Stool immunoassay for Helicobacter pylori is not specific enoughBMJ 2000; 320 doi: https://doi.org/10.1136/bmj.320.7248.1541 (Published 03 June 2000) Cite this as: BMJ 2000;320:1541
All rapid responses
I thank Mario Guslandi who is a very good friend of mine, for his comments
on our evaluation of the stool immunoassay for Helicobacter pylori (BMJ
2000; 320: 1541, 3 June). There appears agreement that HpSA is highly
accurate in untreated patients. On the other hand, the case at issue
concerns its value as a test of successful bacterial eradication.
Sometimes I do really think it is better to wait that full papers are
available before making comments, positive or negative, on the basis of
abstracts which, after two years have not been published anywhere! (1,2).
Moreover, three more full papers have been recently published. All of them
are supporting our findings (3-5).
Anyhow, I do think that we (myself as well as Guslandi) should rely on
objectivity for new tests as well as for new drugs. Our goal is to help
anyone who is not deeply involved in this field to understand if something
is good or not. At this point a strong help comes from a statistician, who
usually only cares to give an objective evidence which must be valid for
everyone. That is what we have done in the table below mentioning all
"full papers" so far available on therapy follow-up (3-8), putting
together the good and the bad results and asking the statistician to
calculate the weighted mean. What else can we do for our readers?
Table: Post-treatment diagnostic accuracy of HpSA _______________________________________________________ Reference Patients N = 633 Sens (%) Spec (%) _______________________________________________________ Braden (3) Germany 115 91.3 94.6 Vaira (4) Europe 235 93.8 96.9 Ishihara (5) Japan 112 89 98 Makristhatis (6) Austria 55 85.7 68.3 Trevisani (7) Italy 116 93 82 Weighted Mean 92 92.2 _______________________________________________________
Dino Vaira, 1st Medical Clinic, University of Bologna, S. Orsola
Hospital, Bologna 40138, Italy
1. Masoero G. Lombardo L, Della Monica P. et al. Discrepancy between
Helicobacter pylori stool antigen assay and urea breath test in the
detection of Helicobacter pylori infection. Gut 1999; 45: A131(abstract).
2. Forne' M, Lite J, Dominguez J, Esteve M, et al. Accuracy of a non-
invasive immunoassay for detection of H pylori antigen in stools in the
diagnosis of infection and follow-up after eradication. Gut 1999; 45:
3. Braden B, Teuber G, Dietrich CF et al. Comparison of new faecal antigen
test with 13C-urea breath test for detecting Helicobacter pylori infection
and monitoring eradication treatment: prospective clinical evaluation. BMJ
2000; 320: 148.
4. Vaira D, Malfertheiner P, Mégraud F, et al. Non invasive antigen based
assay for assessing Helicobacter pylori eradication. A European
multicentre study. American Journal of Gastroenterology 2000; 95: 925-29.
5. Ishihara S, Kaji T, Kawamura A, et al. Diagnostic accuracy of a new non
-invasive enzyme immunoassay for detecting Helicobacter pylori in stools
after eradication therapy. Aliment Pharmacol Ther 2000; 14: 611-14.
6. Makristathis A, Pasching E, Schùtze K, et al. Detection of Helicobacter
pylori in stool specimens by PCR and Antigen Enzyme Immunoassay. J Clin
Microbiol 1998; 36: 2772-74
7. Trevisani L, Sartori S, Galvani F, et al. Evaluation of a new enzyme
immunoassay for detecting Helicobacter pylori in faeces; a prospective
pilot study. Am J Gastroenterol 1999; 94: 1831-33.
8. Plebani M, Basso D. Diagnosis of Helicobacter pylori infection by HpSA
test. Lancet 1999; ii: 1209.
Competing interests: Table: Post-treatment diagnostic accuracy of HpSA_______________________________________________________Reference Patients N = 633 Sens (%) Spec (%)_______________________________________________________Braden (3) Germany 115 91.3 94.6Vaira (4) Europe 235 93.8 96.9Ishihara (5) Japan 112 89 98Makristhatis (6) Austria 55 85.7 68.3Trevisani (7) Italy 116 93 82Weighted Mean 92 92.2_______________________________________________________