Probenecid Hypersensitivity in AIDS: a Case Report

Background Cidofovir plus probenecid is a new therapeutic alternative for refractory cytomegalovirus and acyclovir-resistant herpes infections in AIDS patients. Probenecid is used in conjunction with the antiherpetic medication (cidofovir) in order to reduce the incidence of nephrotoxicity by cidofovir. Objective To present therapeutic alternatives for successful administration of probenecid to AIDS patients who develop a hypersensitivity reaction to the medication. Methods and results We describe a patient with AIDS who was being treated with the cidofovir/probenecid combination for a perianal acyclovir-resistant herpetic infection. The patient subsequently developed a cutaneous hypersensitivity reaction to probenecid alone. A pretreatment regimen consisting of prednisone, H 1 and H 2 blockers was administered before the dosing of probenecid in order for the patient to continue with the antiviral therapy. Conclusion Cutaneous hypersensitivity reactions to probenecid may be seen more frequently with the increasing use of cidofovir in AIDS patients. Our pretreatment protocol is one therapeutic alternative to be considered in order to continue with probenecid.