A combined effort of 11 laboratories in the WHO African region to improve quality of Buruli ulcer PCR diagnosis: The "BU-LABNET".

Buruli ulcer is one of the 20 neglected tropical diseases in the world. This necrotizing hypodermitis is a chronic debilitating disease caused by an environmental Mycobacterium ulcerans. At least 33 countries with tropical, subtropical and temperate climates have reported Buruli ulcer in African countries, South America and Western Pacific regions. Majority of cases are spread across West and Central Africa. The mode of transmission is unclear, hindering the implementation of adequate prevention for the population. Currently, early diagnosis and treatment are crucial to minimizing morbidity, costs and preventing long-term disability. Biological confirmation of clinical diagnosis of Buruli ulcer is essential before starting chemotherapy. Indeed, differential diagnosis are numerous and Buruli ulcer has varying clinical presentations. Up to now, the gold standard biological confirmation is the quantitative PCR, targeting the insertion sequence IS2404 of M. ulcerans performed on cutaneous samples. Due to the low PCR confirmation rate in endemic African countries (under 30% in 2018) for numerous identified reasons within this article, 11 laboratories decided to combine their efforts to create the network "BU-LABNET" in 2019. The first step of the network was to harmonize the procedures and ship specific reagents to each laboratory. With this system in place, implementation of these procedures for testing and follow-up was easy and the laboratories were able to carry out their first quality control with a very high success rate. It is now time to integrate other neglected tropical diseases to this platform, such as yaws or leprosy.

Prevalence of Multi-Drug Resistant Tuberculosis among Tuberculosis Patients Attending Chest Clinics in Osun-State, Nigeria.

BACKGROUND: The development of multidrug-resistant tuberculosis (MDR-TB) poses a considerable threat to tuberculosis control programmes in Nigeria. There is an increase in the prevalence of MDR-TB worldwide both among new tuberculosis cases as well as previously-treated ones. There is also a rise in transmission of resistant strains due to an increase in MDR-TB patients largely due to the poor drug compliance and the impact of Human immunodeficiency virus infection. Therefore, we intend to determine the extent of MDR-TB among attendees of chest clinics in Osun-State, Nigeria. OBJECTIVES: The objective of this study was to determine the prevalence of MDR-TB among confirmed tuberculosis patients attending chest clinics in Osun-State, Nigeria. METHODS: This study was conducted among 207 attendees of chest clinics in Osun-State between June, 2015 and October 15, 2016. Sputum and blood samples of the participants were collected. GeneXpert test was carried out first on the samples for simultaneous identification of MTB and rifampicin resistance. Sputum samples were cultured on Lowenstein-Jensen (L-J) medium using N-acetyl-Lcysteine- sodium hydroxide (NALC-NaOH) decontamination method. Drug susceptibility testing (DST) to three first-line drugs was carried out using the proportion DST method. RESULTS: The prevalence of MTB was found to be 27.5% while the prevalence of MDR-TB from the fifty-seven isolates was 10.5%. Previously treated and new cases had a prevalence of 7.0% and 3.5% MDR-TB, respectively. Seventy (33.8%) participants were positive for HIV infection, out of which twenty-six (12.6%) had co-infection of tuberculosis and HIV. The mono-resistance rates of the three first-line drugs used were: 5.3% and 8.7% for ethambutol (EMB) and isoniazid (INH), respectively. No isolate had mono-resistance (0%) to rifampicin (RIF). CONCLUSION: This study observed the prevalence of 27.5% MTB and a prevalence of 10.5% MDR-TB among the MTB isolates. The prevalence of TB is high in Osun State. MDR-TB prevalence is higher compared with the national estimate of MDR-TB (5.1%) of 2017. Resistant TB is a threat to national tuberculosis control and it is recommended that all the facilities be equipped to cater to its diagnosis.