Abstract
A boy with ocular type myasthenia gravis was reported. The therapeutic effect of pyridostigmine bromide and corticosteroid was insufficient. However, clinical symptoms disappered rapidly after an influenza A virus infection. On a peripheral lymphocytes subsets analysis, the CD 3, CD 4 and CD 4/CD 45 RA positive lymphocytes increased with the therapy and decreased after the infection. By contrast, CD 19 positive lymphocytes decreased with the therapy and increased after the infection. These results suggested that influenza A may improve the clinical signs of myasthenia gravis, as is the improved case with measles.