Foscarnet for cytomegalovirus retinitis in a patient with acquired immunodeficiency syndrome]

A 41-year-old man with acquired immunodeficiency syndrome (AIDS) developed cytomegalovirus (CMV) retinitis. Intravenous administration of ganciclovir arrested progression of the retinitis, but it was discontinued due to side effects of severe anemia, neutropenia, and thrombocytopenia. Reactivation of CMV retinitis occurred two weeks after stopping ganciclovir, and then forscarnet was given intravenously. The response was prompt with resolution of the retinitis. There was no progression of retinitis during the treatment. The patient experienced renal dysfunction as a side effect of foscarnet, but it was reversible. As with ganciclovir, foscarnet appeared to be an effective drug for CMV retinitis associated with AIDS. Both drugs have severe adverse events: foscarnet causes renal dysfunction and ganciclovir causes myelosuppression, that necessitated discontinuation of the therapy. We suggest that alternating ganciclovir and foscarnet administration, switching to other treatment on the basis of the clinical response and side effects of the drugs, is an efficacious regimen for the treatment of CMV retinitis associated with AIDS.