The results of a blood test detected acetylcholine receptor (AchR) antibodies. Based on the symptoms your patient is experiencing in conjunction with the histological analysis leads you to diagnose myasthenia gravis from thymoma.

Thymomas are neoplasms derived from thymic epithelial cells that can display skeletal muscle protein epitopes (including acetylcholine receptors, ryanodine receptors, and titin).

Explain how a T-lymphocyte problem from the thymus contributes to antibody production that is targeting muscle seen in myasthenia gravis.

You advise for a thymectomy (complete surgical resection of the thymus). The thoracoscopic operation was successful. Surgical margins were negative and there was no evidence of macroscopic or microscopic capsular invasion. Intravenous infusion of immunoglobulin G (IgG) helped to remove circulating pathogenic antibodies and the patient improved.

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