# Calcaneal Candida parapsilosis Osteomyelitis Causing Chronic Achilles Pain Following Achilles Corticosteroid Injection: A Case Report

## TL;DR

A 66-year-old woman developed a rare fungal infection in her heel after a corticosteroid injection, requiring long-term treatment.

## Contribution

This case report highlights the rare occurrence of calcaneal osteomyelitis caused by Candida parapsilosis following corticosteroid injection.

## Key findings

- Candida parapsilosis caused calcaneal osteomyelitis in a nondiabetic immunocompetent patient.
- Aggressive debridement and prolonged antifungal therapy for over six months successfully treated the infection.
- Direct inoculation through corticosteroid injections can lead to fungal osteomyelitis in degenerative tissues.

## Abstract

Calcaneal osteomyelitis is a challenging condition to manage. It is associated with risk factors, such as diabetes, and develops from traumatic wounds or pressure ulcers in which microorganisms can spread contiguously to bone. Calcaneal osteomyelitis with Candida parapsilosis is exceptionally rare. Candida osteomyelitis of the foot and ankle is uncommon, and treatment strategies are often based on limited clinical experience. We report such a case of osteomyelitis from Candida parapsilosis causing chronic insertional Achilles pain in a 66-year-old nondiabetic female following an Achilles corticosteroid injection. Candida parapsilosis is a fungal species that typically exists as a commensal of human skin and has high rates of nosocomial spread through the formation of biofilms on medical instrumentation. This case highlights that even in immunocompetent patients with well-controlled chronic conditions, direct inoculation through corticosteroid injection can lead to Candida osteomyelitis and Achilles infection. Degenerative tissue may predispose a person to the infection. Cultures for bacteria and atypical organisms, along with pathologic interpretation, are crucial for diagnosis. Treatment with aggressive debridement and prolonged antifungal therapy, greater than six months, proved successful for Candida osteomyelitis of the calcaneus in this case.