Inclusion body myositis

Weakness is often asymmetrical in contrast to polymyositis. Fatigue and exercise intolerance are common but not with shortness of breath and the respiratory muscles are usually spared. Dysphagia is problematic in 40-50% of patients. Limb weakness is not inevitable and weakness of erector spinae and 'droopy neck' can be the presentation. Muscle pain and cramps are uncommon but may occur. Sensory or autonomic changes only tend to occur if there is also a concurrent polyneuropathy, such as may occur with diabetes.