The role of drug susceptibility testing in M/XDR-TB. Too little and too late - Are we doing the right things?

Antibiotic resistance acquisition versus primary transmission in the presentation of extensively drug-resistant tuberculosis

Mycobacterium tuberculosis is the leading cause of mortality worldwide due to a single bacterial pathogen. Of concern is the negative impact that the COVID-19 pandemic has had on the control of tuberculosis (TB) including drug-resistant forms of the disease. Antimicrobial resistance increases the likelihood of worsened outcomes in TB patients including treatment failure and death. Multidrug-resistant (MDR) strains, resistant to first-line drugs isoniazid and rifampin, and extensively drug-resistant (XDR) strains with further resistance to second-line drugs (SLD), threaten control programs designed to lower TB incidence and end the disease as a public health challenge by 2030, in accordance with UN Sustainable Development Goals. Tackling TB requires an understanding of the pathways through which drug resistance emerges. Here, the roles of acquired resistance mutation, and primary transmission, are examined with regard to XDR-TB. It is apparent that XDR-TB can emerge from MDR-TB through a small number of additional resistance mutations that occur in patients undergoing drug treatment. Rapid detection of resistance, to first-line drugs and SLD, at the initiation of and during treatment, and prompt adjustment of regimens are required to ensure treatment success in these patients. Primary transmission is predicted to make an increasing contribution to the XDR-TB caseload in the future. Much work is required to improve the implementation of the World Health Organization-recommended infection control practices and block onward transmission of XDR-TB patients to contacts including health-care workers. Finally, limiting background resistance to fluoroquinolones in pre-XDR strains of M. tuberculosis will necessitate better antimicrobial stewardship in the broader use of this drug class.

Programmatic challenges in managing multidrug-resistant tuberculosis in Malawi

Background

Multidrug-resistant tuberculosis (MDR-TB) is one of the most urgent challenges that Malawi tends to take a firm public health action. A recent increase in multidrug MDR-TB cases, a decrease in treatment success rate, and a double increase of lost-to-follow-up call into question the country's programmatic management of MDR-TB (PMDT). As such, the study aimed at exploring programmatic challenges in managing MDR-TB in Malawi.

Methods

A comprehensive and nonsystematic search was made in PubMed and Google Scholar using mainly the keywords "MDR-TB" "extensively drug-resistant TB," Malawi. The study reviewed existing guidelines and gray literature and reviewed data obtained from the national TB program (NTP) as well.

Results

The study found the following challenges affecting PMDT: decrease in funding, partial access to GeneXpert, delay in diagnosis, long treatment duration, lack of adequate personal protective equipment, the long turnaround time of culture results, failure to initiate all diagnosed patients on treatment, absence of alternative second-line medicines, and lack of transport from health facilities to patient homes.

Conclusion

If the Malawi NTP is to achieve a vision of a "TB-free Malawi," rigorous efforts at all levels must be made, including mobilizing domestic resources for improved MDR-TB program performance. Developing partners should continue providing the much-needed funding to the Malawi government to stand in the wake of the MDR-TB crisis.

Epidemiology of multidrug-resistant, extensively drug resistant, and totally drug resistant tuberculosis in Middle East countries

The 2015 represent the deadline for the global tuberculosis (TB) targets set through the Millennium Development Goals (MDG). From 2016 and onward, new goals were set to end the global TB epidemic via implementing new campaign entitled "the End TB Strategy". The major hurdle to end TB epidemic in several parts of the world is the emergence and spread of drug resistant Mycobacterium tuberculosis (MTB) strains. The better understanding of the actual global burden of drug resistant tuberculosis would feed into better implementing the End TB Strategy. In this article we summarize the current knowledge on the patterns of drug resistance tuberculosis cases in the Middle East countries. These countries are served by the Eastern Mediterranean Regional Office (EMRO), one out of six regional offices of World Health Organization. Middle East countries are characterized by geographic vicinity and population's interaction. However, they are dissimilar in several aspects such as economy and health infrastructures. Regarding economy, countries in this region are ranging from wealthy to very poor. Prevalence of tuberculosis and patterns drug resistance tuberculosis cases are also following variable trends within countries of this region. In almost all Middle East countries, there is under-reporting of drug-resistance tuberculosis cases. There are shortages in the infrastructures and facilities for detecting the pattern of drug-resistance tuberculosis. For instance, sixout of 14 countries have neither in-country capacity nor a linkage with a partner laboratory for second-line drug susceptibility testing and only 4 countries have registered site performing Xpert MTB/RIF.