Acute abducens nerve palsy in a patient with the novel coronavirus disease (COVID-19)

To the Editor: I would like to highlight a few points pertaining to the recently published “Acute abducens nerve palsy in a patient with the novel coronavirus disease (COVID-19),”¹ which shows that abducens nerve palsy may represent part of the neurologic spectrum of COVID-19. Patients with COVID-19 infection may also have other impairments of extrinsic ocular motility. The case report of a 21-year-old who presented with a third cranial nerve palsy after a severe form of SARS-CoV-2 has been described; after the 7th day, the patient rapidly recovered from his diplopia.² SARS-CoV-2 is a neurotrophic virus that can cause increased intracranial pressure, affecting the sixth cranial nerve. Another action of the virus that may explain the alteration of ocular motility and its thrombotic action is venous and arterial circulations.^{2 , 3} Other viruses that can cause changes in extrinsic ocular motility may also shed light on the pathophysiology of SARS-CoV-2. Chikungunya virus, for example, causes the release of cytokines that have direct and indirect neurotoxic action. Immunohistochemistry tecnhiques have already demonstrated that infected neurons can undergo apoptosis.⁴