Segmental zoster paresis as a cause for persistent fever in an immunocompromised patient.

Herpes zoster reactivation is a frequently encountered condition that can result in several uncommon complications. This case report highlights one such frequently overlooked complication, segmental zoster paresis. We discuss a case of prolonged fever and lower limb weakness in an immunocompromised patient with breast cancer on active chemotherapy after resolution of a herpetiform rash in the L2, L3 and L4 dermatomes. Early investigation with lumbar puncture, looking for cerebrospinal fluid pleocytosis, varicella zoster virus detection by PCR or molecular testing and immunoglobulins against varicella zoster virus, should be undertaken to support the diagnosis. Nerve conduction studies, electromyography and MRI of the spine can sometimes help with neurolocalisation. Intravenous acyclovir and a tapering course of steroids can help with resolution of symptoms. The variegate presentation can make diagnosis challenging. Awareness and a high index of suspicion can prevent delays in diagnosis and treatment and improve patient outcomes.