MxA-based recognition of viral illness in febrile children by a whole blood assay

Pediatr Res. 2006 Dec;60(6):770-4. doi: 10.1203/01.pdr.0000246098.65888.5b. Epub 2006 Oct 25.


Febrile children are often given antibiotics empirically and unnecessarily. MxA is a protein induced in peripheral lymphoid cells by type 1 interferons during active viral infection. The ability of a whole blood ELISA assay for MxA to identify children with viral illness was studied in 122 children who presented with acute onset fever and 52 age-matched healthy controls. The febrile children were divided into three groups according to their final diagnoses: etiologically diagnosed viral infection, clinically diagnosed viral infection, and bacterial infection. MxA levels in the bacterial infection group and controls were similar and low (90.9 +/- 69.7 and 76.9 +/- 63.2 ng/mL, respectively). In contrast, mean MxA levels in the two viral infection groups were higher than in both the bacterial and control groups (719.2 +/- 386.4 and 827.0 +/- 651.1, respectively). A receiver operating characteristic analysis showed that the area under the curve of the MxA level was greater than under the curves of both the white blood cell count and the C-reactive protein concentration. Whole blood assay of MxA is a clinically useful tool for diagnosing viral illness in febrile children and should help reduce use of unnecessary antibiotics.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Anti-Bacterial Agents / therapeutic use
  • Biomarkers / blood
  • C-Reactive Protein / metabolism
  • Child
  • Child, Preschool
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Fever / blood*
  • Fever / virology*
  • GTP-Binding Proteins / blood*
  • GTP-Binding Proteins / genetics
  • Gene Expression Regulation
  • Humans
  • Infant
  • Infant, Newborn
  • Leukocyte Count
  • Male
  • Myxovirus Resistance Proteins
  • Virus Diseases / blood*
  • Virus Diseases / complications
  • Virus Diseases / diagnosis*


  • Anti-Bacterial Agents
  • Biomarkers
  • MX1 protein, human
  • Myxovirus Resistance Proteins
  • C-Reactive Protein
  • GTP-Binding Proteins