The role of serum KL-6 measurement in common pediatric respiratory infections

J Infect Chemother. 2006 Feb;12(1):22-4. doi: 10.1007/s10156-005-0416-9.


KL-6 is a useful marker for interstitial pneumonia of various origins. However, the role of KL-6 in common pediatric respiratory infections is largely unknown. In order to determine whether the KL-6 level is elevated during respiratory infection, and whether KL-6 is a useful biomarker for the disease activity, we evaluated serum KL-6 levels in 132 children with various respiratory infections. KL-6 levels were significantly higher in patients with measles, influenza, or respiratory syncytial virus infection than in the control subjects. On the other hand, KL-6 levels in patients with bacterial infections such as mycoplasma, chlamydia, or pertussis were comparable to the control values. In patients with viral infections, high KL-6 levels, as defined by the mean plus 2 standard deviations of the control group, significantly correlated with low SpO(2) or days of O(2) administration, but did not correlate with C-reactive protein or white blood cell counts. These results indicate that measurement of serum KL-6 levels is helpful for the management of common pediatric respiratory infections.

MeSH terms

  • Adolescent
  • Antigens, Neoplasm
  • Biomarkers / blood
  • C-Reactive Protein / analysis
  • Case-Control Studies
  • Child
  • Child, Preschool
  • Humans
  • Infant
  • Influenza, Human / blood
  • Influenza, Human / diagnosis
  • Leukocyte Count
  • Measles / blood
  • Measles / diagnosis
  • Mucin-1
  • Mucins / blood*
  • Oxygen / metabolism
  • Prospective Studies
  • Respiratory Syncytial Virus Infections / blood
  • Respiratory Syncytial Virus Infections / diagnosis
  • Respiratory Tract Infections / blood*
  • Respiratory Tract Infections / diagnosis
  • Sensitivity and Specificity


  • Antigens, Neoplasm
  • Biomarkers
  • MUC1 protein, human
  • Mucin-1
  • Mucins
  • C-Reactive Protein
  • Oxygen