Immune Reaction to COVID-19 May Play a Role in the Clinical Onset of Multiple Sclerosis

Researchers recently reported on a case of initial presentation of demyelinating disease (presenting as optic neuritis) in a 29-year-old woman with a medical history of asthma and rhinoconjunctivitis who was diagnosed with COVID-19. The patient presented with worsening right-eye visual acuity and an upper altitudinal defect. She experienced further decline in visual acuity and visual field defect, associated with constant retro-ocular pain that worsened with eye movement.

She began experiencing COVID-19 symptoms, including anosmia and dysgeusia associated with asthenia and proximal myalgias in her limbs (although this symptom lasted only 1 week), 2 to 3 weeks prior to presenting with ocular symptoms.

On examination, the patient was found to have 20/200 visual acuity, as well as papillitis and an afferent pupillary defect in her right eye. Orbital magnetic resonance imaging (MRI) tests found a right-sided optic nerve lesion with significant contrast enhancement, while brain MRI revealed sparse supratentorial periventricular demyelinating lesions, although no infratentorial or cortical/juxtacortical lesions. Spinal cord MRI results were unremarkable.

Laboratory analysis of cerebrospinal fluid (CSF) serum samples from the patient did not detect anti-myelin oligodendrocyte glycoprotein or aquaporin-4 antibodies but did find oligoclonal IgG bands. The patient tested positive for IgC and IgM on immunologic testing; polymerase chain reaction analysis of CSF and nasopharyngeal exudate were negative.

The patient was treated with 3 courses of daily 1-g methylprednisolone followed by a tapering regimen of oral corticosteroids, resulting in progressive improvement of her ocular pain and visual acuity.

In their discussion of these results, the researchers wrote that there is ample evidence of links between viral infection and demyelinating diseases, including data showing that Epstein-Barr infection is a risk factor for multiple sclerosis (MS), and that several other viruses are associated with more frequent and severe MS relapses. Furthermore, they noted that human coronavirus has been found in the brain tissue of patients with MS and intrathecal synthesis of human anti-coronavirus antibodies has been observed in CSF samples from patients with MS.

Because the patient met the criteria for MS diagnosis and presented with non-enhancing periventricular lesions, the researchers speculated that genetic or previous environmental factors had initiated the pathogenic process prior to COVID-19 infection. In this patient, COVID-19 infection “may have acted as a precipitating factor rather than multiple sclerosis being a direct consequence of the infection,” they wrote. This reinforced their theory that COVID-19 may be a neurologic autoimmunity trigger, similar to other viral infections.

Source

Palao M, Fernandez-Diaz E, Gracia-Gil J, et al. Multiple sclerosis following SARS-CoV-2 infection. Mult Scler Relat Disord. 2020;45:102377.