Adverse Events Releated to Antibiotic Use in Patients with Myasthenia Gravis

BACKGROUND: Myasthenia gravis is a medical condition involving the neuromuscular junction, characterized by weakness and fatigue of voluntary muscles. While the understanding of myasthenia gravis has progressed over the years, questions remain regarding which antimicrobial agents can be administered safely to these patients. Traditionally, aminoglycosides and fluoroquinolones have been avoided in this patient population, while other antimicrobials may be prescribed with caution. With minimal literature to guide practice, our aim was to review antimicrobial prescribing in patients with myasthenia gravis at our institution. METHODS: We conducted a retrospective chart review of adult patients 18 years of age and older with a diagnosis of myasthenia gravis who were admitted from January 2012 through December 2015. Charts were reviewed for the receipt of any antimicrobial during the course of hospitalization and any adverse events related to receipt of antimicrobial agents. RESULTS: 205 patients with a diagnosis of myasthenia gravis were admitted to our institution during the study period. 132 (64.4 %) patients were female and ages ranged from 20 to 98 with a median age of 59 years. 159 (77.6 %) patients received at least 1 dose of an antimicrobial agent during their hospitalization. It was notable that 12.2 % and 11.7 % of patients received at least 1 dose of ciprofloxacin or levofloxacin, respectively. Additionally, 3.9 % of patients received at least 1 dose of an aminoglycoside (gentamicin or tobramycin). Five patients experienced a worsening of their myasthenia gravis symptoms with antibiotic use; 2 cases involved levofloxacin and 1 case each involved ciprofloxacin, cefazolin, or clindamycin. Of note, the average duration of therapy prior to symptoms being noted was 2.6 days. CONCLUSION: This study highlights the wide variation in antimicrobial prescribing for patients with myasthenia gravis. Our chart review identified few adverse reactions exacerbating disease symptoms related to antimicrobial use. As it is still unclear the exact mechanism for the development of reactions in select patients with myasthenia gravis, further research may be needed to elucidate this information. DISCLOSURES: All authors: No reported disclosures.