Classifying new anti-tuberculosis drugs: Rationale and future perspectives

The classification of anti-tuberculosis (TB) drugs is important as it helps the clinician to build an appropriate anti-TB regimen for multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB cases that do not fulfil the criteria for the shorter MDR-TB regimen. The World Health Organization (WHO) has recently approved a revision of the classification of new anti-TB drugs based on current evidence on each drug. In the previous WHO guidelines, the choice of drugs was based on efficacy and toxicity in a step-down manner, from group 1 first-line drugs and groups 2-5 second-line drugs, to group 5 drugs with potentially limited efficacy or limited clinical evidence. In the revised WHO classification, exclusively aimed at managing drug-resistant cases, medicines are again listed in hierarchical order from group A to group D. In parallel, a possible future classification is independently proposed. The aim of this viewpoint article is to describe the evolution in WHO TB classification (taking into account an independently proposed new classification) and recent changes in WHO guidance, while commenting on the differences between them. The latest evidence on the ex-group 5 drugs is also discussed

Impact of DOTS expansion on tuberculosis related outcomes and costs in Haiti

BACKGROUND: Implementation of the World Health Organization's DOTS strategy (Directly Observed Treatment Short-course therapy) can result in significant reduction in tuberculosis incidence. We estimated potential costs and benefits of DOTS expansion in Haiti from the government, and societal perspectives. METHODS: Using decision analysis incorporating multiple Markov processes (Markov modelling), we compared expected tuberculosis morbidity, mortality and costs in Haiti with DOTS expansion to reach all of the country, and achieve WHO benchmarks, or if the current situation did not change. Probabilities of tuberculosis related outcomes were derived from the published literature. Government health expenditures, patient and family costs were measured in direct surveys in Haiti and expressed in 2003 US$. RESULTS: Starting in 2003, DOTS expansion in Haiti is anticipated to cost$4.2 million and result in 63,080 fewer tuberculosis cases, 53,120 fewer tuberculosis deaths, and net societal savings of $131 million, over 20 years. Current government spending for tuberculosis is high, relative to the per capita income, and would be only slightly lower with DOTS. Societal savings would begin within 4 years, and would be substantial in all scenarios considered, including higher HIV seroprevalence or drug resistance, unchanged incidence following DOTS expansion, or doubling of initial and ongoing costs for DOTS expansion. CONCLUSION: A modest investment for DOTS expansion in Haiti would provide considerable humanitarian benefit by reducing tuberculosis-related morbidity, mortality and costs for patients and their families. These benefits, together with projected minimal Haitian government savings, argue strongly for donor support for DOTS expansion

Long-term outcomes of the global tuberculosis and COVID-19 co-infection cohort

Background: Longitudinal cohort data of patients with tuberculosis (TB) and coronavirus disease 2019 (COVID-19) are lacking. In our global study, we describe long-term outcomes of patients affected by TB and COVID-19. Methods: We collected data from 174 centres in 31 countries on all patients affected by COVID-19 and TB between 1 March 2020 and 30 September 2022. Patients were followed-up until cure, death or end of cohort time. All patients had TB and COVID-19; for analysis purposes, deaths were attributed to TB, COVID-19 or both. Survival analysis was performed using Cox proportional risk-regression models, and the log-rank test was used to compare survival and mortality attributed to TB, COVID-19 or both. Results: Overall, 788 patients with COVID-19 and TB (active or sequelae) were recruited from 31 countries, and 10.8% (n=85) died during the observation period. Survival was significantly lower among patients whose death was attributed to TB and COVID-19 versus those dying because of either TB or COVID-19 alone (p<0.001). Significant adjusted risk factors for TB mortality were higher age (hazard ratio (HR) 1.05, 95% CI 1.03-1.07), HIV infection (HR 2.29, 95% CI 1.02-5.16) and invasive ventilation (HR 4.28, 95% CI 2.34-7.83). For COVID-19 mortality, the adjusted risks were higher age (HR 1.03, 95% CI 1.02-1.04), male sex (HR 2.21, 95% CI 1.24-3.91), oxygen requirement (HR 7.93, 95% CI 3.44-18.26) and invasive ventilation (HR 2.19, 95% CI 1.36-3.53). Conclusions: In our global cohort, death was the outcome in >10% of patients with TB and COVID-19. A range of demographic and clinical predictors are associated with adverse outcomes

La vieja batalla entre la especie humana y el bacilo de Koch: ¿es posible soñar con erradicar la tuberculosis?

El presente trabajo trata de analizar la complejidad de la vieja batalla que lleva librando, desde hace millones de años, la especie humana contra Mycobacterium tuberculosis, intentando realizar un repaso de todos los conocimientos que se tienen sobre esta enfermedad y de lo más importante de lo que puede acontecer en el futuro, con el fin de llegar a la conclusión de si es posible acabar soñando con erradicar esta enfermedad que tanto daño ha causado a la humanidad. A pesar de que la especie humana tiene suficientes conocimientos para vencer la batalla a M. tuberculosis, importantes condicionantes, sobre todo sociales (pobreza, inmigración, VIH, MDR), están favoreciendo la guerra del lado del bacilo. Y que, incluso aplicando adecuadamente todos los buenos conocimientos adquiridos para el control de la TB (detección y curación de casos, quimioprofilaxis, vacunación BCG, etc.), se tardaría aún varios siglos en poder conseguir la erradicación. Sólo la posibilidad de descubrir una vacuna 100% eficaz, o el descubrimiento de nuevas asociaciones antimicrobianas que pudiesen curar la enfermedad en un plazo no superior a 15 días, podría acelerar este ritmo hacia la erradicación. Pero, lamentablemente, no existen fundamentos que permitan soñar con que cualquiera de estas dos posibilidades pueda cumplirse en los próximos 10-20 años. Por lo tanto, el sueño de erradicar la TB es un sueño muy antiguo, pero, lamentablemente, aún muy lejano