Table 1

Recommended microbiological tests to support a diagnosis of NTM-PD

Tests to detect NTM in respiratory samples12 22
Microscopy (AFB smear)LowModerateLowHighRapid, but variable sensitivity and cannot distinguish NTM from Mycobacterium tuberculosis
Direct molecular detection on primary sampleModerateHighModerateLowNTM-specific: costly and less sensitive than conventional AFB culture. Limited uptake: TB PCR is useful as a rule-out test for NTM on smear-positive samples
Mycobacterial cultureHighHighLowHighMost sensitive method to detect NTM from respiratory samples.
Optimal results require the use of both solid and liquid media. Slow results, taking days to weeks
Tests to speciate and type NTM in respiratory samples12 22
  1. Line probe assays

  2. PCR product restriction analysis

  3. Partial gene sequencing


ModerateHighModerate/highLow/moderateEnables species identification, including subspecies of M. abscessus. May require phenotypical drug sensitivity testing to determine inducible macrolide resistance
WGSHighHighModerate/highLow/moderateImproved discrimination of strains enables WGS to be used to investigate possible person-to-person transmission events
  • AFB, acid-fast bacilli; MALDI-TOF, matrix-assisted laser desorption ionisation-time of flight ; NTM, non-tuberculous mycobacteria; NTM-PD, non-tuberculous mycobacterial pulmonary disease; PCR, polymerase chain reaction; TB, tuberculosis; WGS, whole-genome sequencing.