Polymyositis: The Comet Tail After COVID-19

Abstract

Infectious agents have been implicated in the pathogenesis of autoimmune disorders for decades. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is no exception. This became evident as the pandemic evolved. Once considered a respiratory pathogen only, SARS-CoV-2 is now linked to a variety of autoimmune rheumatic disorders such as rheumatoid arthritis, systemic lupus erythematosus, reactive arthritis, spondyloarthropathies, vasculitis, and inflammatory myopathy. Although the exact cause for muscle injury in the setting of coronavirus disease 2019 (COVID-19) is not established, autoimmune inflammatory damage is the most accepted mechanism. Moreover, SARS-CoV-2 can cause direct muscle damage and indirectly through a cytokine storm. Inflammatory polymyositis in relation to COVID-19 has seldom been reported in developing countries.Here, we report a unique case of inflammatory polymyositis in a 52-year-old lady. The patient presented with muscle weakness, generalized body aches, and fatigue occurring four months after recovering from mild COVID-19. She had muscle weakness of Medical Research Council (MRC) grade 3/5 involving the shoulders and pelvic girdle with elevated muscle enzymes. Electromyography revealed an active irritable myopathic process consistent with inflammatory polymyositis. She underwent magnetic resonance imagingguided muscle biopsy from the right thigh which revealed findings consistent with inflammatory myopathy. She was offered prednisolone and azathioprine. After four weeks of treatment, she had a remarkable improvement in her muscle strength to MRC grade 5/5.

A systematic review of the incidence, management and prognosis of new-onset autoimmune connective tissue diseases after COVID-19

“…Autoantibody serology also varied, with just three cases reporting positive ANA [ 19 – 21 ] and six reporting positivity for other autoantibodies, including NXP2, Mi2, Ku, and Ro [ 19 – 24 ]. In three cases with negative autoantibody serology, a diagnosis of myositis was made based on MRI muscle imaging, skin biopsy histology (consistent with dermatomyositis) and electromyography findings [ 23 , 25 – 27 ]. Three cases did not report serology or imaging justification of diagnosis, with these diagnoses based on classic symptoms including “malaise, muscle weakness and skin lesions” and “severe intractable pain in bilateral lower extremities and subjective pelvic girdle weaknesses’’ associated with a high creatinine phosphokinase level [ 25 , 28 , 29 ].…”

Post-COVID-19 Polymyositis: A Case Report

“…Nine other reported cases of polymyositis and dermatomyositis following COVID-19 infection [ 5 ]. Two of these cases were reported in the United States, with the other four and two occurring in Europe and Asia [ 5 ].…”

“…Nine other reported cases of polymyositis and dermatomyositis following COVID-19 infection [ 5 ]. Two of these cases were reported in the United States, with the other four and two occurring in Europe and Asia [ 5 ]. One study did not comment on their patient's clinical course of treatment; in another, the patient died due to COVID-19 infection.…”

“…Corticosteroids and immunosuppressive agents are the mainstays of therapy for polymyositis [ 2 ]. Recent literature has found inflammatory myopathies linked to Coronavirus disease 2019 (COVID-19), with only two reported cases of polymyositis following COVID-19 in the United States [ 5 ]. Because of these recent discoveries, we postulate that COVID-19 could be an etiology of polymyositis.…”

Acute Kidney Injury Following Posaconazole for Mucormycosis: SARS-CoV-2 as a Back-Seat Driver

“…Coronavirus disease 2019 (COVID-19) was initially thought to be a standalone respiratory illness [1]. As the pandemic is evolving, it has unraveled a variety of systemic complications.…”