Paediatric cervicofacial lymphadenitis caused by non-tuberculous mycobacteria: nation- wide overview in the period 2000-2020

Abstract

Purpose Cervicofacial lymphadenitis caused by non-tuberculous mycobacteria (NTM) is a rare but increasing infection in children worldwide. The purpose of this study was to analyse and evaluate all microbiologically proven cases of NTM lymphadenitis in children under the age 14 years and to discuss possible reasons why there is no Mycobacterium haemophilum isolates among cases of paediatric NTM lymphadenitis in Slovenia. Methods Between 2000 and 2020, we retrospectively reviewed laboratory and medical records for some basic demographic and microbiological data. Different clinical samples were collected in medical centres and regional hospitals from all over Slovenia. Results In the period before mandatory BCG vaccination was discontinued (2000–2005), we did not observe any case of paediatric NTM lymphadenitis. After discontinuation of non-selective BCG vaccination of new-borns (2006–2020), we identified 55 cases of microbiologically confirmed NTM lymphadenitis in BCG-unvaccinated children with median age 26.0 months (range: 15.0–75.0 months). Mean annual incidence of paediatric NTM lymphadenitis accounted for 1.26 (range: 0.35–2.38) per 100,000 children. The main causative agents were Mycobacterium avium (38/55; 69.1%) and M. intracellulare (9/55; 16.4%). We did not find any M. haemophilum isolate. Since 2006, each year we microbiologically confirm sporadic cases of paediatric NTM lymphadenitis, a condition not diagnosed before. Conclusions Strong evidence suggests that the main reason for that is discontinuation of universal BCG vaccination in March 2005. Nevertheless, we could not neglect the effect of improved diagnostic procedures used in recognizing NTM as causative agents of paediatric lymphadenitis.