Late onset of autoimmune hepatitis in myasthenia gravis

A 35-year-old caucasian female presented with acute onset bilateral ptosis while driving, followed by weakness of the facial and upper limb muscles. A diagnosis of myasthenia gravis (MG) was made on the basis of clinical examination, and confirmed by electromyography, high titres of anti- acetylcholine receptor antibodies and a positive response to pyridostigmine. She underwent thymectomy and her symptoms resolved. She presented again 16 years later (age 51) with tiredness, jaundice and a biochemical hepatitis. Serological and histopathological investigations were in keeping with autoimmune chronic hepatitis and there was a satisfactory response to oral prednisolone. She was unable to tolerate the conventional high dose steroid induction due to a relapse of her MG but subsequently entered remission with intermediate dose regime of prednisolone. Despite a recognised association between both autoimmune hepatitis (AIH) and MG with other autoimmune diseases, a literature search showed the combination of these two conditions to be extremely rare with only one adequately documented previous report.