Presentation
Diabetic with foot swelling and chronic ulcer. Now fever.
Patient Data
Extensive soft tissue lucency within the heel suggests infection secondary to gas forming organisms. A sinus is seen in the subcutaneous soft tissues on the lateral projection, extending from the skin surface into the heel and communicating with the large multilocular gas-filled cavity. No osseous changes to suggest osteomyelitis. Vascular calcification is noted.
Case Discussion
The patient went to theater for debridement which drained pus within several communicating soft tissue abscesses. Normal cortical bone of the calcaneus was encountered with no intraoperative features of osteomyelitis. Pseudomonas aeruginosa was cultured with is a non-fermenter (i.e. won't produce gas).
Personal discussion with both an Infectious Diseases Physician and Microbiologist about the case who offered the following opinions:
- the P. aeruginosa cultured would have been from the skin and there would almost certainly have been other organisms within the abscess, including fermenters
- a lot of diabetic foot infections contain a variety of low-level organisms
- on review of prior cultures of this patient, Staphylococcus aureus was grown from the same wound which, although rare, can produce gas within soft tissues