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enzymes, weakness, or GI symptoms not rapidly improve, steroid-sparing agents such as methotrexate (0.75 to 1.25 mg/kg/wk), IV immune globulin (2 g/kg/mo), or cyclosporine A (2 to mg/kg/day) are introduced within to weeks In more recalcitrant cases, it may be necessary to add immunosuppressive drugs such as cyclophosphamide or rituximab Under all circumstances, the goal is to rapidly control disease activity while minimizing toxicity from medications Fortunately, active disease generally does not recur if a complete remission can be induced and maintained for to years During the initial evaluation of JDM, it is essential to monitor the function of the palatopharyngeal and respiratory muscles; palatal weakness increases the risk of aspiration Eating only in the upright position, frequent suctioning, or placement of a nasogastric tube may be necessary to avoid aspiration Support of weak muscles, such as wearing a soft neck collar while riding in automobiles, helps minimize the risk of complications until children regain their strength Management of Complications and Emergencies The most serious emergencies in JDM relate to the respiratory and GI tracts ( Table 101.9 ) In addition, complications may occur as a result of therapy with corticosteroids and immunosuppressive agents (e.g., infection and GI hemorrhage) Respiratory Complications (See also Chapters 71 Respiratory Distress and 99 Pulmonary Emergencies ) Respiratory emergencies seen in JDM have diverse etiologies Entities to be considered include (i) aspiration pneumonia secondary to weakness of velopalatine muscles; (ii) atelectasis and pneumonia secondary to difficulty in clearing secretions as respiratory muscles become involved; (iii) respiratory failure secondary to profound involvement of respiratory musculature, including the diaphragm; (iv) progressive interstitial lung disease; and (v) opportunistic infection (tuberculosis, fungi, viruses, or Pneumocystis ) in the immunocompromised host Because fever may also occur with active JDM, it is necessary to differentiate pyrexia caused by infection from that caused by underlying disease In addition to usual care, preliminary investigations should include measurement of muscle enzymes (including CK, aldolase, AST, ALT, and LDH) as well as vWF:Ag Depending on the seriousness of the symptoms and the cooperativeness of the child, pulmonary function studies should be assessed If the etiology of the respiratory deterioration remains in doubt, more sensitive tests of disease activity, including MRI of the thigh muscles, may be necessary to determine whether more aggressive control of the underlying myositis is necessary Corticosteroids are essential for treating weakness of respiratory muscles and interstitial lung disease Plasmapheresis is reserved for children who deteriorate even after pulse steroid therapy