Bacterium
Aeromonas hydrophila
Freshwater rod, wound and gut infection
air-oh-MOH-nas hy-DROF-ih-luh
High-yield clue
Oxidase-positive freshwater rod causing wound infection after freshwater exposure and classically linked to medicinal leech therapy.
Overview
An oxidase-positive Gram-negative rod found in fresh and brackish water, studied as a cause of gastroenteritis and of wound infection after freshwater exposure.
Classification
- Gram-negative
- Rod
- Aeromonadaceae
- Facultative anaerobe
- Oxidase positive
Lab & identification clues
- Oxidase positive (distinguishes from Enterobacterales)
- Beta-hemolytic on blood agar vocabulary
- Freshwater/aquatic origin concept
- Resistant to ampicillin vocabulary
Associations
- Freshwater wound exposure transmission vocabulary
- Watery gastroenteritis presentation vocabulary
- Medicinal leech therapy association
Commonly confused with
- Vibrio vulnificus
- Pseudomonas aeruginosa
Frequently asked questions
What is Aeromonas hydrophila?
An oxidase-positive Gram-negative rod found in fresh and brackish water, studied as a cause of gastroenteritis and of wound infection after freshwater exposure.
What is the Gram stain of Aeromonas hydrophila?
Aeromonas hydrophila is Gram negative.
What are the lab clues for Aeromonas hydrophila?
Lab clues for Aeromonas hydrophila include Oxidase positive (distinguishes from Enterobacterales), Beta-hemolytic on blood agar vocabulary, Freshwater/aquatic origin concept, and Resistant to ampicillin vocabulary.
What is Aeromonas hydrophila commonly confused with?
Aeromonas hydrophila is commonly confused with Vibrio vulnificus and Pseudomonas aeruginosa.
Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.