Mycobacterium chimaera pulmonary infection complicating cystic fibrosis: a case report

Abstract

Background: Mycobacterium chimaera is a recently described species within the Mycobacterium avium complex. Its pathogenicity in respiratory tract infection remains disputed. It has never been isolated during cystic fibrosis respiratory tract infection.

Case presentation: An 11-year-old boy of Asian ethnicity who was born on Réunion Island presented to our hospital with cystic fibrosis after a decline in his respiratory function over the course of seven years. We found that the decline in his respiratory function was correlated with the persistent presence of a Mycobacterium avium complex organism further identified as M. chimaera.

Conclusion: Using sequencing-based methods of identification, we observed that M. chimaera organisms contributed equally to respiratory tract infections in patients with cystic fibrosis when compared with M. avium subsp. hominissuis isolates. We believe that M. chimaera should be regarded as an emerging opportunistic respiratory pathogen in patients with cystic fibrosis, including young children, and that its detection warrants long-lasting appropriate anti-mycobacterial treatment to eradicate it.

Figure 1

Chronological representation of Mycobacterium chimaera respiratory tract infection in a CF patient. Arrows indicate requests for mycobacterial detection in the sputum. Dotted arrows indicate negative culture. Filled arrows indicate positive culture for M. chimaera. + indicates acid-fast bacilli stain seen upon direct microscopic examination of sputum samples. Antibiotic therapy is represented by black squares. Duration of treatment (in weeks) is indicated above the brackets.