title: Evaluation of stool antigen test, PCR on ORAL samples and serology for the noninvasive detection of Helicobacter pylori infection in children.
abstract: BACKGROUND
  Endoscopy represents the gold standard for the diagnosis of Helicobacter pylori infection. We evaluated three noninvasive tests in a group of children: the immunoassay for detection of H. pylori stool antigen, the polimerase chain reaction for identification of bacterial DNA on the oral cavity and the serum specific antibodies.
  
  
  METHODS
  One hundred and ninety children underwent endoscopy for various gastrointestinal symptoms. H. pylori stool antigen and anti-H. pylori antibodies were assayed by commercial kits. The bacterial DNA on saliva and oral plaque was detected by a seminested PCR.
  
  
  RESULTS
  Based on the positivity of culture or urease rapid test and histology, infection was detected in 47 patients. The statistical analysis showed that, for the detection of the infection, stool antigen assay is more effective in sensitivity and negative predictive value (91.5% and 96.5%), whereas specificity and positive predictive values appear slightly better in serology (89.6% and 76.0%). Correlations between serum IgG both with patients' age (r = 0.21, p < .05) and H. pylori stool antigen (r = 0.47, p < .01) were found. The search for bacterial DNA on oral samples proved to be very specific (99.1% on saliva and 98.2% on plaque), but insensitive (22.2% and 25.7%). CONCLUSIONS. In children H. pylori stool antigen represents a sensitive test, suitable for detecting H. pylori infection. Serum IgG proved to be more specific; the PCR on the oral cavity resulted as being a very specific, but insensitive test.
authors.affiliation: Istituto di Clinica Pediatrica, Università di Roma 'La Sapienza', Roma, Italy.
authors.forename: Margherita
authors.initials: M
authors.lastname: Bonamico
authors.forename: Pier Michele
authors.initials: PM
authors.lastname: Strappini
authors.forename: Enea
authors.initials: E
authors.lastname: Bonci
authors.forename: Mirella
authors.initials: M
authors.lastname: Ferri
authors.forename: Massimo
authors.initials: M
authors.lastname: Crisogianni
authors.forename: Mirka
authors.initials: M
authors.lastname: Guido
authors.forename: Enina
authors.initials: E
authors.lastname: Thanasi
authors.forename: Raffaella
authors.initials: R
authors.lastname: Nenna
authors.forename: Stefania
authors.initials: S
authors.lastname: Macchia
authors.forename: Ida
authors.initials: I
authors.lastname: Luzzi
authors.forename: Fabio Massimo
authors.initials: FM
authors.lastname: Magliocca
authors.forename: Paola
authors.initials: P
authors.lastname: Mastromarino
mesh_terms: D000293:Adolescent; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000032:analysis; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005260:Female; D005753:Gastric Mucosa / Q000382:microbiology; D005773:Gastroscopy; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology*; D016480:Helicobacter pylori / Q000276:immunology / Q000302:isolation & purification; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007223:Infant; D008297:Male; D016133:Polymerase Chain Reaction; D011933:Reagent Kits, Diagnostic; D012463:Saliva / Q000382:microbiology; D012680:Sensitivity and Specificity; D014510:Urease / Q000032:analysis / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D004269:DNA, Bacterial; D007074:Immunoglobulin G; D011933:Reagent Kits, Diagnostic; D014510:Urease