sensitive group (84.2%, 388/461; 80.0%, 343429) (χ²=16.567, 8.500; P<0.001, 0.014), respectively. At the end of 6th month’s treatment, the sputum smear negative conversion rate (79.7%, 47/59) and sputum culture negative conversion rate (76.5%, 39/51) in isoniazid-resistant group were lower than those in rifampicin-resistant group (89.2%, 33/37 and 93.5%, 29/31) and drug-sensitive group (91.5%, 398/435 and 90.8%, 367/404) (χ²=8.127, 10.533; P=0.017, 0.005), respectively. The cure rate of isoniazid-resistant group (53.4%, 39/73) was lower than that of rifampicin-resistant group (60.0%, 27/45) and drug-sensitive group (69.5%, 337/485) (χ²=8.407, P=0.015); the treatment success rate of isoniazid-resistant group (64.4%, 47/73) was lower than that of rifampicin-resistant group (75.6%, 34/45) and drug-sensitive group (82.1%, 398/485) (χ²=12.587, P=0.002). Conclusion The negative conversion rates and success rates of treatment in retreated PTB patients with isoniazid resistance were lower than that of rifampicin-resistant group and drug-sensitive group. It is suggested that attention should be paid to the drug resistance of every bactericide, especially for those medicines clinically used for a long period.

Key words: Tuberculosis, pulmonary, Retreatment, Tuberculosis, multidrug-resistant, Isoniazid, Rifampin