Effects of secondary infections on the multidrug-resistant Tuberculosis: A cohort study

Tuberculosis (TB) causes over a million deaths annually and is still one of the most important public health problems worldwide. According to the World Health Organization estimates, the highest rates of TB in the European Region are in Tajikistan, Kazakhstan, Moldova, Kyrgyzstan, Romania, and Uzbekistan. The purpose of this study was to investigate the spectrum of nonspecific microorganisms isolated in patients with multidrug-resistant TB in Central Kazakhstan and to assess their susceptibility to antimicrobial drugs.

The patients were divided into 2 groups: group 1 with multidrug-resistant forms of pulmonary TB (n = 107 patients); group 2 with sensitive forms of pulmonary TB (n = 122 patients). Gender, age, and social status of the patients were studied. Microorganisms were identified using the MALDI-TOF method. The statistical significance of different values for binary and nominal parameters was determined using the chi-square test. Changes in binary variables were analyzed using the McNeimer test.

During the study, an expectedly high proportion of tetracycline-resistant pneumococcal strains (66.7% and 60%, respectively) was isolated, which was a consequence of a long-term and practically uncontrolled use of these drugs in Kazakhstan. Fluoroquinolones showed low activity. The results showed that beta-lactam antibacterial drugs maintained their high activity against the causative agents of pneumococcal infection.

It was concluded that secondary microorganisms isolated in patients with multidrug-resistant TB were represented by the strains that were resistant to modern antibacterial drugs. Therefore, for appropriate antibiotic prescription, it is necessary to study materials from the respiratory system in all patients admitted for TB treatment to study the spectrum of nonspecific microorganisms and assess their susceptibility to antimicrobial drugs.