Eosinophilic polymyositis M33.9

Eosinophilic polymyositis is one of many manifestations of the hypereosinophilia syndrome (HES). By definition, this is an idiopathic multisystem inflammatory disease characterized by blood eosinophilia (> 1,500/µl) for at least 6 months and multiple eosinophilic organ infiltrations and organ dysfunction.

Muscle biopsy reveals a pattern similar to PM, with eosinophilic granulocytes predominating in the inflammatory infiltrate.

Characteristic features are blood eosinophilia and an increase in muscular serum enzymes and ESR. Occasionally, rheumatoid factors can also be detected.

Glucocorticoids in a dosage of initially 1mg/kgKG are the first choice. In case of insufficient efficacy, various immunosuppressive therapeutics are used.

The prognosis is serious despite adequate therapy: the median survival is reported in the literature to be 9 months; on average 12% of patients live longer than 3 years.