Neurophysiological confirmation of phrenic nerve affection in patient with dyspnea and herpes zoster

Introduction. Herpetic lesion of the phrenic nerve is very uncommon. These lesions are usually unilateral and for most clinicians, the clinical manifestation of herpes zoster in the cervical or thoracic region and diaphragmatic paralysis on the same side is sufficient for making a diagnosis of segmental herpes zoster phrenic nerve palsy. We report a patient, who had a classic clinical picture, in which we confirmed phrenic nerve affection on nerve conduction study. Case report. A 58-year-old female patient, presenting with shortness of breath. The patient had a herpetic rash of her right shoulder two and a half months earlier. The elevation of the right hemidiaphragm was seen on chest X-ray imaging. Asymmetry was evident on nerve conduction study of the phrenic nerve: prolonged latency and reduced amplitude of her right phrenic nerve. The patient was treated by acyclovir, pregabalin, and B complex vitamins. After 6 months the motor deficit was completely reduced. Conclusion. Nerve conduction study of the phrenic nerve is useful in making the definitive diagnosis. Good outcome, as in this patient, is rare in patients with this diagnosis and may be linked to timely treatment with acyclovir.