SAN DIEGO — Although deep fungal infections are rarely seen in North American children, they can present in those who visit or emigrate from tropical or subtropical areas of the world, Hector Caceres-Rios, M.D., said at the annual meeting of the Society for Pediatric Dermatology.
Dr. Caceres-Rios, professor of dermatology at Cayetano Heredia University, Lima, Peru, discussed several deep fungal infections:
▸ Mycetoma. This infection is seen mostly in Africa, India, Mexico, and Brazil. It typically peaks in the 3rd to 5th decade of life, but in Mexico it has been reported in 35% of citizens aged 16–30 years.
Infection occurs from inoculation with thorns, splinters, and sometimes animal bites, and incubation ranges from weeks to years. The disease course can last from months to decades.
The two main forms are eumycotic mycetoma and actinomycotic mycetoma.
Eumycotic mycetoma is typically restricted to the lower limbs (the foot in 70% of cases).
Causative agents include eumycota, dark grains, and white grains.
Eumycotic mycetoma is characterized by a painless swelling with multiple fistulae that discharge grains.
It may spread to the spinal cord, muscles, bones, and viscera. Treatment includes surgery and long-term use of ketoconazole or itraconazole.
Actinomycotic mycetoma is clinically similar to eumycotic mycetoma but is more painful. Causative agents typically include the Nocardia and Streptomyces species of aerobic bacteria.
Nocardia brasiliensis may cause inflammation at the affected site, while Actinomadura madurae causes the site to take on a “woody consistency,” he said.
Long-term antimicrobial therapy with streptomycin plus sulfamethoxazole and trimethoprim is required for these patients.
▸ Sporotrichosis. This infection is caused by skin injury with contaminated material or inhalation into the lungs. The culprit is Sporothrix schenckii, a dimorphous fungus. The infection primarily affects cutaneous tissue and lymphatic tissue but may also affect bones, joints, and viscera.
Dr. Caceres-Rios said that Mexico, Peru, and Colombia are the major endemic areas. Incubation varies from 1 week to 6 months, and first lesions usually appear on the extremities, followed by regional adenopathy. Treatment involves itraconazole 5 mg/kg per day for 16 weeks.
The infection occurs mainly in adults, but in some endemic areas of Peru, 60% of the cases occur in children under age 15.
▸ Chromoblastomycosis. This infection is caused by pigmented dematiaceous fungi, which generate dark yeasts. The disease is most prevalent in Madagascar, Brazil, and the Caribbean, and it presents in five clinical forms: nodular, tumoral, verrucous, plaquelike, and scar.
The disease typically peaks in the 3rd to 5th decade of life, but infection in children has been reported (Ann. Trop. Paediatr. 1990;10:273–7). Adults commonly present with the verrucous form, whereas children typically have nodular and plaquelike lesions.
This disease “may be extremely indolent, lasting for more than 20 years,” Dr. Caceres-Rios said.
▸ Paracoccidioidomycosis. According to Dr. Caceres-Rios, this is “the most important systemic mycosis in Brazil, Peru, and Mexico.” This infection is caused by Paracoccidioides brasiliensis, a dimorphous fungus. Common signs include warty, ulcerated, crusty lesions on the face and limbs.
The disease peaks in middle age, but in Brazil nearly 6% of affected patients are children. Paracoccidioidomycosis is mainly a pulmonary infection, but it may disseminate to other organs.
The most common form, disseminated paracoccidioidomycosis, is characterized by pulmonary, mucocutaneous, and lymph node involvement. Oral lesions occur in 80% of adults with this form.
Skin lesions are usually painful ulcerative or verrucous plaques. He said he treats severe cases with amphotericin.
Eumycotic mycetoma of the foot is treated with surgery and long-term use of ketoconazole or itraconazole.
Localized sporotrichosis in a child is treated with itraconazole 5 mg/kg per day for 16 weeks. Photos courtesy Dr. Hector Caceres-Rios