Clinical pharmacists’ interventions and therapeutic drug monitoring in patients with mycobacterial infections

PURPOSE: Infections caused by non-tuberculous mycobacterium (NTM) are increasing, less well-known by health care clinicians, and usually require long term treatment with multiple antimicrobials. There is no existing evidence on clinical pharmacists’ involvement in the care of patients with NTM infections. We sought to characterize pharmacists’ interventions in providing medication management for patients with NTM infections. METHODS: A retrospective review of patients aged 18 years or older seen by a pharmacist specializing in NTM from January 1, 2018 through June 1, 2020 was performed. Charts were reviewed for drug therapy problems identified by a pharmacist. Details regarding therapeutic drug monitoring (TDM) and subsequent dose adjustments were obtained. RESULTS: Seventy-seven patients were included. Median age was 68.5 years, and most patients were female. The most common mycobacterium species treated was Mycobacterium avium/intracellulare complex. Majority of pharmacist consults (63.6%) were referred by Pulmonology physicians, with remainder by Infectious Diseases clinicians. Identified drug therapy problems included: needs additional therapy (23%), unnecessary therapy (24.3%), different drug needed (6.8%), dose too low (75.7%), dose too high (20.3%), adverse drug reaction (31.1%), and adherence (8.1%). Fifteen patients had TDM performed during treatment. A clinical pharmacist was involved in evaluation of all TDM results. Over half of patients with TDM levels had at least 1 dose change made. A minority of patients (16.9%) experienced clinical failure. CONCLUSION: Clinical pharmacists should be involved in this complex care to optimize medication management through identification of drug interactions, tailoring antimicrobial dosing, managing TDM results, and providing adherence counseling.