Pharmacists Optimize Management of Nontuberculous Mycobacterial Infections

Non-tuberculous mycobacteria (NTM) infections are notoriously difficult to treat due to the complexity of their treatment regimens and the varied response to different species of NTM. Clinical pharmacists, with their expertise in medication management and therapeutic drug monitoring (TDM), are well positioned to make a meaningful difference in optimizing treatment strategies and improving patient outcomes. A study conducted by researchers at Mayo Clinic underscores the crucial role of clinical pharmacists in managing NTM infections, highlighting their impact on medication optimization and the identification of drug therapy complications.

Pharmacist displaying global instances of mycobacterium avium complex on a laptop | Image Credit: © Yurii Kibalnik - stock.adobe.com

NTM infections are considered any illness caused by bacteria from the genus mycobacterium except for M. tuberculosis complex or M. leprae, which are responsible for tuberculosis and leprosy, respectively. NTM are naturally occurring and can be found in dust, soil, and water. They typically affect the lungs but can also infiltrate the bones, blood, skin, or lymph nodes through drinking contaminated water, inhaling the bacteria from the environment, and via medical devices or surgical tools, including needles. Symptoms of NTM infection include fever, fatigue, weight loss, and swollen lymph nodes.¹

NTM infections are challenging to treat for a number of reasons. Treatment regimens often require long-term treatment involving multiple antimicrobials, which can be challenging for patients to tolerate and adhere to. NTM medicines also have significant drug interactions, particularly with common antibiotics such as clarithromycin (Biaxin; Abbott Laboratories) and rifampin (Rifadin; Sanofi), which can alter serum concentrations and treatment efficacy. The pathology of NTM infections is another significant challenge for patients and health care providers, such as clinical pharmacists. Different species of NTM can cause various clinical syndromes and may respond differently to treatment.²

The challenges of treating NTM infections necessitate individualized treatment with an interdisciplinary and patient-centered care approach. Clinical pharmacists are well positioned to enhance the care of patients with NTM infections due to their expertise in medication management, TDM, patient collaboration, and collaborative interdisciplinary practice. In a study published in the Journal of Clinical Tuberculosis and Other Mycobacterial Diseases by the researchers, clinical pharmacist involvement in treating patients with NTM infections greatly enhanced patient care through identification of drug therapy complications.²

The study aimed to characterize the involvement and impact of clinical pharmacists in managing patients with NTM infections, focusing on their interventions regarding medication management and TDM. The authors assessed the medical charts of 77 patients (median age 68.5 years; 71.4% female) ages 18 and older who were seen by a clinical pharmacist specializing in NTM from January 1, 2018, through June 1, 2020. These patients had to be adults who received face-to-face consultations with the pharmacist and had at least 2 anti-mycobacterial medications initiated for treatment.²

The clinical pharmacists received referrals primarily from pulmonology physicians (63.6%), followed by infectious diseases clinicians. Various drug therapy problems were identified: 23% of patients required additional therapy, 24.3% had unnecessary therapy, 6.8% needed a different drug, 75.7% were found to be on doses that were too low, and 20.3% were on doses too high. Additionally, 31.1% experienced adverse drug reactions, and 8.1% faced adherence issues.²

TDM was performed in 15 patients, of whom 8 had adjustments to their dosage (53.3%) based on the results. The most common drugs that required modifications included azithromycin (Zithromax; Pfizer) and ethambutol (Myambutol; Epic Pharma LLC). Regarding clinical outcomes, a clinical failure rate of 16.9% was observed, defined as the worsening of symptoms or the need for treatment escalation during follow-up. Among the patients who underwent TDM, 53.3% had their doses changed; however, one of these patients still experienced clinical failure. In contrast, 8 of the 62 patients who did not undergo TDM also experienced clinical failure.²

The results of this study highlight the significant role that clinical pharmacists play in optimizing medication management and utilizing TDM, which may enhance patient outcomes by minimizing drug therapy problems in the treatment of complex infections caused by non-tuberculous mycobacteria.

REFERENCES

1. Nontuberculous mycobacteria infections. Cleveland Clinic. February 19, 2024. Accessed February 25, 2025. https://my.clevelandclinic.org/health/diseases/21200-nontuberculous-mycobacteria-infections

2. Woods A, Mara K, Rivera C. Clinical pharmacists’ interventions and therapeutic drug monitoring in patients with mycobacterial infections. Journal of Clinical Tuberculosis and Other Mycobacterial Diseases. February 2025. Doi:10.1016/j.jctube.2023.100346