Rheumatoid myositis: An unusual presentation of rheumatoid arthritis maquerading as an inflammatory myopathy
Alagoma Iyagba, Dasetima Altraide
A 55 year old presented with a seven month history of gradual and progressive weakness of all limbs marked proximally that started at about the same time. No preceding history of fever. However she noticed swelling of both wrists at the onset of symptoms.Examination revealed symmetrical wasting of all limbs with power of 3/5 globally. There was global diminution of her reflexes. Other systems were normal.Creatinine phosphokinase was markedly elevated at 2,550 U/L (26-140). Rheumatoid factor was also significantly elevated-1540.0 IU/ml (0-20.0). Antinuclear antibodies (ANA) was strongly positive at 16.0 U (<0.7-1.0); anti-double stranded DNA (dsDNA)-1.0 IU/ml (<10). Serum aldolase was 0.8 U/L (1.5-8.1). HIV was seronegative. She declined muscle biopsy. Full blood count was basically normal except for raised erythrocyte sedimentation rate of 60 mm/hr. She was commenced on oral prednisolone 60 mg daily with physiotherapy and had full recovery of muscle function after 4 weeks.