Varicella zoster meningoencephalitis following treatment for dermatomal zoster in an alloBMT patient

Herpes tester infections are frequently observed after allogeneic bone marr ow transplantation (alloBMT), In the majority of cases, the infection is re stricted to specific dermatomes and responds to oral acyclovir, without vis ceral dissemination. We report the case of a 40-year-old male who developed dermatomal herpetic infection 8 months post alloBMT, The herpetic rash res ponded well to treatment with high-dose oral acyclovir, However, within a w eek of cessation of therapy, the patient re-presented with dermatomal teste r and meningoencephalitis. Although the cutaneous lesions resolved with int ravenous acyclovir, clinical features of meningoencephalitis persisted, alo ng with evidence of varicella tester virus (VZV) DNA in cerebrospinal fluid (CSF), A satisfactory response to treatment was observed only after the ad dition of intravenous foscarnet to acyclovir, Based on our experience with this patient, we suggest that in a subset of alloBMT recipients, late derma tomal herpes tester infections may respond only partially to treatment with standard oral acyclovir, The use of oral acyclovir preparations with highe r bioavailability (valacyclovir) or intravenous acyclovir early on may prev ent the considerable morbidity associated with disseminated tester infectio n.