Several subcutaneous and deep-seated
mycoses are either observed more frequently in the tropical areas or are restricted to certain regions within the tropics. These
mycoses include sporotichosis,
chromoblastomycosis,
entomophthoromycosis,
eumycetoma,
lobomycosis, and
paracoccidioidomycosis. In
sporotrichosis and
paracoccidioidomycosis,
therapy often results in either complete resolution or marked improvement. For decades
sporotrichosis has been treated successfully with
potassium iodide, but recently the
triazole compounds, especially
itraconazole, have proved effective and free of major side effects. The usual
therapy for
paracoccidioidomycosis is
sulfonamides or
amphotericin B; the former requires prolonged treatment, whereas the latter causes a significant degree of toxicity. Various
azole derivatives (
ketoconazole,
fluconazole,
saperconazole, and
itraconazole) allow shorter treatment courses, can be given orally, and are more effective. Presently,
itraconazole is the
drug of choice.
Chromoblastomycosis is a difficult condition to treat, especially if it is caused by Fonsecaea pedrosoi. Several therapeutic approaches have been used, including heat, surgery,
cryotherapy,
thiabendazole,
amphotericin B combined with
flucytosine, and
azole derivatives, but their success has been modest. A 65% response rate has been obtained with
itraconazole given for periods of 6 to 19 months; in limited trials,
saperconazole appears to be more effective and requires shorter treatment courses. Only a few patients with
eumycetoma respond to
therapy; 70% of patients with Madurella mycetomatis respond to prolonged treatment with
ketoconazole.
Griseofulvin has been tried in nonresponders with partial success. Limited data in patients with Fusarium species
eumycetoma indicate good responses to
itraconazole.
Eumycetoma caused by Pseudallescheria boydii or Acremonium species has been refractory to
therapy.
Therapy of
entomophthoromycosis is also difficult because the diagnosis is usually established late and not all patients respond to
therapy; this situation applies to
infection caused by either Basidiobolus haptosporus or Conidiobolus coronatus. Although there is no consensus, African physicians prefer to use
potassium iodide or
trimethoprim-sulfamethoxazole. Isolated reports indicate that the
azole derivatives, including the
triazoles, may be effective. As for
lobomycosis, all attempts at medical treatment have failed. Surgery is successful only when the lesion is small and can be fully resected; repeated
cryotherapy appears to be more successful.