Epidemiology of infection by pulmonary non-tuberculous mycobacteria in French Guiana 2008-2018

Abstract

Introduction: Unlike diseases caused by Mycobacterium tuberculosis, M. leprae and M. ulcerans, the epidemiology of pulmonary non-tuberculous mycobacteria (PNTM) has not received due attention in French Guiana. The main objective of the current study was to define the incidence of these PNTM infections: NTM pulmonary diseases (NTM-PD) and casual PNTM isolation (responsible of latent infection or simple colonization). The secondary objectives were to determine species diversity and geographic distribution of these atypical mycobacteria.

Methods: A retrospective observational study (2008-2018) of French Guiana patients with at least one PNTM positive respiratory sample in culture was conducted. Patients were then classified into two groups: casual PNTM isolation or pulmonary disease (NTM-PD), according to clinical, radiological and microbiological criteria defined by the American Thoracic Society / Infectious Disease Society of America (ATS / IDSA) in 2007.

Results: 178 patients were included, out of which 147 had casual PNTM isolation and 31 had NTM-PD. Estimated annual incidence rate of respiratory isolates was 6.17 / 100,000 inhabitants per year while that of NTM-PD was 1.07 / 100,000 inhabitants per year. Among the 178 patients, M. avium complex (MAC) was the most frequently isolated pathogen (38%), followed by M. fortuitum then M. abscessus (19% and 6% of cases respectively), the latter two mycobacteria being mainly found in the coastal center region. Concerning NTM-PD, two species were mainly involved: MAC (81%) and M. abscessus (16%).

Discussion/conclusion: This is the first study on the epidemiology of PNTM infections in French Guiana. PNTM's incidence looks similar to other contries and metropolitan France and NTM-PD is mostly due to MAC and M.abscessus. Although French Guiana is the French territory with the highest tuberculosis incidence, NTM should not be overlooked.

Fig 1. Study flow chart.

Fig 2. Incidence of PNTM infections in French Guiana (2008–2018).

Fig 3. Distribution of respiratory isolates of PNTM in French Guiana.

Map was created using BdCarto NGI’s (National Geographic Institute) map database. Base layer of the map: https://geo.data.gouv.fr/fr/datasets/150be61acdce4635daaa8c30fe1f88f088f2e868. Layer created from IGN topo comics (2014). The original data is under Open License 2.0, the description of which is: https://www.etalab.gouv.fr/licence-ouverte-open-licence/.