Case report
A 59-year-old man was referred to our hospital for generalized myalgia. Approximately 2 years ago, he had been hospitalized for COVID-19, and 6 months after recovering from COVID-19, he began to notice generalized muscle pain and fatigue. He was subsequently referred to local clinics, where blood tests and imaging studies were performed, including magnetic resonance imaging and computed tomography. However, no abnormal findings were observed. This was the case at several medical facilities visited by the patient, with one doctor advising that he exercise. The patient’s symptoms further exacerbated, prompting his visit to our hospital. Although we performed a variety of tests to identify all possible causes of myalgia, we found no obvious anomalies (Table 1). Physical examination revealed no second wind phenomenon or muscle hypertrophy or atrophy, and his score on the Medical Research Council Scale was normal, with no evidence of myopathy. After excluding all possible causes, we recalled the history-taking interview in which the patient expressed a concern about PEM, a symptom that has been suggested in the literature as consistent with ME/CFS. Given previously published reports of atypical serum acylcarnitine profiles in ME/CFS, we sought additional bloodwork and found the patient to have decreased levels (Table 2). Subsequently, we found that all of the criteria were met for a diagnosis of ME/CFS (Table 3) (7), leading to a confirmed diagnosis, at which point the patient was referred to a specialized facility to pursue epipharyngeal abrasive therapy for its anti-inflammatory effects.