A 7-year-old boy with a two-year history of acute lymphoblastic leukemia was hospitalized for evaluation of fever, malaise, cough, rash, and dyspnea. His leukemia was believed to be in remission while he was on maintenance therapy of prednisone and methotrexate.
The present illness started four days prior to admission with fever, malaise, and erythematous rash initially on the face but later extending to the neck and trunk. There was a questionable history of measles one year previously. On physical examination he was an acutely ill dyspneic child with tachycardia, tachypnea, a temperature of 39 °C, and an erythematous maculopapular rash. No Koplik spots were seen. Diffuse rales over both lungs were heard. A chest roentgenogram (Fig 1) was obtained. Arterial blood gas levels were Po2, 58 mm Hg, Pco2, 28 mm Hg, and pH, 7.45.
His condition did not improve over 24 hours while receiving antibiotics and O