Severe Rhabdomyolysis without Systemic Involvement: A Rare Case of Idiopathic Eosinophilic Polymyositis

Table 3

Proposed criteria for diagnosis for eosinophilic myositis [13].

	Focal eosinophilic myositis^a	Eosinophilic polymyositis^b	Eosinophilic perimyositis^c
Major	(1) Pain and calf swelling (other muscles can be affected); (2) Deep eosinophilic infiltration with muscle fiber invasion and necrosis on muscle biopsy	(1) Proximal weakness affecting limb girdle muscles (may be severe); (2) Widespread deep infiltration of eosinophil into muscles, with eosinophilic cuffing, on histology. Myonecrosis and endomysium inflammation usually +ve. If −ve deposition of MBP should be demonstrated by immunostain	(1) Myalgia, proximal mild weakness; (2) Eosinophilic infiltrate confined to fascia and superficial perimysium, absence of myofiber necrosis
Minor	(1) ↑ CPK and aldolase; (2) MRI or EMG evidence of focal myositis; (3) Absence of systemic illness; (4) Eosinophilia >0.5 × 10^9/L	(1) ↑ CPK and aldolase; (2) Eosinophilia >0.5 × 10^9/L; (3) Systemic illness with frequent cardiac involvement; (4) Steroids are needed	(1) Absence of systemic manifestations; (2) Normal CK and aldolase levels; (3) Eosinophilia >0.5 × 10^9/L
Exclude	DVT, cellulitis, parasitic infection	HES, cell T clonality, DM, vasculitis (CSS), drugs, calpainopathy, parasitic infections	Toxic oil syndrome, myalgia-eosinophilia, exposure to inorganic or organic substances
Treatment	No steroid treatment required. Symptoms resolve spontaneously	Prednisone 0.5–1 mg/kg/day is the treatment of choice	Rarely requires steroid treatment for symptom resolution

2 major or 1 major and 3 minor criteria establish the diagnosis.
^bBoth major criteria or one major and two minor criteria establish the diagnosis.
^cBoth major criteria and major criteria number 2 plus two minor criteria enable the diagnosis.
Permission for reuse in a journal was acquired from Elsevier. The treatment section is an addition to the original table.