Coccidioides immitis Causing Septic Arthritis of an Ankle in the Setting of HIV
Author(s):
Kristopher McCall, OUHSC; William Ertl, OUHSC; Linda Salinas, OUHSC
Background: Septic arthritis is a well-known disease process. The incidence quoted in the literature ranges from 0.034% to 0.13% for nongonococcal arthritis. Predisposing conditions for non-traumatic septic arthritis are diabetes, RA, SLE, and HIV. The most common joints affected are the knee and hip. Fungal-caused septic arthritis is typically not seen other than in immunocompromised hosts, with Candida species being the most common. Coccidiomycosis is an infection endemic to the Southwestern United States. It typically induces pneumonia-like symptoms with severity correlating to the amount of endospores inhaled and host immune factors.
Hypothesis: N/A
Methods: This is a 42-year-old male with HIV who has been off his anti-retrovirals for four months. His CD4+ count upon admission was 37cells/µ with a viral load of 134,000 copies/ml. His previously negative coccidioides antibody increased to 1:8. He presented to the ER with dyspnea and was admitted for bilateral lower lobe infiltrates and suspected pneumonia. He complained of right Achilles pain for the last 3 weeks without any known injury. On his initial history and physical it was noted that he did have a decreased range of motion to his ankle. Five days after admission orthopedics was consulted for abscess versus septic arthritis. Upon aspiration of the right ankle 15 cc of purulent material was removed.
Results: A medial approach to the ankle was performed. A rush of purulent material was elucidated after opening the capsule, which was cultured. The wound was irrigated with normal saline prior to skin closure leaving the joint capsule open. Cultures grew C immitis from both the aspirate and the intra-operative samples. The patient also had C immitis in a brain abscess. Fluconazole was started the day of his irrigation and debridement. The duration of his hospital stay was 15 days. He did re-present with ankle pain one month later and was found to have immune reconstitution syndrome. He did not require another irrigation.
Conclusions: This is a case of reactivation of C immitis causing septic arthritis of the ankle. This case demonstrates that hematogenous seeding of joints, even atypical fungal agents that cause respiratory infections, can seed and affect any joint. The initial treatment did not change from typical septic arthritis and this patient has done well. It is important to involve infectious disease colleagues, especially in atypical presentations, for planning and decision making regarding therapeutic agents and duration of therapy.