Post-treatment diagnostic accuracy of a new enzyme immunoassay to detect Helicobacter pylori in stools.
BACKGROUND
Helicobacter pylori has attracted increasing attention among gastroenterologists because of its pathogenic potential, stimulating the search for non-invasive diagnostic tests.


OBJECTIVE
In this study the efficacy of a new enzyme immunoassay designed to detect H. pylori antigens in stools (HpSA) was evaluated before and after eradication therapy.


METHODS
HpSA was performed on stool samples collected from 268 patients whose H. pylori status was defined on the basis of concordant results for the (13)C-urea breath test, rapid urease test and histology. The H. pylori-positive patients were treated with a 1-week triple therapy to eradicate the infection. One (T30) and 3 months (T90) after the end of therapy, (13)C-urea breath test and HpSA were repeated in the treated patients.


RESULTS
The overall diagnostic accuracy of HpSA at T30 (83%, 95% confidence interval (CI) 77--89%) was significantly lower in comparison to the values obtained at baseline (94%, 95% CI: 91--97%) and at T90 (97%, 95% CI: 94--99%). No significant difference was found between the diagnostic accuracy of HpSA at baseline and at T90 (P=0.253).


CONCLUSIONS
The present data suggest that HpSA provides a low diagnostic accuracy when used shortly after treatment. It needs a longer period of follow-up (8--12 weeks) to reach a reliability comparable to the (13)C-urea breath test.
Costa
F
F
Department of Internal Medicine, Section of Gastroenterology, University of Pisa, Italy. fcosta@int.med.unipi.it
Mumolo
M G
MG
Bellini
M
M
Romano
M R
MR
Manghetti
M
M
Paci
A
A
Maltinti
G
G
Marchi
S
S
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000897:Anti-Ulcer Agents / Q000627:therapeutic use; D001944:Breath Tests; D002247:Carbon Isotopes; D005243:Feces / Q000382:microbiology; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods / Q000592:standards; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D013997:Time Factors; D014508:Urea / Q000032:analysis
D000897:Anti-Ulcer Agents; D002247:Carbon Isotopes; D014508:Urea