Level of Mycobacteria in Pre-treatment Sputum and Susceptibility of M. Tuberculosis Strains Isolated from Patients with Non-multidrug-resistant Pulmonary Tuberculosis AFB (+) and Factors Influencing MGIT Results after the First 8 Weeks of Anti-tuberculosi

Abstract

This study assesses the level of mycobacteria in sputum before treatment, and susceptibility of M. Tuberculosis strains isolated from TB patients with AFB (+) and non-multidrug-resistance to the first-line anti-TB drugs. Factors influencing MGIT outcome after the first 8 weeks of first-line anti-TB drugs therapy in patients with pulmonary tuberculosis were also analyzed. The study performed an analytical observation of 128 patients with non-multidrug-resistance pulmonary tuberculosis AFB (+) for evaluating the level of Mycobacteria in sputum before treatment by smear microscopy method; the susceptibility of M. tuberculosis isolated from sputum of the patient was analyzed by Lowenstein - Jensen method. Factors affecting positive MGIT results after 2 months of treatment were determined by multivariate logistics regression. The study results show that the patients having AFB3+ accounted for 28% of the new cases and 24.5% of the retreatment patients. The percentage of any anti-TB drug resistance in the retreatment tuberculosis was 59.6%, higher than that of the new case TB (23.6%). There was a high rate of M. tuberculosis strains resistant to Streptomycin and Isoniazid (12.5% and 16.8% for the new cases; 42.3% and 36.5% for the retreatment cases, respectively). Large radiographic chest lesions and high AFB levels in pre-treatment sputum were factors associated with a positive MGIT result after the first 8 weeks of treatment. Most of the TB patients had a high level of mycobacteria in sputum samples collected before treatment. The percentage of M. tuberculosis strains isolated from sputum of pulmonary non MDR-TB patients with any anti-TB drug resistance was high. High mycobacteria level in pre-treatment sputum and radiographic chest lesions related to positive MGIT result after the first 8 weeks of treatment.

Keywords

Pulmonary tuberculosis, first-line anti-TB drugs, anti-TB drug resistance, susceptibility, M. tuberculosis.

References

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