Evaluation of diagnostic methods for the detection of Helicobacter pylori in gastric biopsy specimens of dyspeptic patients

• Published in: Brazilian journal of microbiology 2012-07, Vol.43 (3), p.903-908
• Main Authors: Ramis, Ivy Bastos, de Moraes, Ernani Pinho, Fernandes, Márcia Silveira, Mendoza-Sassi, Raul, Rodrigues, Obirajara, Juliano, Carlos Renan Varela, Scaini, Carlos James, da Silva, Pedro Eduardo Almeida
• Format: Article
• Language: English
• Subjects: Diagnostic tests; Gastrointestinal diseases; Gram-negative bacteria; Histology; Medical Microbiology; MICROBIOLOGY; Polymerase chain reaction
• ISSN: 1517-8382; 1678-4405; 1678-4405
• DOI: 10.1590/S1517-83822012000300008

Helicobacter pylori infects nearly 50% of the world's population. This microorganism is accepted as the most important agent of gastritis and as a risk factor for peptic ulcer disease and gastric adenocarcinoma. Currently many diagnostic methods exist for detecting H. pylori, however they all have limitations, thus it is recommend a combination of at least two methods. The aim of this study was to evaluate diagnostic methods, such as in-house urease test, culture and Polymerase Chain Reaction (PCR), for the detection of the H. pylori in gastric biopsy specimens of 144 dyspeptic patients, using as gold standard the association between histology and rapid urease test. According to the gold standard used in this study, 48 (33.3%) patients were infected with H. pylori, while 96 (66.7%) were classified as not infected. The in-house urease test and the PCR were the most sensitive methods (100%), followed by culture (85.4%). However, the inhouse urease test and the culture were the most specific (100%), followed by PCR (75%). In conclusion, this study showed that, in comparison with the combination of histology and rapid urease test, the in-house urease test and the PCR presented 100% of sensitivity in the diagnosis of gastric infection by H. pylori, while the in-house urease test and the culture reached 100% of specificity. These finding suggest that the combination of two or more methods may improve the accuracy of the H. pylori detection.