title: Diagnostic utility of invasive tests and serology for the diagnosis of Helicobacter pylori infection in different clinical presentations.
abstract: BACKGROUND
  Invasive and noninvasive tests are used for the diagnosis of Helicobacter pylori infection. The aim of this study was to determine the diagnostic utility of rapid urease test (RUT), culture, histology and serology for the diagnosis of H. pylori in patients with different clinical presentations.
  
  
  METHODS
  We studied 527 consecutive patients (mean age, 52.5 years; F:M, 1.3; age range 15-89 years) enrolled at the Hospital Universitario, Universidad Autónoma de Nuevo León. Patients had gastric cancer (GC, 9.1%), non-ulcer dyspepsia (NUD, 81.4%), or peptic ulcer disease (PUD, 9.1%). The infection by H. pylori was determined by histology, rapid urease test, culture, and serology. Patients were determined as infected with H. pylori if at least a) two invasive tests were positive and b) two tests were positive (invasive or non-invasive). Diagnostic utility was calculated for each assay.
  
  
  RESULTS
  Prevalence of infection in the whole studied population was 50.9%. In NUD patients the prevalence was 51.3%, in PUD patients 58.3%, and in GC patients 39.6%. When we used the first diagnostic criteria, for the whole studied population, the RUT was the most reliable test, followed by the culture. Histology had the best sensitivity for the whole studied population and NUD patients and RUT had the best sensitivity value for the GC patients. In the whole studied population, NUD and GC patients, RUT and culture had the best specificity, accuracy and PPV. For PUD patients, serology had the best performance. When we used the second diagnostic criteria, histology and serology had a better performance compared with the results obtained with the first diagnostic criteria.
  
  
  CONCLUSIONS
  Diagnostic utility of the tests varies according to the clinical presentations, which should be considered in the selection of the diagnostic test for the detection of H. pylori.
authors.affiliation: Servicio de Gastroenterología del Hospital Universitario Dr. José Eleuterio González, Monterrey, Nuevo León, Mexico.
authors.forename: Jaime Raúl
authors.initials: JR
authors.lastname: Zúñiga-Noriega
authors.forename: Francisco Javier
authors.initials: FJ
authors.lastname: Bosques-Padilla
authors.forename: Guillermo Ignacio
authors.initials: GI
authors.lastname: Pérez-Pérez
authors.forename: Rolando
authors.initials: R
authors.lastname: Tijerina-Menchaca
authors.forename: Juan Pablo
authors.initials: JP
authors.lastname: Flores-Gutiérrez
authors.forename: Héctor Jesús
authors.initials: HJ
authors.lastname: Maldonado Garza
authors.forename: Elvira
authors.initials: E
authors.lastname: Garza-González
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004415:Dyspepsia / Q000382:microbiology / Q000473:pathology; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000473:pathology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D010437:Peptic Ulcer / Q000382:microbiology / Q000473:pathology; D012698:Serologic Tests; D013274:Stomach Neoplasms / Q000382:microbiology / Q000473:pathology; D014510:Urease
chemical_list: D014510:Urease