A systematic review and meta-analysis of the global prevalence of fluoroquinolone resistant Morganella morganii clinical isolates.

Morganella morganii is an opportunistic pathogen that infects a variety of tissues. The increasing resistance of M. morganii to fluoroquinolones is a global public health concern. Hence, in this systematic review and meta-analysis, we aimed to determine the prevalence of fluoroquinolone resistance in M. morganii clinical isolates. We conducted a comprehensive search of the PubMed, Embase, ScienceDirect, and Scopus databases up to July 10, 2024, to identify studies on fluoroquinolone resistance in M. morganii. Studies that encompassed clinical isolates with fluoroquinolone susceptibility data were included. The prevalence of resistance was determined using a random-effects model, and heterogeneity was assessed using I2 statistics. Subgroup analyses were performed based on geographic region, study period, antibiotic susceptibility testing method, sample size, and study quality. Publication bias was evaluated using Begg's funnel plots and Egger's test. A total of 54 studies met the inclusion criteria, encompassing 45,440 clinical isolates. The pooled global prevalence of fluoroquinolone resistance in M. morganii was 21% (95% CI [16, 27]), with significant heterogeneity (I2 = 99.48%, p < 0.01). The resistance rate varied by region, with the highest rates observed in West Asia (62%) and Africa (55%) and the lowest in Australia (4%). The resistance rate also differed according to the type of fluoroquinolone, with the highest resistance recorded against the earlier-generation pefloxacin (88%), followed by nalidixic acid (27%), levofloxacin (25%), and ciprofloxacin (22%). There was no or lower resistance to newer fluoroquinolones, such as garenoxacin (0%). A temporal analysis revealed a trend of increasing resistance from 1993 to 2024, which peaked at 37% between 2018 and 2022 before declining slightly to 33% in recent years. Our findings highlight the need for continuous surveillance, improved antimicrobial stewardship, and the consideration of alternative treatment options to combat the rising resistance. However, the high heterogeneity among studies might be due to differences in study design, regions, antibiotic usage, and guidelines. Therefore, the pooled estimates should be interpreted with caution. Despite this variability, the results remain robust. Further studies are needed to explore the molecular mechanisms driving this resistance and potential therapeutic interventions.