29PMyological evaluation of patients with post-acute COVID-19 syndrome

Abstract

Post-acute COVID-19 syndrome (PACS) is a highly multifaceted condition, mimicking myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) in patients with the most prolonged evolution. Due to the frequency of muscle pain and exertion intolerance, these patients are often suspected of having a muscular disease. Here we present the results of the neuromuscular evaluation of patients with a clinically defined PACS. Twenty-two consecutive PACS patients (17F, 5M; median age 47 yrs) were included. All had at least one Covid-infection, confirmed by PCR, with mild respiratory symptoms, only one having required hospitalization and transfer to intensive care unit at acute stage. After a variable period between weeks to few months, patients developed chronic fatigue (duration > 6 months; n=22, 100%), post-exertional malaise (n=22, 100%), cognitive impairment including short-term memory loss or “brain fog” (n=22, 100%), muscle pain (n=18, 82%). No other specific neuromuscular clinical sign were found. 100% of patients fulfilled diagnostic criteria for ME/CSF: CDC1994/Fukuda, International Consensus Criteria 2011, US Inst Medicine 2015, UK National Institute for health and Care Excellence, 2021. Nineteen (86%) didn’t show any recovery period after the onset of symptoms. ENMG examination was normal, without myogenic pattern; CK levels were normal; and muscle MRI available in five patients did not present any changes including fibro-fatty replacement. Brain 18FDG -PET/MRI showed a pattern of hypometabolism compatible with ME/CSF in half of patients. Muscle biopsy was performed in 3 patients and disclosed mild myopathic features in 2/3. In conclusion, our long-lasting PACS patients with muscular symptoms fulfilled criteria for ME/CSF and may present myopathological changes at muscle biopsy.