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

Herpes zoster infections are frequently observed after allogeneic bone marrow transplantation (alloBMT). In the majority of cases, the infection is restricted to specific dermatomes and responds to oral acyclovir, without visceral dissemination. We report the case of a 40-year-old male who developed dermatomal herpetic infection 8 months post alloBMT. The herpetic rash responded well to treatment with high-dose oral acyclovir. However, within a week of cessation of therapy, the patient re-presented with dermatomal zoster and meningoencephalitis. Although the cutaneous lesions resolved with intravenous acyclovir, clinical features of meningoencephalitis persisted, along with evidence of varicella zoster virus (VZV) DNA in cerebrospinal fluid (CSF). A satisfactory response to treatment was observed only after the addition of intravenous foscarnet to acyclovir. Based on our experience with this patient, we suggest that in a subset of alloBMT recipients, late dermatomal herpes zoster infections may respond only partially to treatment with standard oral acyclovir. The use of oral acyclovir preparations with higher bioavailability (valacyclovir) or intravenous acyclovir early on may prevent the considerable morbidity associated with disseminated zoster infection. Bone Marrow Transplantation (2000) 26, 795-796.