Nontuberculous Mycobacteria in Children: A Focus on Bloodstream Infections

Abstract

Background: Nontuberculous mycobacteria (NTM) are ubiquitous organisms with variable disease-causing potential. Bloodstream infections caused by NTM in children are poorly described.

Methods: We describe a retrospective case series of children with culture-confirmed mycobacterial disease managed at the Children's Hospital at Westmead between July 2005 and June 2015.

Results: Sixty-five patients had 149 positive NTM cultures; 55 (83.0%) episodes in 54 patients were considered clinically significant. Of the 54 children who met criteria for NTM disease, 25 (46.3%) had lymphadenitis, 13 (24.1%) lung disease, 8 (14.8%) had soft tissue infection or osteomyelitis and 8 (14.8%) had bacteremia. All children with bacteremia had a central venous catheter; those with pulmonary infection had underlying lung disease and all children with soft tissue infection or osteomyelitis had a history of recent penetrating injury. Disease caused by Mycobacterium avium-intracellulare complex was most common, accounting for 19 (76.0%) and 7 (53.8%) lymph node and lung infections, respectively. The most frequently isolated rapid growing mycobacteria were Mycobacterium fortuitum (8; 15%) and Mycobacterium abscessus (6; 11%), with M. fortuitum accounting for the majority (6; 75%) of bloodstream infections. Six (75%) patients with bacteremia had their intravenous catheter removed and all had a favorable outcome. A single disease relapse was reported in 1 of 2 patients with a retained catheter.

Conclusion: Lymphadenitis was the most common NTM disease manifestation and not associated with comorbidity. NTM bacteremia was always associated with a central line and catheter removal with cure. We were unable to assess the added value of various antibiotic regimens.