Chromoblastomycosis caused by Chaetomium funicola: a case report from Western Panama

Abstract

Little is known about opportunistic fungi causing skin lesions in tropical countries such as Panama. We report an 83-year-old man from Chiriquí, Western Panama, with crusted skin lesions covering tumorous masses resembling Bowen's disease of the skin on the dorsum of his right hand. Fungal cultures were obtained on different nutrient media from disinfected superficial skin scrapings and fragments taken from a deep skin biopsy. Deep skin biopsy showed the presence of globose, dark fungal cells in the upper and lower dermis, sometimes in abscesses or giant cells, indicating chromoblastomycosis. All fungal fragments plated on nutrient media yielded colonies of Chaetomium funicola which was identified based on morphological observations and molecular sequence data of large ribosomal subunit rDNA. Treatment with fluconazole was ineffective. Further treatments could not be applied because of the patient's advanced age, low compliance, and limited resources in a rural, tropical environment. For the first time, C. funicola is confirmed as an opportunistic fungus causing superficial and deep cutaneous lesions. Up to now, the only known clinical record of this species is a tentative identification as an agent of deep mycosis.

Black Molds and Melanized Yeasts Pathogenic to Humans

“…Brain infection is sometimes seen in individuals during illicit intravenous drug use (Abbott et al 1995). A chromoblastomycosis-like infection by C. funicola was reported by Piepenbring et al (2007); this is an exceptional case of this disease caused by a fungus in the Herpotrichiellaceae. The distinctive feature of Chaetomium species is the presence of pronounced hairs, or setae, on the spherical to pyriform fruit bodies.…”

Chromoblastomycosis

“…The epidemiological data are similar to those for Mexico, with the prevailing fungus isolated being F. pedrosoi, although other species have also been reported. Among these reports was the exceptional report of CBM caused by Chaetomium funicola in Chiriquí, western Panama (117).…”

Melanized Fungi in Human Disease

“…They can also cause other clinical syndromes, often leading to confusion in the literature as some authors refer to any disease caused by these fungi as "_______ chromoblastomycosis" (66). Other fungi have been implicated, though some reports do not clearly describe the pathognomonic features and so are questionable (594). It is not understood how and under what conditions sclerotic bodies are formed in tissue.…”