False positive diagnosis of phaeochromocytoma in a patient with Parkinson's disease receiving levodopa.

Sir: The weakness in polymyositis is usually described as symmetrical and mainly proximal. Bharucha and Morgan-Hughes' mentioned four patients with chronic focal polymyositis, in whom highly selective muscle wasting and weakness remained confined to the forearm flexors, brachio radialis and quadriceps muscles. We would like to report a patient presenting with chronic bulbar palsy. In April, 1983, a 57 year old man presented with a 4 month history of slowly progressive dysphagia. The difficulty was associated with drinking liquids. Some of the liquid escaped through the nose and coughing or choking was frequent while drinking. On examination, his voice was soft and hypernasalised. Voluntary elevation of the palate was incomplete and the gag reflex was weak. The tongue was atrophic without fasciculation. Neck weakness was prominent, with atrophy of the sternocleidomastoid muscles. There was a positive snout reflex but absent jaw jerk. Ocular movements were full and no weakness was observed in the facial muscles and the four extremities. The deep tendon reflexes were hypoactive in the upper limbs and normal in the lower limbs. The serum creatine kinase (CK) was 56 IU/l (normal, 47 to 210). Electromyography showed fibrillation potentials in the sternocleidomastoid muscles but little abnormality in the individual motor units. Muscle biopsy was not performed. Wasting and weakness persisted, confined to the bulbar and neck muscles. The patient was tube-fed but suffered from recurrent aspiration pneumonia between September, 1983 and April, 1986. In 1987, minimal weakness in the deltoid muscles was noted. A biopsy of the left deltoid muscle showed marked variation in muscle fibre size with large collections of inflammatory cells which were mainly interstitial. A small number of regeneration fibres were present. The CK was 57 IU/1. The patient was treated with prednisone 60 mg daily and during the next 3 months there was improvement in swallowing. He became able to drink liquids without nasal regurgitation and aspiration. In polymyositis dysphagia is unusual as the first symptom and prolonged bulbar palsy without limb girdle weakness has rarely been reported.2' Our patient with morphologically proven polymyositis had selective bulbar palsy of 4 years' duration. The symptoms improved following steroid therapy. Ueno et al3 described a remarkably similar patient who had dysphagia of 2 years' duration and showed a good response to steroids. Although CK is useful in diagnosis and the assessment of activity of polymyositis, the enzyme was normal both in our case and the patient described by Ueno et al. Polymyositis is one of the few neuromuscular diseases in which drug therapy is of value. One should therefore be alert to the possibility and be aware of unusual manifestations of the disease. Chronic focal polymyositis should be considered in the differential diagnosis of bulbar palsy.