EC Pulmonology and Respiratory Medicine

Multiple sclerosis (MS), an autoimmune condition can damage the central nervous system (CNS) [1]. Persistence of various symptoms, such as anosmia, insomnia, brain fog, muscle pain, cough, dyspnea, exercise intolerance, fatigue, and chest pain after acute COVID-19 stage that has been denominated long COVID-19 condition or post-COVID-19 syndrome have been reported in many COVID-19 cases [2]. Additionally, antimicrobial usage that would change gastrointestinal microbiota composition is the principal risk factors, including COVID-19 severity for the development of long COVID-19 condition [3], whereas antimicrobials are the major gut-microbiota disruption [4]. Not well-controlled steroid therapy and poorly regulated glycemia are other risk factors for COVID-19-related mucormycosis [5]. In patients with moderate to severe COVID-19 disease, Guillain-Barre´ syndrome (GBS), encephalitis, meningitis, and acute necrotizing encephalopathy have been found [6], particularly increasing in hospital-admitted patients [7] and have been found in autopsy-deceased cases and expressing-human anti-converting-enzyme 2 (ACE 2), by neuro-invasion in cerebrospinal fluid (CSF) of a patient with GBS [8,9]. Hematogenous dissemination and direct-peripheral-neuron-endings invasion, particularly olfactory nerve that is located very close to the expressing-ACE2 and TMPRSS2-olfactory epithelium allowing easy COVID-19-initial replication are the two principal routes of neuro-invasion of COVID-19 [10,11]. The diagnosis of MS is usually depended on clinical manifestations (muscle weakness, muscle stiffness and spasms, coordination loss, vision impairment, pain, urinary bladder and bowel function changes due to damages of the myelin sheaths (Figure 1 and 2), CSF analysis for oligoclonal antibody band and inflammatory biomarkers, neuroimaging (multifocal and scattered lesions through the white and grey matter of the brain and spinal cord) [12].

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11. Gasmi A., et al. “Neurological involvements of SARS-CoV-2 infection”. Molecular Neurobiology 3 (2021): 944-949.
12. Garg N and Smith TW. “An update on immunopathogenesis, diagnosis, and treatment of multiple sclerosis”. Brain and Behavior 9 (2015): e00362.