High Prevalence of Nontuberculous Mycobacteria in Cystic Fibrosis Patients in Tropical French Reunion Island.

Abstract

Reunion Island is a French overseas department located in a tropical area, where cystic fibrosis incidence is high. Cystic fibrosis (CF) patients are at risk of developing nontuberculous mycobacteria (NTM) infection. Epidemiologic studies are lacking in Reunion Island. From 2002 to 2015, a retrospective review was performed in university hospitals on Reunion Island. All CF patients having at least 1 positive NTM isolate were included. Clinical, radiologic, and microbiologic data were collected from patient records. Fifty-one CF patients were included. The overall estimated prevalence of NTM was 26.4% in total CF population and 36.9% in patients over 12 years of age. Mycobacterium abscessus and Mycobacterium avium were the most frequently identified species found in 31 patients (60.8%) and 14 patients (27.4%), respectively. A rare NTM species: Mycobacterium simiae was found in 4 patients (7.8%). Twenty-nine patients (56.9%) met the American Thoracic Society (ATS) criteria for infection. They were more likely younger with a low body mass index and more frequently infected by Mycobacterium abscessus (22/29). The overall prevalence of NTM in tropical Reunion Island is 3 times higher than in metropolitan France. A different environmental exposure in a tropical climate or risk factors related to cystic fibrosis or its treatment in Reunion patients could explain it.