Detection of Helicobacter pylori by phenotypic and genotypic methods.
OBJECTIVE
This research evaluated the utilization of a urease in-house test, culture and molecular method (ureA PCR) as a diagnostic tool for Helicobacter pylori infection. Furthermore, we assessed the presence of the cagA gene in the specimens and in isolated strains that were positive for ureA by PCR positive.


RESULTS
Sensitivity and specificity, respectively, were 100 and 95.8% for the urease in-house test 93.3 and 95.8 for the ureA PCR assay of the specimen and 100 and 100% for the culture. The presence of the cagA gene was observed in eight (53%) ureA-positive samples.


CONCLUSIONS
In this study, we found that the PCR technique has applicability in the study of cagA, and other genes related to the H. pylori pathogen. This method can be applied to samples directly from biopsy or isolated from the bacteria.
Fonseca
Tesiê L
TL
Universidade Federal do Rio Grande, Rio Grande do Sul, Brazil.
Moraes
Ernani P
EP
Juliano
Carlos R
CR
Silva
Ana M
AM
Scaini
Carlos J
CJ
Mendoza-Sassi
Raul A
RA
Silva
Pedro E A
PE
D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001706:Biopsy; D004269:DNA, Bacterial / Q000032:analysis*; D005260:Female; D005773:Gastroscopy; D005838:Genotype; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008828:Microbiological Techniques / Q000706:statistics & numerical data; D008875:Middle Aged; D010641:Phenotype; D016133:Polymerase Chain Reaction / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013270:Stomach / Q000382:microbiology*; D014510:Urease / Q000032:analysis*
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial; C080866:cagA protein, Helicobacter pylori; D014510:Urease
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