Cardiac sarcoidosis requiring ICD placement and immune thrombocytopenia following alemtuzumab treatment for multiple sclerosis.

Alemtuzumab, an effective disease-modifying therapy for multiple sclerosis, carries a significant risk of secondary autoimmunity. We present a case of cardiac sarcoidosis and immune thrombocytopenia diagnosed in an MS patient two years after completing alemtuzumab treatment. We hypothesize that alemtuzumab-induced changes to the T regulatory cell population may be implicated in the development of sarcoidosis in MS patients.