[Myositis as a post-acute sequela of COVID-19 disease? : Even in times of the pandemic, muscle biopsies can only be assessed in the context of accurate clinical information].

A case of a patient suffering from COVID-19 with suspected associated myositis is reported, in which the initially limited information about the history and disease course led to difficulties in establishing a reasonable diagnosis. Through inquiry, further data could be collected, so that the diagnosis of an infection-associated thrombotic microangiopathy in the context of a Morganella morganii myositis could be made. This patient study shows that even in times of the omnipresent pandemic and despite the context of a positive COVID-19 test result, differential diagnoses and the integrative clinicopathologic approach in interpreting muscle biopsy findings should not be neglected.