Successful treatment of chromoblastomycosis of 10‐year duration due to Fonsecaea nubica

Abstract

We report a case of chromoblastomycosis due to the presence of large plaque and verrucous hyperplasia lesions on the left upper limb, with elbow abnormal activities, in a 56-year-old male. The diagnosis of chromoblastomycosis was based on gross and microscopic morphologies, histopathological examination and clinical manifestation. Molecular tools were applied to identifying the causative agent Fonsecaea nubica, which is rarely reported to be associated with chromoblastomycosis. The patient was initially treated orally with terbinafine (250 mg/day) and itraconazole (200 mg/day), subsequently patient received thermotherapy (45-50°C, 3 h/day) for 1 month. The patient was successfully cured. A literature review was performed to assess general features, treatment and outcome of chromoblastomycosis due to F. nubica. All the 5 reviewed patients were male, over 30 years old and their lesions occurred after traumatic inoculation.

Synergistic effect of terbinafine and amphotericin B in killing Fonsecaea nubica in vitro and in vivo

“…There are no recommended standards for the susceptibility testing result of Fonsecaea species. However, in comparison with previous antifungal susceptibility testing results for Fonsecaea species, both MIC of TBF and MIC of ITZ for F. nubica zssy0803 were higher 6 , 8 . VCZ could be useful to this patient since it has been proved to be effective to refractory CBM 22 .…”

“…TBF also has been proved to be very effective 4 , 14 - 16 . The combination therapy of ITZ and TBF is usually used in patients presenting refractory lesions 6 , 17 - 20 . In previous reports, ITZ and TBF showed good responses to treat CBM caused by F. nubica 17 , 21 .…”

“…Microscopic examination of the fungus revealed septate hyphae and conidiophores that were highly branched at the apices (Figure 1G). DNA of the fungus was extracted according to a method previously described 6 . The ribosomal DNA internal transcribed spacer (ITS) sequence was obtained using ITS-1 primer and ITS-4 primer.…”

Verrucous plaque on the hand

“…Chromoblastomycosis (CBM) is a chronic disease caused by the traumatic inoculation of dematiaceous fungi, mainly affecting the skin and subcutaneous tissue [1]. The pathogens are commonly Fonsecaea species and Cladophialophora carrionii [2]. This disease occurs primarily in tropical and subtropical regions, and is most prevalent in certain occupational groups, including farmers, gardeners, loggers, and suppliers of agricultural products [1].…”