AT ACDASM 2017
SYDNEY (FRONTLINE MEDICAL NEWS) – Chromoblastomycosis is best managed with a combination of surgery or cryotherapy, with an antifungal, based on a systematic review of 37 studies.
The results of these studies, none of which was randomized or controlled, highlighted challenges in the management of chromoblastomycosis, such as low cure rates and high relapse rates, particularly with chronic and extensive disease. “This is due to the indolent nature of the disease, which leads to a delayed diagnosis, so then the patient develops lymphedema and fibrosis, and the drug isn’t able to penetrate the sites of the lesion,” said Antonia Laino, MD, of the dermatology research center, University of Queensland (Australia).
Because the lesions are often asymptomatic and slow growing, some patients may have the infection for decades before seeking medical help. Complications from chronic disease can include ulceration, secondary bacterial infection, neoplastic transformation, and lymphatic damage resulting in lymphedema, she said at the annual meeting of the Australasian College of Dermatologists
Noncompliance was also found to be an issue because of side effects and the cost of long-term treatment.
Surgical and pharmacologic options were among the treatments used. Based on the results, Dr. Laino said surgery was recommended as the best treatment for small lesions, and could achieve cure rates of 100% for very small lesions. Cryotherapy was also used to treat chromoblastomycosis lesions, with variable success rates that were dependent on the size of the lesion and the frequency of freezing cycles. However, she suggested that larger lesions should be treated in serial sections, and warned of the risk of retractile scars with treatment over joints.
The most commonly reported drug therapies for chromoblastomycosis were itraconazole and terbinafine. With itraconazole, cure rates ranged from 15% to 80% over an average of 8.5 months of treatment. Pulsed itraconazole therapy, involving 1 week on and 3 weeks off treatment, achieved cure rates of 67%-100% across the studies. With terbinafine treatment, cure rates ranged from 40% to 75% over an average of 9 months of treatment.
In an interview, Dr. Laino said randomized controlled trials were needed to establish best practices for the treatment of chromoblastomycosis.
“I would also say that an antifungal plus a physical method [surgery or cryotherapy] is the way to go,” she said in the interview. As for pharmacotherapy, currently, “there’s the most support for use of itraconazole,” she said, but other antifungals that are being developed will also probably become good options, as studies of those become available. Refractory cases and very severe disease could be treated with a combination of itraconazole and terbinafine.
Chromoblastomycosis is a subcutaneous mycotic infection that is endemic worldwide, but is more common in tropical regions. It usually develops after injury to the skin, which allows entry of any one of several fungal pathogens including Fonsecaea pedrosoi, Phialophora verrucosa, and Cladophialophora carrionii. “Chromoblastomycosis can present with many different lesions, but the early lesions usually resemble a dermatophyte infection or begin as a papule,” Dr. Laino said. “Over time, the lesions will progress into the nodular, tumorous verrucous, cicatricial, and plaque types, and in advanced cases … you’ll see a lot of different lesions in one patient.”
No conflicts of interest were declared.