AUTHOR=Orlando Solon Alberto , Vera Loor Leila Estefania , Calderón Joselyn , Carvajal-Capa Melissa Joseth , Arcos Alcívar Fabrizio , Torres-Lasso Pablo , Maza Valle W. Favián , Vargas González Oliverio N. , Mora-Jaramillo Naomi , León-Sosa Ariana , Rivera Ariana , Rodríguez-Pazmiño Angel Sebastián , Castro-Rodriguez Bernardo , Franco Sotomayor Greta , Uruchima-Campoverde Sandra , Gonzalez Manuel , Benitez-Medina Jose Manuel , Jimenez-Pizarro Natalia , Hermoso de Mendoza Javier , Parra-Vera Henry , Garcia-Bereguiain Miguel Angel 

TITLE=Non-tuberculous mycobacteria and other acid fast bacilli pathogens identification by qPCR and MALDI-ToF MS in tuberculosis-like lesions of slaughtered cattle from Ecuador

JOURNAL=Frontiers in Veterinary Science

VOLUME=Volume 12 - 2025

YEAR=2025

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2025.1565066

DOI=10.3389/fvets.2025.1565066

ISSN=2297-1769

ABSTRACT=IntroductionMycobacterial infections are caused by the Mycobacterium tuberculosis complex (MTBC) but also by non-tuberculous mycobacteria (NTM). While the importance of NTM in opportunistic infections in humans has been gaining attention, surveillance and control programs for cattle health and production remain predominantly focused on bovine tuberculosis (BTB) that it is caused exclusively by MTBC.MethodsIn this study, we conducted a comprehensive inspection of 5,803 cattle carcasses destined for human consumption across 22 abattoirs in five provinces of Ecuador’s coastal region, searching for lesions visually compatible with BTB (BTB-like lesions).ResultsA high prevalence of 13.4% (CI 95%: 12.8–14.6) for BTB-like lesions and 3.1% (CI 95%: 2.6–3.5) for acid-fast bacilli (AFB) presence in lesions was observed. From these lesions, we isolated 48 AFB cultures, 44 of which tested positive for NTM. Strikingly, MTBC was not found in any BTB-like lesion by qPCR. Furthermore, Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-ToF MS) identified six NTM species: M. neoaureum, M. fortuitum, M. novocastrense, M. asiaticum, M. duvalii, and M. mucogenicum. Additionally, other AFB opportunistic pathogenic species were identified, including Tsukamurella paurometabola, Gordonia hongkongensis, and Nocardia spp.DiscussionConsidering the potential misdiagnosis of NTM and other AFB species, BTB surveillance and control programs for MTBC should be revised to consider other opportunistic infections with similar clinical output to BTB.