IN-SITU HYBRIDIZATION FOR HELICOBACTER-PYLORI IN GASTRIC-MUCOSAL BIOPSY SPECIMENS - QUANTITATIVE-EVALUATION OF TEST-PERFORMANCE IN COMPARISON WITH THE CLOTEST AND THIAZINE STAIN
Dm. Barrett et al., IN-SITU HYBRIDIZATION FOR HELICOBACTER-PYLORI IN GASTRIC-MUCOSAL BIOPSY SPECIMENS - QUANTITATIVE-EVALUATION OF TEST-PERFORMANCE IN COMPARISON WITH THE CLOTEST AND THIAZINE STAIN, Journal of clinical laboratory analysis, 11(6), 1997, pp. 374-379
Numerous detection methods for Helicobacter Pylori (H. pylon) have bee
n developed with varying degrees of purported diagnostic utility. We h
ave developed a rapid nonradioactive in situ hybridization (ISH) metho
d for H. pylori detection in paraffin-embedded tissue and assessed its
relative diagnostic performance by receiver operator characteristics
(ROC) in comparison to the thiazine stain and CLOtest. Forty-five pati
ents undergoing endoscopy had antral biopsies and concomitant CLOtest
performed. ISH for H. pylori was done using a 22-base, biotin-labeled
oligonucleotide probe complementary to a portion of H. pylori 16s rRNA
with the following sequence: 5'-GGACATAGGCTGATCTTAGC-3'. ISH using th
is probe was specific for H. pylori with no cross-reactivity with othe
r bacterial or fungal organisms. Receiver operator characteristic anal
ysis was used to assess the diagnostic performance of ISH and thiazine
techniques. ISH and thiazine stains were done on serial sections, rev
iewed independently, and scored on a graded scale from 1-5 based upon
the degree of assurance of H. pylori presence, Diagnostic performance
was assessed in ''expert'' and ''nonexpert'' pathologist groups with t
he CLOtest serving as the invariant test for relative test comparison.
The ISH test performed slightly better (ROC area 0.9) than the thiazi
ne (ROC area 0.8) in the nonexpert population, but equally well in the
''expert'' group (ROC area 0.95, 0.95). ISH followed by routine hemat
oxylin and eosin staining showed detailed mucosal histology with a dra
matic visualization of H. pylori along the surface of the foveolar cel
ls with no evidence of lamina propria invasion. In summary, ISH for H.
pylori is an excellent test that is specific, easily read, and allows
concomitant detailed histologic mucosal examination. (C) 1997 Wiley-L
iss, Inc.