Baseline Radiographic and Microbiologic Markers Predict Treatment Outcomes in Lesotho MDR-TB Cohort
As detailed in a study of adults undergoing a shortened all-oral regimen for multidrug- or rifampicin-resistant tuberculosis in Lesotho, researchers have identified specific baseline radiographic and microbiologic features that correlate with treatment outcomes.
Clinical Characteristics of the Lesotho Prospective Cohort Study
The prospective cohort study, registered under NCT05871489, followed 238 participants with bacteriologically confirmed pulmonary MDR/RR-TB. The cohort had a median age of 41, with an interquartile range spanning 31 to 56 years. Among the participants, 29 percent were female and 62 percent were living with HIV.
Researchers evaluated baseline microbiologic and radiographic features to measure their associations with time-to-culture-conversion, end-of-treatment outcomes, and final post-treatment outcomes. Out of 148 participants who had positive baseline cultures and evaluable data, 142 experienced conversion within four months, representing a 95.9 percent conversion rate.
Differential Impacts of Baseline Features Across HIV Status
Unfavorable final outcomes across the cohort totaled 27, encompassing 20 deaths, three treatment failures, and four recurrences. Specific lung pathologies showed distinct associations with these outcomes depending on the patient’s HIV status.
Bilateral disease demonstrated a stronger association with unfavorable outcomes in participants without HIV. Conversely, lung fibrosis and high sputum smear grade showed stronger associations with unfavorable outcomes among participants living with HIV.
Fibrosis, cavitation, bilateral disease, and high smear grade were collectively associated with delayed culture conversion and lower odds of overall treatment success.
Severe Fibrocavitary Disease and Final Treatment Success
Specific combinations of baseline damage heavily influenced final therapeutic success. Cavitation paired with a high smear grade showed a negative association with favorable final outcomes, yielding an unadjusted odds ratio of 0.29 with a 95 percent confidence interval from 0.11 to 0.78, and an adjusted odds ratio of 0.39 with a confidence interval from 0.14 to 1.14.
Severe fibrocavitary disease, defined in the study as multi-lobar fibrosis combined with at least one cavity measuring 5 cm or greater, demonstrated an even stronger negative association with favorable final outcomes. This classification returned an unadjusted odds ratio of 0.20 with a 95 percent confidence interval from 0.07 to 0.64, and an adjusted odds ratio of 0.26 with a confidence interval from 0.07 to 0.94.
These findings indicate that evaluating baseline sputum and chest radiographic features in combination can help clinicians identify higher-risk patients. Such stratification may inform risk-adapted clinical strategies for patients receiving shortened all-oral MDR/RR-TB regimens.
