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 TABLE 101.9 COMPLICATIONS OF JUVENILE DERMATOMYOSITIS Clinical entity Symptoms and signs Investigations Treatment Respiratory failure Air hunger, tachypnea, cyanosis, shallow respiration, alteration in mental status Chest radiograph Arterial blood gas Pneumothorax Chest pain Breathlessness, tachypnea, cyanosis, diminished breath sounds, increased resonance to percussion Chest radiograph Oxygen Mechanical ventilatory support Corticosteroids and immunosuppressives, plasmapheresis Antibiotics if evidence of aspiration pneumonia Chest tube Velopalatine weakness Pooling of secretions, drooling Nasal voice Aspiration pneumonia— recurrent Abdominal pain, nausea, vomiting Guarding, diminished bowel sounds (may be masked by corticosteroids) Hematemesis, melena, hematochezia Careful barium Corticosteroids cineradiographic Nasogastric feedings study Tracheostomy Chest radiograph Gastrointestinal hemorrhage CBC; type and cross Abdominal radiograph: flat plate and upright Endoscopy Angiography Nuclear scan NPO, NG tube Support of circulatory volume Antacids Corticosteroids Surgical consult Interventional radiology Gastrointestinal perforation May be silent Abdominal NPO, NG tube (corticosteroids) radiographs: flat Surgical consult or associated plate and upright with abdominal pain, distention, vomiting Calcinosis Swelling CBC resembling Radiograph cellulitis around Aspiration large joints Fever Antibiotics if superinfection suspected Pain control Carditis Dyspnea, tachycardia, arrhythmias Digoxin, diuretics Antiarrhythmics Corticosteroids Chest radiograph EKG Echocardiogram CBC, complete blood count; NPO, nothing by mouth; NG, nasogastric; EKG, electrocardiogram If pulmonary problems are suspected to result from infection, treatment with IV antibiotics should be initiated after appropriate cultures are obtained It should be noted that patients with JDM may have persistent lymphopenia, especially those treated with chronic or high-dose corticosteroids, that places them at risk for opportunistic infections, like pneumocystis, for which prophylactic antibiotics are indicated In addition, sufficient corticosteroids (three times physiologic need) are given to compensate for potential iatrogenic adrenal insufficiency if the child has recently received high doses of steroids Pneumothorax is another complication of JDM GI Complications Vasculitic changes, characterized by intimal hyperplasia and arteriolar occlusion by fibrin thrombi, are characteristic of severe or poorly controlled JDM Arteries and veins of the skin, muscles, and GI tract may be involved Resultant ulcerations and perforations may occur anywhere from the esophagus to the large intestine, and they may disrupt the integrity of the integument Symptoms and signs of these complications depend on the site of the lesion GI hemorrhage in JDM presents similarly to GI bleeding from other causes, and its evaluation and management are routine The details of the management of hemorrhage from the GI tract are discussed in Chapter 33 Gastrointestinal Bleeding In a patient with JDM, intestinal perforation may go unnoticed because of corticosteroid therapy and may present with pneumatosis intestinalis This finding also may precede clinical perforation and pneumoperitoneum Thus, any patient with JDM and persistent abdominal pain should be examined radiographically for the presence of gas in the bowel wall