Plesiomonas shigelloides

Background

• Gram-negative bacillus in the Enterobacteriaceae
• Most commonly thought to be contracted by ingestion of undercooked, contaminated seafood, but may be a member of normal gut flora
  • Can also occur after water exposures, including natural disasters

Clinical Manifestations

• May be present in healthy individuals' stool
• Incubation period less than 48 hours, followed by gastroenteritis with nausea, vomiting, diarrhea (at times bloody), and fevers1
• Usually self-limited to a few days but can last up to 4 weeks
• Rare reports of bacteremia, as well as soft tissue infections, CNS infections (particularly in newborns), bone and joint infections, endophthalmitis, and pneumonia (particularly with near-drowning)

Management

• Generally self-limited diarrheal illness that is treated supportively
• For infections that require treatment:
  • Can use fluoroquinolones, azithromycin, or amoxicillin-clavulanic acid for 3 to 5 days if mild
  • Can use ceftriaxone or carbapenems if severe