Peripheral Nervous System Complications after COVID-19 Vaccination

While vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains crucial, neurological complications have been detected following the coronavirus disease 2019 (COVID-19) vaccination. The neurological complications of COVID-19 vaccination can be seen in both the central nervous system (CNS) and the peripheral nervous system (PNS). In this study, we reviewed PNS complications after COVID-19 vaccination, their underlying mechanisms, diagnosis, and management. Inflammatory polyneuropathy, small fiber neuropathy, Parsonage-Turner syndrome (PTS), cranial mononeuropathies, and myasthenia gravis (MG) have been reported following COVID-19 vaccination. Inflammatory polyneuropathy following COVID-19 vaccination should be diagnosed early based on clinical presentation and treated with supportive care, and immunoglobulin or plasmapheresis to prevent respiratory distress if required. It is important to differentiate peripheral from central facial paralysis after COVID-19 vaccination to rule out upper motor neuron damage, including stroke. Diagnosis of small fiber neuropathy in the setting of COVID-19 vaccination should be suspected in patients with dysesthesia, dysautonomia, and lower extremity paresthesia. A skin biopsy of the proximal or distal lower limb should generally be considered for diagnosing small fiber neuropathy following COVID-19 vaccination. Even though pain at the injection site is one of the most common symptoms after COVID-19 vaccination, shoulder pain lasting more than 3 weeks should raise the suspicion of severe complications such as PTS. In addition to a proper physical examination as a reliable diagnosis tool, needle electromyography can be considered to help the diagnosis of PTS following COVID-19 vaccination. In our opinion, despite complications after COVID-19 vaccination, the benefit of vaccination immunity should not be forgotten.