Nontuberculous Mycobacteria (NTM)

Most patients with NTM pulmonary disease (NTMPD) have bronchiectasis and should also be subject to the components of the bronchiectasis pathway

(Specific to NTM PD: Diagnosis is based on all 3 criteria)
Clinical: compatible symptoms and exclusion of other diagnoses
Microbiologic: At least 2 positive sputum cultures with the same species/subspecies
Radiologic: compatible radiologic abnormalities

Culture with solid and liquid media recommended

Species identification with molecular identification preferred

MAC and M. abscessus most common
M avium complex (MAC)–10 species, most common are M avium and M intracellulare
M abscessus–3 subspecies: M abscessus, M bolletii, M massiliense

MAC–test for macrolide and amikacin susceptibility

M abscessus–test for CLSI recommended antibiotics and inducible macrolide resistance

• Initiation of treatment or “watchful waiting” dependent on benefit-risk assessment
• Goals of care: Culture conversion versus improving symptoms versus slowing progression

• Shared decision making is essential: acceptance, burden of treatment, goals of care

• Early treatment may favor less intense medications and better tolerance

• Risk factors for progression: fibrocavitary (FC) versu nodular bronchiectatic (NB), age, low BMI(<18.5), increased inflammatory markers (CRP, ESR), low albumin, male sex

• Severity factors: FC versus NB disease, multi-lobar, AFB smear positivity, presence of co-morbidities

• Azithromycin, ethambutol, rifampin

• Nodular bronchiectatic: T.I.W. dosing versus fibrocavitary: Q.D. dosing plus T.I.W. IV amikacin

• Refractory defined as remaining sputum culture positive after at least 6 months of guideline-based therapy
• Treatment: Assess adherence to the treatment regimen, obtain repeat drug susceptibility test results, consider determination of serum drug concentrations, add amikacin liposome inhalation (ALIS) suspension to regimen, consider addition of another drug, and consider surgical resection

• Referral: Consider referral to specialized center of NTMPD care

Referral to a specialed center of NTMPD care

IV medications: amikacin, imipenem or cefoxitin, tigecycline

Oral: azithromycin, bedaquiline, clofazimine, linezolid or tedizolid, omadacycline

Macrolide resistant: Initial Phase: 2–3IV drugs, 2–3 oral drugs
Continuation Phase: 2–3 oral drugs

Macrolide susceptible: Initial Phase: 1–2 IV drugs, 2 oral drugs
Continuation Phase: 2–3 oral drugs

• Treatment response: Sputum cultures every 1-2 months, low dose chest CT or other imaging at 3 - 6 months and then every 6–12 months and end of treatment, CRP/ESR if elevated at baseline

• Adverse drug reactions: CBC, CMP at baseline and every 1-3 months, visual acuity and red/green color discrimination at baseline and every 2-3 months, audiogram at baseline and every 2-3 months in people receiving an aminoglycoside, EKG at baseline and every 3-6 months in people receiving a macrolide, clofazimine, or bedaquiline

• Monitoring to be done sooner in event of new symptoms or concerns

Dependent on goals of care, generally 12 months after sputum culture conversion

Consider referral to a specialized center for: refractory MAC, recurrent MAC, macrolide resistant MAC, M abscessus (especially if macrolide resistant), consideration of surgical intervention, development of medication intolerance, uncertain goals of care, refractory co-morbidities.