Comparison of a monoclonal with a polyclonal antibody-based enzyme immunoassay stool test in diagnosing Helicobacter pylori infection before and after eradication therapy.
BACKGROUND
Detection of Helicobacter pylori antigen in stool samples has been a subject of controversy. However, it has been included in several clinical guidelines as a recommended non-invasive testing procedure in dyspeptic patients.


OBJECTIVE
To compare a monoclonal enzyme immunoassay for detection of H. pylori stool antigen (Amplified IDEIA HpStAR, DakoCytomation) with a polyclonal enzyme immunoassay (HpSA test, Premier Platinum HpSA, Meridian Diagnostics) in diagnosing infection and in determining H. pylori status after eradication treatment.


METHODS
We evaluated stool samples of 198 patients diagnosed with H. pylori infection and of 41 patients without infection. The results of the monoclonal enzyme immunoassay HpStAR were compared with those of the polyclonal enzyme immunoassay HpSA.


RESULTS
The sensitivity and specificity of HpStAR were 91.9% and 70.7%, while those of HpSA were 89.4% and 80.5%, respectively. In the 126 patients evaluated 6 weeks after eradication therapy, the overall agreement between urea breath test and HpStAR was 90.5% (P = 0.710) and between urea breath test and HpSA was 76.9% (P = 0.410).


CONCLUSIONS
HpStAR is a rapid and easy-to-perform test with similar sensitivity to HpSA in the diagnosis of H. pylori infection, although it had lower specificity. In contrast, HpStAR is more accurate after eradication therapy than HpSA.
Domínguez
J
J
Servei de Microbiologia, Hospital Universitari Germans Trias i Pujol, Badalona, Departament de Genètica i Microbiologia, Universitat Autònoma de Barcelona, Barcelona, Spain. jadoming@ns.hugtip.scs.es
Forné
M
M
Blanco
S
S
Prat
C
C
Galí
N
N
Latorre
I
I
Viver
J M
JM
Ausina
V
V
D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000302:isolation & purification*; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards; D005243:Feces / Q000382:microbiology*; D005260:Female; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000188:drug therapy; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity
D000907:Antibodies, Bacterial