Background: Chromomycosis is a chronic fungal infection of the skin and subcutaneous tissue caused by various dematiaceous fungi, the most common of which is Fonsecaea pedrosoi. The disease is difficult to treat.
Methods: Twenty-two chromomycosis patients treated by cryosurgery with liquid nitrogen as the sole or associated therapy were studied. Diagnosis was confirmed by direct examination of KOH cleared specimens, culture, and histology, according to a method previously described by Pimentel et al. (Pimentel ERA, Castro LGM, Cucé LC, Sampaio SAP. Treatment of chromomycosis by cryosurgery with liquid nitrogen. J Dermatol Surg Oncol 1989; 15: 72-77). Small lesions were frozen in a single session, whilst larger lesions were frozen in small parts. All patients received double freeze-thaw cycles. An author-created severity index, based on the extent of the diseased area, number of lesions, presence of complications (lymphedema, ulceration, and secondary infection) and unresponsiveness to previous treatments, was used to determine disease severity.
Results: Fonsecaea pedrosoi was isolated from all but one patient. Caucasian (50.0%) males (4.5 : 1.0) were most commonly affected. The average number of cryosurgery sessions per patient was 6.7, varying from one to 22 sessions. The duration of treatment lasted for up to 126 months. Nine patients (40.9%) were considered to be cured (clinically disease-free period of at least 3 years), eight (36.4%) were under observation (clinically disease-free but less than 3 years of follow-up), two (9.1%) were under treatment (still with active lesions), and three (13.6%) were classified as unsuccessful. The average cure period was 7.5 years, varying from 3 to 16 years. Five (55.6%) of the nine cured patients had been cured for periods exceeding 9 years. Six (66.7%) of the nine cured patients were classified as having mild, two (22.2%) severe, and one (11.1%) moderate disease.
Conclusions: Cryosurgery with liquid nitrogen is an option in the treatment of chromomycosis.