Multiphasic presentation of neuralgic amyotrophy associated with hepatitis E virus infection

Background The aim of this study was to further characterize the clinical phenotype of hepatitis E virus (HEV)-associated neuralgic amyotrophy (NA). Methods Three patients with HEV-associated NA underwent clinical, electrodiagnostic, and ultrasound assessment. Results In all patients, symptoms developed in several phases within a time span of 4-6 weeks, with three or more nerves involved. Symptoms were bilateral in two. In two patients, nerves of the trunk and the lower limb were affected as well. In one patient, three bouts occurred, each heralded by an increase in pain. In the other two, pain subsided quickly and nerve damage developed in two phases. Segmental enlargement with or without hourglass-like constrictions of the nerves was demonstrated by ultrasound in all. Conclusions The multiphasic presentation, together with the extensive multi-nerve involvement, may reflect a severe and protracted inflammation of the nerves in HEV-associated NA.