Tehreem fatima, Muhammad Salman Mushtaq, Hassan Mumtaz, Mohmmmad Owais, Babar Salim, Saba Samreen.
Polymyositis is the chronic inflammation of the muscles, mostly involving the proximal musculature. Myasthenia Gravis is characterized by fluctuating muscle weakness, with improvement of strength after rest. Juvenile Myasthenia Gravis presents before the age of 18. Polymyositis and Myasthenia gravis rarely exist together. Only few cases of this association have been reported so far in adults, while only one such case has been reported in adolescents. We present a 13-year-old patient with 2-year history of proximal muscle weakness and easy fatigability with bilateral ptosis since childhood. Clinical features, examination, laboratory findings, Electromyography (EMG), muscle biopsy and acetylcholine receptor antibodies of patient were in favor of the overlap. The patient improved clinically with pyridostigmine, prednisolone and methotrexate.