Miller Fisher Syndrome and polyneuritis cranialis in COVID-19.

To report two patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) who acutely presented with Miller Fisher syndrome and polyneuritis cranialis, respectively.Patient data were obtained from medical records from the University Hospital "Príncipe de Asturias", Alcalá de Henares, Madrid, Spain and from the University Hospital "12 de Octubre", Madrid, Spain.The first patient was a 50-year-old man who presented with anosmia, ageusia, right internuclear ophthalmoparesis, right fascicular oculomotor palsy, ataxia, areflexia, albuminocytologic dissociation and positive testing for GD1b-IgG antibodies. Five days before, he had developed a cough, malaise, headache, low back pain, and a fever. The second patient was a 39-year-old man who presented with ageusia, bilateral abducens palsy, areflexia and albuminocytologic dissociation. Three days before, he had developed diarrhea, a low-grade fever, and a poor general condition. The oropharyngeal swab test for coronavirus disease 2019 (COVID-19) by qualitative real-time reverse-transcriptase-polymerase-chain-reaction assay was positive in both patients and negative in the cerebrospinal fluid. The first patient was treated with intravenous immunoglobulin and the second, with acetaminophen. Two weeks later, both patients made a complete neurological recovery, except for residual anosmia and ageusia in the first case.Our two cases highlight the rare occurrence of Miller Fisher syndrome and polyneuritis cranialis during the COVID-2 pandemic. Neurological manifestations may occur because of an aberrant immune response to COVID-19. The full clinical spectrum of neurological symptoms in patients with COVID-19 remains to be characterized.