Plesiomonas shigelloides Bacteremia: A Scoping Review of Epidemiology, Clinical Characteristics, Outcomes, and Implications of Antimicrobial Stewardship

<i>Plesiomonas shigelloides</i>, an aquatic Gram-negative bacillus often associated with self-limiting gastroenteritis, has been reported worldwide. However, to date, no reviews have specifically investigated <i>P. shigelloides</i> bacteremia, which is rare and potentially fatal. This scoping review aimed to examine the existing literature to identify the epidemiology, clinical characteristics, antimicrobial susceptibility, and outcomes of <i>P. shigelloides</i> bacteremia. A PRISMA-ScR-guided search of PubMed, Scopus, Web of Science, and Embase identified 22 published cases, all reported as single-patient case reports. Cases were globally distributed, with the majority reported from the Americas and Europe. The median patient age was 46 years. The case fatality rate was 27.3% (<i>n</i> = 6/22). Most patients had identifiable host risk factors, particularly hematological disorders, neonatal status, or immunocompromised status, and environmental exposure such as raw seafood consumption or contact with freshwater. Clinical presentations were heterogeneous, commonly including fever and sepsis or septic shock. Microbiologically, <i>P. shigelloides</i> demonstrated consistent intrinsic resistance to ampicillin while retaining susceptibility to multiple antimicrobial classes. Poor outcomes were more closely associated with host factors and delayed presentation than with antimicrobial resistance. Early diagnosis, targeted therapy, and antimicrobial stewardship are essential for optimizing outcomes in this rare but severe infection.