RESUMEN
An association between multiple sclerosis and autoimmune hepatitis has been described. The latter can also be unmasked or exacerbated by a variety of therapies used in multiple sclerosis, such as beta-Interferon or glatiramer acetate. Two cases of hepatitis occurring after exposure to glatiramer acetate are described here: the first, was possibly due to autoimmune hepatitis, rather than glatiramer acetate induced liver injury, the second was definite autoimmune hepatitis. Both occurred in patients who had already experienced hepatitis exacerbations during previous beta-Interferon treatment. We suggest that glatiramer acetate can unmask hepatitis. Thus, liver enzyme monitoring should be undertaken frequently in those patients with multiple sclerosis receiving glatiramer acetate, with a history of hepatitis during treatment with Interferon beta-1a.