Orthopedist's Onychomycosis as Source of Prosthetic Joint Infection with Candida Species

Background: Candida species are the fourth most common cause of nosocomial bloodstream infections in the US, but they are an uncommon cause of orthopedic surgical site infections. Candida species are estimated to comprise less than 1% of infections of total joint replacements. Case reports demonstrate an association between artificial fingernails and bacterial or candidal surgical site infection, but we are aware of no reports showing an association between native fingernail onychomycosis and Candida surgical site infections.

Objective:

Describe an outbreak of Candida prosthetic joint infections caused by onychomycosis in an orthopedic surgeon.

Methods: DNA fingerprinting of Candida isolates from the patients’ knees and the orthopedist’s fingernails was performed.

Results: In an 8 month period, 2 patients at our institution developed deep Candida surgical site infections after prosthetic knee replacement done by the same surgeon. The surgeon had onychomycosis, with fingernail cultures growing C. parapsilosis. DNA fingerprinting found identical strains of Candida parapsilosis from the knee of one of the patients and from nail clippings from the orthopedic surgeon. No other Candida infections complicating total joint surgery were identified in reviewing the last 5 years of such surgeries at our institution. The orthopedist was the only member of the surgical team present in the OR for both surgeries.

Conclusions:

These cases represent, to our knowledge, the first cases of Candida surgical site infections due to onychomycosis in a surgeon. The means by which the infections could have been transmitted to the patient are unclear. Isenberg et. al describe an outbreak of 8 Candida tropicalis sternal wound infections epidemiologically linked to a scrub nurse. Candida tropicalis was isolated from cultures of the nurse’s skin. No comparison of the DNA fingerprint of the isolates in the patients and in the nurse was performed in this study, and there was no mention of onychomycosis in the implicated nurse. Candida infections of total joint replacements are commonly highly morbid events, with resection arthroplasty required in most cases. We would recommend consideration of treatment of onychomycosis in the surgeon if Candida surgical site infections occur.