key: cord-0984655-9cxm7j3n authors: Uslu, Sadettin title: Myositis due to COVID-19 date: 2021-02-15 journal: Postgrad Med J DOI: 10.1136/postgradmedj-2021-139725 sha: de2ea3abeaaa9429e5c3b73447a2828a063d313a doc_id: 984655 cord_uid: 9cxm7j3n nan A 38-year-old man presented with dyspnoea and myalgia. Examination revealed tachycardia at 115 beats per minute and oxygen saturation (SpO 2 ) of 88% on room air. He had lower extremity muscle weakness. Motor testing revealed a bilateral ankle plantarflexion deficit graded at 3/5 on the Medical Research Council muscle scale. All nerve reflexes were normal. The patient's medical history was unremarkable. On admission, blood work-up revealed creatine kinase (CK) of 19.250 IU/L (n<195 IU/L), C reactive protein (CRP) of 72 mg/L (n<5 mg/L), D-dimer of 1430 ng/ mL and lymphocytopenia. CT of the lung revealed bilateral ground-glass opacities (figure 1A). PCR testing for SARS-CoV-2 was positive. The results of influenza PCR were negative. A distal lower limb MRI showed bilateral gastrocnemius oedema, compatible with bilateral myositis (figure 1B). All immunological tests looking for any forms of myositis were negative. The diagnosis of COVID-19-associated myositis and pneumonitis was established, and a 5-day course of 1000 mg intravenous methylprednisolone, hydroxychloroquine and favipiravir was started. Over 5 days, his CK and CRP levels normalised. On day 10, a clear improvement in the patient's general condition was observed, with an SpO 2 of 97% without any need for supplemental oxygen. Viral infections such as influenza A and B are well-known causes of myositis. 1 A study performed in patients with COVID-19 reported that about 13.7% of these patients had elevated CK levels. Muscle weakness related to COVID-19 has been reported in two patients with the MRI documentation of such myositis. 2 3 We present an extremely rare case diagnosed with COVID-19-associated myositis. Twitter Sadettin Uslu @sadouslu Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors. Bacterial, fungal, parasitic, and viral myositis Myositis as a manifestation of SARS-CoV-2 COVID-19-associated myositis with severe proximal and bulbar weakness Patient consent for publication Not required.Provenance and peer review Not commissioned; internally peer reviewed.This article is made freely available for use in accordance with BMJ's website terms and conditions for the duration of the covid-19 pandemic or until otherwise determined by BMJ. You may use, download and print the article for any lawful, non-commercial purpose (including text and data mining) provided that all copyright notices and trade marks are retained. Sadettin Uslu http:// orcid. org/ 0000-0001-6266-2454