Validation of diagnostic tests for Helicobacter pylori with regard to grade of atrophic gastritis and/or intestinal metaplasia.
OBJECTIVE
To evaluate the validity of the biopsy-based tests (histology, culture, and urease test) and serology in detecting current Helicobacter pylori infection against a background of atrophic gastritis (AG) or intestinal metaplasia (IM).


METHODS
Helicobacter pylori infection was diagnosed in 651 subjects, using the predefined gold standard for H. pylori tests. The sensitivity, specificity, and positive and negative predictive values of culture, CLOtest, histology (Giemsa stain), and serology were calculated with regard to the histological grade of AG and IM. The level of serum pepsinogen (PG) I and II was also measured as a marker for the presence of AG.


RESULTS
In the study population (n = 651), sensitivity and specificity, respectively, were as follows: culture, 56.2 and 100%; histology, 93.0 and 94.0%; CLOtest, 80.4 and 96.7%; serology, 96.0 and 67.5%. If the analysis is limited to those without AG or IM (n = 158) or to those younger than 40 years (n = 69), all tests, except for culture, had a sensitivity and specificity >90%. The sensitivity of CLOtest and the specificity of serology markedly decreased with progression of AG and IM, and serology was less specific in the presence of AG, as determined by a PG I/II ratio < or =4.1 (specificity, 83.7% vs 40.7% in PG I/II >4.1 and < or =4.1, respectively).


CONCLUSIONS
Any one of biopsy-based tests or serology was found to be excellent for identifying current H. pylori infection among individuals without AG or IM and/or younger patients (<40 years). However, a combination of at least two tests is necessary in the clinical setting of AG or IM.
Shin
Cheol Min
CM
Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Korea.
Kim
Nayoung
N
Lee
Hye Seung
HS
Lee
Hee Eun
HE
Lee
Sang Hyub
SH
Park
Young Soo
YS
Hwang
Jin Hyuk
JH
Kim
Jin-Wook
JW
Jeong
Sook-Hyang
SH
Lee
Dong Ho
DH
Jung
Hyun Chae
HC
Song
In Sung
IS
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D005757:Gastritis, Atrophic / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007422:Intestines / Q000382:microbiology / Q000473:pathology*; D008297:Male; D008679:Metaplasia / Q000382:microbiology / Q000473:pathology; D008875:Middle Aged; D055815:Young Adult