Evaluation of two stool antigen tests for the detection of Helicobacter pylori infection in the Chinese population.
OBJECTIVE
The stool antigen test, the HpSA test, has been validated mainly in Western countries, but not properly in the Chinese population. Recently, another stool antigen test, the Apollo test, was developed, but its accuracy has rarely been validated. The aim of this study is to compare the accuracy of these two tests in the diagnosis of Helicobacter pylori infection in the Chinese population.


METHODS
Consecutive dyspeptic patients referred for upper endoscopy were recruited. During endoscopy, biopsies were taken for the rapid urease test and histological examination as the gold standard. Stool specimens were collected and used for the HpSA and Apollo tests.


RESULTS
Overall, 86 patients (39 males and 47 females, with a mean age of 55.8 years) were recruited. Helicobacter pylori infection was present in 44 (51%) patients as determined by the gold standard. The sensitivity, specificity and accuracy were 86.4, 100, and 93.0%, respectively, for the HpSA, and 90.9, 97.6, and 94.2%, respectively, for the Apollo test when cases with equivocal results were considered as positive. In addition, agreement was achieved in 81 (94.2%) cases between the two tests, with a Kappa value of 0.887.


CONCLUSIONS
Both the HpSA and Apollo tests achieve acceptable sensitivity and excellent specificity, with accuracies of over 90% for the detection of H. pylori infection in the Chinese population.
Wong
Benjamin Chun Yu
BC
Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong S.A.R, China. bcywong@hku.hk
Xia
Harry Hua Xiang
HH
Cheung
Hess Kwan Lok
HK
Ng
Fook Hong
FH
Wong
Siu Yin
SY
Chow
Kai Chiu
KC
Lin
Shao Kai
SK
Yin
Yan
Y
Wong
Wai Man
WM
Yuen
Man Fung
MF
Lam
Shiu Kum
SK
D000368:Aged; D000942:Antigens, Bacterial / Q000302:isolation & purification*; D044466:Asian People; D005243:Feces / Q000382:microbiology*; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000208:ethnology*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged
D000942:Antigens, Bacterial