Oral topical cidofovir: novel route of drug delivery in a severely immunosuppressed patient with refractory multidrug-resistant herpes simplex virus infection.

We present a case of serious treatment-refractory acyclovir- and foscarnet-resistant herpes simplex virus (HSV) type-1 orolingual infection that responded to oral cidofovir rinses after failure of acyclovir and foscarnet therapy. The use of 3% cidofovir in a saline rinse for refractory mucosal HSV infection appears promising but needs prospective evaluation.