Clinical features and incidence of Mycobacterium avium infections in children

Mycobacterium avium is the most common pathogen in children presenting as non-tuberculous mycobacterial lymphadenitis. In Sweden non-tuberculous mycobacterial infection is a notifiable disease. The goal of our study was to determine the annual incidence of M. avium infection in Swedish children, 1998-2003, and describe clinical features related to age and treatment of children with M. avium lymphadenitis. To do this, we retrospectively analysed patient records of 162 children less than 7 y of age from the entire country with culture-verified M. avium disease. The incidence of M. avium infection in Sweden was lower in 2000-2003 than in 1998-1999. Young children (≤24 months old) had more constitutional symptoms at onset of disease than older children. One-third of the children had received 2 or more antibiotic courses before diagnosis. Disfiguring scars after healing were more common in children who were not treated with surgical extirpation of the affected lymph nodes. The decreasing incidence of M. avium infection among Swedish children in recent y is in contrast to reports of increasing non-tuberculous mycobacterial disease from other countries. Our results support the view that M. avium lymphadenitis should be treated by surgical removal of the affected tissue.