title: [Neopterin as marker of immunologic activation in viral and bacterial infections].
abstract: OBJECTIVE
  Neopterin is released mainly by macrophages during immune system activation. Therefore, the production of neopterin should be increased by infections and its levels in blood and urine are perhaps in relation to the type of infection.
  
  
  METHODS
  Neopterin levels in urine were determined in 194 healthy children to obtain normal values. Levels of neopterin were also studied in 91 children with viral and 41 with bacterial infections by using high performance liquid chromatography (HPLC). The results are expressed by means of the neopterin/creatinine quotient (neopterin factor = NF).
  
  
  RESULTS
  NF significantly increased in 95.6% of the viral infections (sensitivity of 95.6% and specificity of 92.7%) and in 40.4% of the bacterial infections (sensitivity of 40.4% and specificity of 92.7%).
  
  
  CONCLUSIONS
  NF rises more frequently in viral than in bacterial infections, reaching higher levels earlier in the former.
authors.affiliation: Departamento de Pediatría, Hospital Doce de Octubro, Madrid.
authors.forename: A
authors.initials: A
authors.lastname: Panero López
authors.forename: A
authors.initials: A
authors.lastname: Nogales Espert
mesh_terms: D000293:Adolescent; D001424:Bacterial Infections / Q000276:immunology / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D001708:Biopterins / Q000031:analogs & derivatives* / Q000652:urine; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D019798:Neopterin; D012680:Sensitivity and Specificity; D014777:Virus Diseases / Q000276:immunology / Q000652:urine*
chemical_list: D015415:Biomarkers; D001708:Biopterins; D019798:Neopterin