Analysis of the effectiveness of repeated courses of tuberculosis chemotherapy after inefficient courses

The aim : to study the effectiveness of repeated chemotherapy courses after ineffective courses. Materials and methods . A retrospective documentary study of the general population (n=817) of all registered newly diagnosed cases of tuberculosis in the Kaluga region in 2019–2023 was conducted. Two groups of patients were compared: patients with an effective outcome of chemotherapy (group 1, n=560) and patients with an ineffective outcome of chemotherapy, for whom the repeated course was effective (group 2, n=72). Results and discussion . A high risk of registering an ineffective course of chemotherapy and prescribing a repeated course is noted in unemployed patients (52.8% versus 38%, p=0.0158) and homeless persons (11.1% versus 2.9%, p=0.003). Among patients with an ineffective chemotherapy course and a repeated effective one (group 2), bacterial excretion (91.7% versus 49.3%, p<0.001) and lung tissue decay (86.1% versus 37.5%, p<0.001) are significantly more common. At the same time, the presence of MDR and XDR pathogens, as well as the presence of HIV infection, do not have a significant impact on the registration of an ineffective chemotherapy course (p>0.05). Among patients with DS-TB and MDR-TB in the group with an effective chemotherapy course after an ineffective one (Group 2), bacterial excretion lasts longer (3 months versus 1 month and 2 months versus 10 months, respectively, p<0.001), which determines an increase in the duration of treatment (16 months versus 9 months and 36.80±15.75 versus 19.91±3.85 months, p<0.001). Conclusion . The obtained results show that the duration of bacterial excretion has a significant impact on the duration and effective outcome of TB chemotherapy in patients with both DS-TB and MDR-TB.