Molecular diagnostics, shorter treatment periods, and socioeconomic incentives can cure a high proportion of multidrug-resistant tuberculosis cases in conflict-affected communities, a new study reveals.

A new molecular diagnostic tool called Xpert MTB/RIF can detect multidrug-resistant TB in less than two hours.

New approaches to the treatment of multidrug-resistant tuberculosis (MDR-TB) in the conflict-affected region of the Democratic Republic of Congo have proved successful. The findings of a large, long-term study in the Democratic Republic of Congo (DRC) led by the University of

Pittsburgh Graduate School of Public Health and Stellenbosch University, in collaboration with the DRC National Tuberculosis Program could guide clinicians and public health workers in other post-conflict or low-income countries battling or at-risk for TB outbreaks.

“Conventional treatment regimens for MDR-TB can be as much as 1000 times more expensive and take four times as long as treatment for regular TB,” said senior study author, Professor Jean Nachega (associate professor in the departments of Epidemiology and Infectious Diseases and Microbiology at Pitt Public Health, and director of the Centre for Infectious Diseases at Stellenbosch University).

“The cure rate is only about 50%, and treatment can have severe side effects, such as permanent hearing loss. Without effective therapy, people with multidrug-resistant TB can infect others who have never had TB before.”

Prof Nachega partnered with lead study author Dr André Bulabula (a doctoral student in Stellenbosch’s Department of Global Health and member of the Infection Control Africa Network), as well as colleagues from the DRC National TB Program, to evaluate 16 448 patients for TB between 2012 and 2017 in post-conflict DRC.

They used a new molecular diagnostic tool called Xpert MTB/RIF to detect multidrug-resistant TB in less than two hours, something that can take several weeks using conventional tests. The scientists found TB in 1 535 patients, and 170 (11%) of them had a strain of TB resistant to the antibiotic rifampicin.

Patients with rifampicin-resistant TB were assigned to either receive a new nine-month regimen, which involved receiving four different antibiotics throughout, supplemented by three other antibiotics (including one injectable) during a four-month intensive phase, or the conventional

20- or 24-month treatment regimens, which involved five different antibiotics taken throughout, supplemented by one injectable antibiotic during a six-month intensive phase.

All the patients were assigned to ‘directly observed therapy’, where a nurse at the local clinic, or a community health worker, or trained family member at home observed the patient take their medication. Of the patients who received the nine-month schedule, 83% were cured, compared to 74% of those receiving conventional therapy.

The biggest predictors of success were the consistent use of directly observed therapy, the lack of serious drug side effects that can cause a patient to stop therapy, and the patient receiving cash incentives for adherence to treatment. “In this challenging treatment setting, it is compelling that our findings are in line with those previously reported by observational studies in Bangladesh and other sub-Saharan African countries, as well as the interim results of an ongoing multinational randomised trial,” said study co-author Professor Zacharie Kashongwe (professor of pulmonology at the University of Kinshasa in the DRC).

Prof Nachega added that the data should inform new MDR-TB care guidelines in low- and middle-income countries, including expanding use of the Xpert testing; prompt initiation of shorter, less-toxic drug regimens that are ideally entirely taken orally; involving trained community health workers in delivering TB services; and developing, as well as initiating, community-based drug-resistant TB prevention strategies.