Clinical features of XDR-TB patients

<b>Background:</b> Understanding the clinical features of XDR-TB makes it possible to identify its predictors and organize the treatment of these patients. <b>Methods:</b> analyzed and compared records of patients with XDR-TB (708), MDR-TB, excludes XDR-TB (3469) and drug-sensitive TB (4320) by registration group, age, gender, presence of HIV, proportion of rural population, frequency of bacterial excretion by smear microscopy. <b>Results:</b> In the XDR-TB group, patients prevailed after treatment failure (67.5% compared to 48.9% in the MDR-TB group and 5.6% in the drug-sensitive TB group; p&lt;0,01). The proportion of previous treatment default was 6.2% for XDR-TB, 5.2% for MDR-TB (p&gt; 0.05), 1.9% for drug-susceptible TB. The median age in all groups was the same (39 years). The proportion of females was highest among new XDR-TB cases (37.9% compared with 28.9% for MDR-TB and 28.1% for drug-sensitive TB; p &lt;0.05). The proportion of HIV co-infection in the XDR-TB group (15.8%) was lower than in the MDR-TB group (19.7%; p &lt;0.01) but did not differ from that for drug-sensitive TB (16, 3%; p&gt; 0.05). The proportion of rural residents in the XDR-TB, MDR-TB and drug-sensitive TB groups did not differ (31.0%, 28.5% and 31.1%, respectively; p&gt; 0.05). The positive smear rate for XDR-TB was 64.7%, compared with 57.5% for MDR-TB and 56.8% for drug-sensitive TB, respectively, p &lt;0.001. <b>Conclusion:</b> Failure of prior treatment is the greatest predictor of XDR-TB. The default of previous treatment does not increase the frequency of XDR-TB compared with MDR-TB. No impact on the risk of XDR-TB HIV infection, age and rural residence has been identified. The highest epidemic danger of XDR-TB patients is noted.