P46

Nontuberculous Mycobacteria (NTM) are a diverse group of mycobacteria, ubiquitous in the environment, and only a few species are able to cause infections in humans. Nevertheless, NTM disease cases are increasing globally posing a serious health threat since the majority of NTM species are resistant to common antibiotics. Using a country representative NTM collection centralized in the National Reference Tuberculosis Laboratory (NRL-TB) of the Portuguese National Institute of Health (INSA), we characterized the circulation trends of NTM species in Portugal.

Here, we describe a nationwide retrospective study where all individuals with positive NTM cultures from 2014 to 2020 were included. Isolates were identified using GenoType Mycobacterium CM/AS® (Hain Lifescience), or hsp65 DNA sequencing. Case classification of the disease was based on microbiological data. During this period, the NRL-TB isolated 1118 NTM positive cultures from 944 individuals. Mycobacterium avium complex (MAC) (40,8%), Mycobacterium abscessus-chelonae complex (MABC) (9,6%) and Mycobacterium fortuitum (6,3%) were the species responsible for most of the infections. Median patient age was 64.1±15.9 years and men were the most affected. Lisbon Metropolitan Area (LMA) (31,9%) was the region with the majority of the cases. MAC was more frequent in the North region (38.4%) while MABC and M. fortuitum were predominant in LMA. We were able to identify 172 cases as “definite” or “possible” NTM disease.

As the number of NTM cases was independent of the demography of the region, we highlight the need for a systematic approach to diagnose and report NTM cases to assess its real epidemiology.