Abstract
BACKGROUND: Myroides species, Gram-negative bacilli from the Flavobacteriaceae family, are typically considered low-virulence pathogens but have previously been described as extensively drug-resistant. This study investigates the clinical features and outcomes of Myroides infections. METHODS: We conducted a retrospective cohort study of patients hospitalized at Cleveland Clinic with Myroides infection. Infections were defined as a positive Myroides culture from a sterile site that were treated with an antibiotic to which the isolate was susceptible. Controls were hospitalized patients with a positive culture for Myroides, who did not meet the definition for infection. Survival for infected patients and uninfected controls was compared using Cox proportional hazards regression. RESULTS: Between January 2015 and September 2023, 52 positive Myroides species cultures were identified, with 21 deemed infections. A higher proportion of Myroides-infected patients than controls had diabetes mellitus. The most common infections were skin/soft-tissue infections (42.8%), osteomyelitis (33.3%), and urinary tract infections (19%); and 28.5% were bacteremic infections. All isolates were resistant to aminoglycosides, but the majority were susceptible to trimethoprim-sulfamethoxazole (81%), ciprofloxacin (57%), and meropenem (68%). The main antimicrobial treatments provided were meropenem, ciprofloxacin, and trimethoprim-sulfamethoxazole. A significant difference in survival was not found between patients with Myroides infection and uninfected controls (hazard ratio, 3.42; 95% confidence interval, .63-18.74; P = .16). CONCLUSIONS: All patients in this study had reasonable treatment options, belying previous reports of extensive antibiotic resistance in Myroides. Our small study did not detect a statistically significant decrease in survival among Myroides-infected patients compared to controls.