Abstract
Myasthenia gravis (MG) is a rare, long-term neuromuscular disorder that can affect
individuals of any age. In Japan, the Omicron variant of coronavirus disease 2019
(COVID-19) began spreading in 2022, and many cases of neurological symptoms caused
by the virus have been reported. Although COVID-19 has been reported to exacerbate
MG in adults, there are no reports on the effects of COVID-19 on the MG symptoms of
pediatric patients. We report the case of a 6-year-old girl with a 3-year history
of MG who presented to our hospital with symptom exacerbation after COVID-19 infection.
Four days before admission, she developed fever with a runny nose and cough. Three
days before admission, she developed severe bilateral blepharoptosis and progressive
limb weakness, and 2 days before admission, she was diagnosed with COVID-19 by SARS-CoV-2
antigen test. Physical examination revealed moderate blepharoptosis and mild bilateral
upper and lower limb weakness. We diagnosed her with worsening MG due to COVID-19,
and she was administered 400 mg/kg intravenous immunoglobulin (IVIG) daily for 5 days
with continued oral corticosteroids and tacrolimus. The patient's symptoms improved
promptly after admission and, at discharge 7 days after admission, her symptoms had
significantly improved. During the 1-month outpatient follow-up period, she remained
stable and the anti-acetylcholine receptor (AchR) antibody level was reduced to 14.6 nmol/L
(from 18.5 nmol/L on admission). Our case suggests that COVID-19 exacerbates MG in
both children and adults.
Keywords
anti-acetylcholine receptor - immunoglobulin - MG - SARS-CoV-2 - steroid
