Selective cranial multineuritis in severe COVID-19 pneumonia: two cases and literature review.

Objective To report two cases of cranial multineuritis after severe acute respiratory syndrome caused by coronavirus-2. Methods Patients' data were obtained from medical records of the clinical chart of dell'Angelo Hospital, Venice, Italy. Results The first patient is a 42-year-old male patient who developed, 10 days after the resolution of coronavirus-2 pneumonia and intensive care unit hospitalization with hyperactive delirium, a cranial multineuritis with asymmetric distribution (bilateral hypoglossus involvement and right Claude Bernard Horner syndrome). No albumin-cytologic dissociation was found in cerebrospinal fluid; severe bilateral denervation was detected in hypoglossus nerve, with normal EMG of other cranial muscles, blink reflex, and cerebral magnetic resonance with gadolinium. He presented a striking improvement after intravenous human immunoglobulin therapy. The second case is a 67-year-old male patient who developed a cranial neuritis (left hypoglossus paresis), with dyslalia and deglutition difficulties. He had cerebrospinal fluid abnormalities (albumin-cytologic dissociation), no involvement of ninth and 10th cranial nerves, diffuse hyporeflexia, and brachial diparesis. Discussion Cranial neuritis is a possible neurological manifestation of coronavirus-2 pneumonia. Etiology is not clear: it is possible a direct injury of the nervous structures by the virus through olfactory nasopharyngeal terminations. However, the presence of albumin-cytological dissociation in one patient, the sparing of the sense of smell, and the response to human immunoglobulin therapy suggests an immune-mediated genesis of the disorder.