# A Fatal Case of Necrotizing Soft Tissue Infection Caused by Aeromonas hydrophila Starting in the Thigh

## TL;DR

A man died from a severe thigh infection caused by Aeromonas hydrophila, highlighting the need for rapid treatment even with mild symptoms.

## Contribution

This case emphasizes the importance of early aggressive surgical intervention for NSTI caused by Aeromonas hydrophila.

## Key findings

- Aeromonas hydrophila can cause fatal NSTI in elderly patients without a known freshwater exposure history.
- Early hip dissection did not prevent death in this case due to rapid infection progression and secondary candidemia.
- Physical findings may appear mild despite severe underlying infection, requiring prompt surgical source control.

## Abstract

Necrotizing soft tissue infection (NSTI) remains a highly fatal disease. Among its causes, Aeromonas hydrophila is a Gram-negative bacillus endemic in freshwater environments that can cause fatal systemic infections in compromised hosts. The most important treatment of NSTI is source control done as soon as possible.

In this report, we describe a case of right femoral NSTI caused by Aeromonas hydrophila that was diagnosed based on minor physical findings, in which the patient died, despite early hip dissection. An 82-year-old man was admitted because of right femoral NSTI. Thirty hours after admission, we performed a right hip disarticulation for source control, and Aeromonas hydrophila was detected in the wound culture on the same day. Despite continuous treatment, he developed fungemia due to candida, eventually leading to his death.

In general, infection in a typical NSTI spreads from the extremities to the trunk, and appropriate debridement can save the patient's life. In the present case, the infection started from the thigh and may have progressed more rapidly than in other cases of NSTI.

It is important to assume Aeromonas hydrophila as the causative organism of NSTI in a compromised host, regardless of the history of exposure to a freshwater environment, depending on the patient's background and Gram staining results. Even if physical findings appear mild, a decision to perform hip dissection or pelvic hemisection for quick and aggressive source control may save the lives of similar patients.