[Usefulness of topical cidofovir treatment for recalcitrant molluscum contagiosum in immunocompromised children].

Molluscum contagiosum (MC) is common and often numerous and recalcitrant in immunocompromised children. The response to available treatments is frequently unsatisfactory. Cidofovir is a nucleoside analog of the deoxycytidine antiviral drug approved for the intravenous treatment of cytomegalovirus retinitis in AIDS patients. We report four cases of children, 5-8 years old, who developed extensive MC in the context of chemotherapy for acute lymphoid leukemia and who were treated with a cream containing cidofovir 1%. In all patients, the lesions began to regress within 2 to 4 months. For three patients, complete regression was observed in 7 to 9 months, and the children remained clear of recurrence. For one patient, partial regression was obtained after 17 months of treatment. No side effects have been observed. Treatment of MC in immunocompromised children is difficult because the usual treatments are inappropriate. Successful use of either topically or intralesionally administered cidofovir in several virally induced cutaneous diseases has been demonstrated and recently documented in the treatment of MC in immunocompromised adults. Conversely, its use in children is not documented. Although intravenous use of cidofovir may lead to severe adverse effects, one single case of a systemic side effect has been reported after topical use at a greater concentration, but no changes in laboratory data were observed. Topical cidofovir offers an effective and well-tolerated therapeutic alternative option for the treatment of MC in immunosuppressed children.