title: Measles pneumonitis.
abstract: OBJECTIVE
  To investigate the finding of increased alveolar-arterial (A-a) gradient in adult patients with measles who have normal results on both pulmonary auscultation and chest radiography.
  
  
  METHODS
  Retrospective, descriptive case series.
  
  
  METHODS
  An urban county teaching hospital in southern California.
  
  
  METHODS
  Consecutive adult patients with the clinical diagnosis of measles seen in the emergency department.
  
  
  METHODS
  Patients were considered to have pneumonitis if they had any of the following: ED diagnosis of pneumonia; an A-a gradient of more than 30 mm Hg; one or more infiltrates on chest radiograph.
  
  
  RESULTS
  Seventy-five patients, including 44 men and 31 women (median age, 25 years; 25% to 75% interquartile range [IQR], 20 to 28 years) were seen during the 36-month study period. Forty-three patients (57%; 95% confidence interval [CI], 45% to 69%) had pneumonitis, with a median A-a gradient of 42 mm Hg (IQR, 34 to 48 mm Hg). Twenty-seven of the 43 patients with pneumonitis (63%; CI, 48% to 77%) had both normal pulmonary auscultation findings and normal chest radiographs; this represented 36% of the study population (CI, 25% to 50%). Thirty-eight of the 43 patients with pneumonitis were admitted; one patient was later intubated after respiratory failure developed. Two of the 5 patients with pneumonitis who were sent home were admitted the following day for worsening symptoms. All 75 patients eventually did well.
  
  
  CONCLUSIONS
  A significant percentage of adult patients with measles presenting to an ED with both normal pulmonary auscultation and normal chest radiographs have increased A-a gradients. These patients warrant close follow-up and perhaps hospital admission.
authors.affiliation: Department of Emergency Medicine, Harbor-UCLA Medical Center, Torrance, USA.
authors.forename: P L
authors.initials: PL
authors.lastname: Henneman
authors.forename: D M
authors.initials: DM
authors.lastname: Birnbaumer
authors.forename: C B
authors.initials: CB
authors.lastname: Cairns
mesh_terms: D000328:Adult; D001314:Auscultation; D001784:Blood Gas Analysis; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000378:metabolism* / Q000821:virology; D008297:Male; D008457:Measles / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D008499:Medical Records; D011024:Pneumonia, Viral / Q000097:blood / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D011379:Prognosis; D011650:Pulmonary Alveoli / Q000378:metabolism*; D011653:Pulmonary Diffusing Capacity; D011859:Radiography; D012135:Respiratory Sounds; D012189:Retrospective Studies