Influence of diabetes mellitus on sputum conversion rate in pulmonary tuberculosis and on antituberculous drug resistance

<b>Background:</b> Diabetes mellitus (DM) has an influence on many aspects of tuberculosis (TB). <b>Objectives:</b> to correlate the influence of diabetes mellitus on sputum conversion rate and antituberculous drug resistance. <b>Methods:</b> The study comprised 194 pulmonary tuberculosis (PTB) patients divided in two groups, i.e. the group of TB associated with DM and the group of patients affected only by TB. Sputum smear and liquid culture (MGIT 960) examination were performed at TB diagnosis and subsequently at completion of the initial phase as well as during the continuation phase of TB treatment. Drug sensitivity test (DST) was also performed for all patients. <b>Results:</b> Sputum conversion rate was 86.9% in diabetic group and 97.7% in non-diabetic group in the end of the initial phase (p&lt;0.05). The average number od days needed for sputum smear conversion after the onset of antituberculous treatment was significantly increased in TB patients with diabetes mellitus compared to those without diabetes (p&lt;0.001). No significant difference was registered in the examined groups according to the DST (96.4% in non-diabetic TB group and 98.6% in diabetic group with TB). Multidrug resistance rate was 1.4% in diabetic group. No multidrug resistance in non-diabetics was registered at all. <b>Conclusion:</b> Diabetes mellitus affected delayed sputum conversion. Multidrug resistant tuberculosis was registered in TB group with diabetes mellitus that is known as more severe and more difficult to be cured. <b>Keywords:</b> pulmonary tuberculosis, diabetes mellitus, sputum conversion rate, multidrug resistant tuberculosis