Chromoblastomycosis

Key Features

• A chronic, principally tropical cutaneous infection

• Usually affects older men who are agricultural workers

• Caused by several species of closely related black molds

• Fonsecaea pedrosoi and Cladiophialophora carrionii are most common etiologic pathogens

Clinical Findings

• Lesions usually follow puncture wounds

  • Occur most frequently on lower extremity

  • Begin as a papule or ulcer

• Over months to years, papules enlarge to become vegetating, papillomatous, verrucous, elevated nodules along with scarring

• Lesions may vary in appearance and have been classified into five categories

  • Nodular

  • Verrucous or warty

  • Plaque (infiltrative or erythematous)

  • Tumoral

  • Atrophic

• Secondary bacterial infection may occur

• Elephantiasis as well as squamous cell cancers may result

Diagnosis

• Potassium hydroxide preparations of pus or skin scrapings are helpful, showing brown, thick-walled, spherical, sometimes septate cells

• Punch or excisional biopsy specimens are also sensitive for diagnosis

Treatment

• Itraconazole, 200–400 mg orally once daily for 6–18 mo, achieves response rate of 65%

• Terbinafine (500–1000 mg/day orally) may be equivalent to itraconazole; the two may be useful in combination

• 5-fluorocytosine in combination with one of the above drugs also has been shown to be active, but adverse events with this drug have to be monitored carefully

• Photodynamic therapy combined with antifungal drugs has been used successfully as have immunomodulatory drugs like imiquimod