Successful treatment of subcutaneous phaeohyphomycosis owing to Exophiala jeanselmei with oral terbinafine

Cutaneous Phaeohyphomycosis of the Right Hand Caused by Exophiala jeanselmei: A Case Report and Literature Review

Exophiala spp. is increasingly reported as a pathogen causing the cutaneous, subcutaneous or invasive infection. In this report, we present a case of cutaneous phaeohyphomycosis due to E. jeanselmei on the right hand of a farmer, who suffered from this disease three years ago which had not been definitely diagnosed until he was admitted to our hospital. In our hospital, a potential fungal pathogen was observed by histopathological examination, and then was recovered and identified as E. jeanselmei by sequencing its internal transcribed spacer region. After 4 weeks of antifungal treatment, his hand recovered very well. To investigate the in vitro susceptibility of E. jeanselmei isolates to antifungal agents and compare the characteristics of their related infections among immunocompetent and immunocompromised patients, we reviewed 84 cases published in PubMed database between 1980 and 2020.

Eumycetoma Medical Treatment: Past, Current Practice, Latest Advances and Perspectives

Mycetoma is a neglected tropical disease that is associated with poor communities and socioeconomically impaired individuals in the tropical and sub-tropical areas. Interestingly, the disease is caused by either bacteria (actinomycetoma) or fungus (eumycetoma). The latter form of the disease, eumycetoma, is the most common type in Africa. Eumycetoma is characterized by a prolonged disease duration and low cure rate. The effective case management of eumycetoma largely depends on the accurate diagnosis and identification of the causative agent to the species level and evaluating its susceptibility to the available drugs. This review summarizes the currently available and used antifungal agents for the treatment of eumycetoma and discusses optimizing the newly developed antifungals as a potential second line for eumycetoma treatment.

Successful Terbinafine Treatment for Cutaneous Phaeohyphomycosis Caused by Trematosphaeria grisea in a Heart Transplanted Man: Case Report and Literature Review

Phaeohyphomycosis is a chronic infectious disease caused by dematiaceous fungi. It is characterized by the presence of pigmented septate mycelia within tissues. In the case of superficial infection, the lesion(s) chronically evolve(s) toward painless pseudo-tumor(s) of the soft parts. We report herein the original case of a heart transplanted man who exhibited phaeohyphomycosis of the left hand, with no mention of travels in endemic areas. Trematosphaeria grisea was identified as the causative agent, which is quite innovative since this species has been rather described in mycetoma. The antifungal treatment initially based on isavuconazole alone was not sufficient to cure the patient. In contrast, its association with local terbinafine ointment allowed total clinical improvement. This finding is unusual as diagnosis of phaeohyphomycosis caused by T. grisea is uncommon in nontropical countries, and as the outcome appeared successful by the means of add-on therapeutic strategy with terbinafine.

Mycetoma medical therapy

Medical treatment of mycetoma depends on its fungal or bacterial etiology. Clinically, these entities share similar features that can confuse diagnosis, causing a lack of therapeutic response due to inappropriate treatment. This review evaluates the response to available antimicrobial agents in actinomycetoma and the current status of antifungal drugs for treatment of eumycetoma.

Subcutaneous phaeohyphomycosis on the scrotum caused by Exophiala jeanselmei: case report

Subcutaneous phaeohyphomycosis is a disease caused by dematiaceous fungi that develops mainly in immunocompromised patients. Lesions are generally located on the lower limbs. The present report describes a case of phaeohyphomycosis in an immunocompetent patient in whom a subcutaneous abscess was located in an unusual site, on the left hemiscrotum. The abscess was treated successfully with oral fluconazole associated with surgical excision.

Melanized fungi in human disease

Melanized or dematiaceous fungi are associated with a wide variety of infectious syndromes, including chromoblastomycosis, mycetoma, and phaeohyphomycosis. [corrected]. Many are soil organisms and are generally distributed worldwide, though certain species appear to have restricted geographic ranges. Though they are uncommon causes of disease, melanized fungi have been increasingly recognized as important pathogens, with most reports occurring in the past 20 years. The spectrum of diseases with which they are associated has also broadened and includes allergic disease, superficial and deep local infections, pneumonia, brain abscess, and disseminated infection. For some infections in immunocompetent individuals, such as allergic fungal sinusitis and brain abscess, they are among the most common etiologic fungi. Melanin is a likely virulence factor for these fungi. Diagnosis relies on careful microscopic and pathological examination, as well as clinical assessment of the patient, as these fungi are often considered contaminants. Therapy varies depending upon the clinical syndrome. Local infection may be cured with excision alone, while systemic disease is often refractory to therapy. Triazoles such as voriconazole, posaconazole, and itraconazole have the most consistent in vitro activity. Further studies are needed to better understand the pathogenesis and optimal treatment of these uncommon infections.

Phaeohyphomycosis caused by Exophiala jeanselmei in a patient with polymyalgia rheumatica

An 87-year-old man, a gardener in Okinawa, first noticed a tumor on the dorsum of his right hand in November 2005. He had been taking prednisolone for the treatment of polymyalgia rheumatica since 2000. A nearby dermatologist incised the tumor for pus drainage in February 2006. In April of the same year, the dome-like tumor reappeared. The same treatment was repeated. Because the culture of the pus revealed fungi at that time, terbinafine hydrochloride and minocycline were administrated under the diagnosis of a deep fungal infection. After a short remission, the tumor recurred in November of the same year and in May and August of 2007 regardless of the repeated incision and pus drainage. He was referred to our hospital on 27 September 2007. His first physical examination at our outpatient office showed a skin-colored, well-demarcated, multilocular, cystic subcutaneous tumor on the dorsum of his right hand. Histopathological examination revealed a pseudocyst with fibrous walls of connective tissue. Continuous, bead-like hyphae, positive with periodic acid-Schiff stain and Grocott stain, were found within the pseudocyst. Morphological and molecular biological examinations of the separately cultured specimens identified the causative agent as Exophiala jeanselmei. The entire cyst was removed under local anesthesia, and an artificial dermis made of silicon membrane was applied to the wound. Skin graft was performed in November after confirming no recurrence of the fungal infection. Terbinafine hydrochloride 125 mg/day has continued. No recurrence has been observed up to now.

Exophiala spinifera and its allies: diagnostics from morphology to DNA barcoding

Diagnostic features of morphology, physiology, serology and genetics of species belonging to the Exophiala spinifera clade (including 11 species: Exophiala oligosperma, E. spinifera, E. xenobiotica, E. jeanselmei, E. exophialae, E. nishimurae, E. bergeri, E. nigra, Rhinocladiella similis, Ramichloridium basitonum and Phaeoannellomyces elegans), comprising a large number of human-associated Exophiala species, are summarized. Several species have closely similar morphological characters and physiological profiles. Taxonomy is therefore primarily based on sequence diversity of the Internal Transcribed Spacer (ITS) region of ribosomal DNA (rDNA). Multilocus sequencing has shown that ITS is reliable for identification of the species in this clade, and is a therefore a good candidate for barcoding species of Exophiala. Species-specific fragments were searched in the ITS region of species in the Exophiala spinifera clade and can be used to design probes for diagnosis by hybridization.

Use of terbinafine in rare and refractory mycoses

Terbinafine is the only systemic allylamine antifungal currently available. Its mechanism of action is unique and sets it apart from other agents. Although it is primarily used for dermatophyte infections, such as onychomycosis and tinea pedis, terbinafine has broad in vitro activity against a variety of non-dermatophyte fungal pathogens, including Candida spp. and many molds. In addition, synergistic activity is noted with other antifungals, notably triazoles. Multiple case reports exist of its use for unusual and refractory fungal infections, but no systematic review is available. We review the current literature with regard to in vitro data and clinical experience with terbinafine in the treatment of rare and refractory mycoses.