Co-existent ocular myasthenia gravis and Graves’ disease in a 5 year old

Myasthenia gravis and Graves’ disease are known to co-exist in adults, yet there have only been a small number of paediatric cases reported. We report a 5 year old female who was diagnosed with ocular myasthenia gravis after presenting with unilateral ptosis and subsequently found also to have Graves’ disease. She was treated successfully with pyridostigmine, corticosteroids and carbimazole without symptom recurrence or progression to generalised myasthenia gravis. The aetiology of the coexistence is not fully understood, nor is the relationship between the two disorders’ presentation and treatment. We discuss the variation in clinical presentation of myasthenia gravis between populations and when associated with autoimmune thyroid disease, potential HLA-related genetic susceptibility and the varying approaches to treatment of the co-existent disorders