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Updated: Aug 4, 2025

Posterior Approach for Debridement of the Psoas Abscess
Published on: March 2, 2020
Perinephric Abscess Extending to the Psoas Muscle and Causing a Nephro-Cutaneous Fistula
Mulham Alom1, Victoria Bengualid2
1Internal Medicine, St. Barnabas Hospital Health System, Bronx, USA.
Abstract:
We present a case of a 76-year-old male with dementia transferred from a nursing home with a fever and an abscess on his back. Workup revealed an extensive perinephric abscess, which extended to his psoas muscle, with an additional fistula to his back where the abscess was noted. The extent and tracking of the perinephric abscess were unusual as well as the organisms isolated, Citrobacter koseri and Bacteroides species.
Insights
A rare case of extensive perinephric abscess caused by Citrobacter koseri and Bacteroides species in an elderly male with dementia is presented. The unusual abscess tracking and fistula formation highlight diagnostic challenges in complex patients.
Area of Science:
- Infectious Diseases
- Nephrology
- Urology
Background:
- Perinephric abscesses are collections of pus in the space around the kidney.
- They can be caused by various bacteria, often originating from urinary tract infections.
- Unusual presentations and causative organisms necessitate case reports for broader understanding.
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