Phaeoacromonium parasitica (P. parasitica) is a rare cause of human fungal infection. It can manifest as either localized or disseminated infections, with the dissemination occurring in immunocompromised hosts. Our patient is a 70 year old male who presented with right knee pain and swelling over his right shin. The patient reported that he had injured the swollen area 8 years before when he had fallen on a sharp cypress stump. A portion of the stump became embedded in the subcutaneous tissue despite efforts to remove it. Since the injury the area would periodically swell then regress. Two weeks prior to his presentation the area rapidly increased in size and did not resolve. Physical exam revealed a 4 by 2.5cm flesh colored nodule with no signs of obvious inflammation. The nodule was soft, non-tender, well circumscribed and freely mobile. An excisional biopsy of the lesion revealed a hypocellular, centrally amorphous, necrotic mass surrounded by a thin palisade of histiocytes, all contained within a thick fibrous pseudocapsule. Fungal hyphae were demonstrated by Gomori methenamine silver staining. Subsequent cultures grew P. parasitica. The infection was treated with voriconazole followed by itraconazole. The organism was subsequently shown to be sensitive to both medications. This is only the fifteenth reported human infection with this organism and the first time anti-fungal sensitivities have been performed reported on an isolate.
Full conference title:
14th Annual Focus on Fungal Infections
- FFI 14th (2004)