Author Interviews, Global Health, Infections, NEJM / 21.09.2016
Cures of Multidrug Resistant Tuberculosis Probably Underestimated Under Current WHO Guidelines
MedicalResearch.com Interview with:
Dr. Heinke Kunst, M.D.
Queen Mary University Hospital, London, United Kingdom
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Multidrug resistant tuberculosis (MDR-TB) has been on the increase worldwide over the past decade. Many patients who have been identified with MDR-TB live in the European region. Despite treatment with expensive second-line drug regimens, curing MDR TB remains a challenge and cure rates were thought to be very low. As part of the EU Commission funded TB-PANNET project 380 patients with MDR-TB were observed at 23 TB centers in countries of high, intermediate and low TB burden in Europe over a period of 5 years. Observation started from the time of diagnosis and lasted until one year after the end of the treatment.
The TBNET proposed new definitions for “cure” and “failure” of MDR-TB treatment based on the sputum culture status at 6 month after the initiation of therapy and whether patients were free from disease recurrence one year after the end of therapy. The researchers found that the WHO criterion for “cure” could not be applied in the majority of patients, simply because most patients who were being treated successfully were not able to produce sputum after 8 months of therapy. The TB-PANNET study showed much higher cure rates using a new definition of cure and failure of treatment for MDR TB in the European region. (61% cure rates compared to only 31% when using WHO criteria.)
The study also demonstrates that the results for “cure” from MDR-TB correlate very well with the level of drug resistance and the time to culture conversion that means the time when TB bacilli are no longer detectable in sputum. The new definitions are also independent of the total duration of treatment and can be applied to the standard 20 months MDR-TB regimen as well as to the 9-12 months shorter course MDR-TB treatment that was recently proposed by the WHO.
(more…)