Nontuberculous Mycobacteria Species in Patients with Concurrent COVID-19 and Mycobacterial Disease

BackgroundThe incidence of nontuberculous mycobacterial (NTM) diseases is increasing globally, with risk factors remaining poorly understood. COVID-19 may alter respiratory tract conditions affecting NTM colonization and infection patterns. ObjectiveTo evaluate species diversity of NTM isolated from patients with NTM-associated diseases with and without a history of COVID-19. MethodsWe analyzed 464 clinical NTM isolates from Russian patients stratified by COVID-19 status (COVID-19+, n=271; COVID-19-, n=193). Diagnosis verification followed ATS/ERS/ESCMID/IDSA Clinical Practice Guidelines. Species identification employed MALDI-TOF mass spectrometry and molecular techniques. Statistical analyses used chi-square and Fishers exact tests with 95% confidence intervals. ResultsSlowly growing species predominated in both groups (97.9% vs 98.2%, p>0.05). COVID-19 was associated with a significant 28% reduction in Mycobacterium avium complex (MAC) prevalence (94.8% vs 66.8%, p<0.05), primarily due to decreased M. avium isolation (80.3% vs 52.0%, p<0.05). Conversely, rare NTM species showed increased prevalence in COVID-19+ patients: M. kansasii complex (0% vs 8.1%, p<0.05), M. terrae complex (0% vs 3.3%, p<0.05), M. simiae complex (0.5% vs 7.0%, p<0.05), and unclassifiable species (2.6% vs 12.9%, p<0.05). ConclusionsCOVID-19 significantly alters the NTM species spectrum in patients with NTM-associated diseases, with reduced MAC prevalence and increased detection of rare NTM species. These findings highlight the importance of species-level identification and may require adaptation of diagnostic and therapeutic approaches in post-COVID patients.