Aim To evaluate the validity of the CLO test in detecting Helicobacter
pylori in patients with gastric operation and to investigate the
relationship of H. pylori with peptic ulcer recurrence in these
patients.
Methods In this prospective study, 110 consecutive patients, the
majority of whom had undergone gastric operation for benign disease (n =
102), were included. Eighty patients (62 males), aged 38-87 years, had
had a gastrectomy (10 Billroth I, 70 Billroth II), and 30 patients (27
males), aged 36-73 years, had had a vagotomy (13 vagotomy plus
gastroenterostomy, 17 vagotomy plus pyloroplasty). H. pylori was sought
on multiple biopsy specimens, using CLO test and histology (modified
Giemsa stain). The sensitivity, specificity, positive predictive value
(PPV) and negative predictive value (NPV) of the CLO test were estimated
using histology as ‘gold standard’.
Results Overall, 21 gastrectomy patients (26%) were ii pylori-positive
by CLO and 25 (31%) were H. pylori-positive by histology. The estimated
sensitivity, specificity, PPV and NPV of the CLO test, using histology
as ‘gold standard’, were 68%, 91%, 77% and 86%, respectively. The
CLO test was positive in 67% of vagotomy patients (20 of 30), while
50% (15 of 30) were H. pylori-positive by histology, The estimated
sensitivity, specificity, PPV and NPV of the CLO test were 87%, 53%,
65% and 80%, respectively. H. pylori prevalence by histology was 50%
in patients with vagotomy and 31% in those with gastrectomy (P =
0.0787). Recurrent ulcers were observed in 8/30 patients (27%) after
vagotomy and in 10/72 patients (14%) after gastrectomy. Recurrent ulcer
was documented in 6/15 H. pylori-positive patients with vagotomy (40%),
and in one of 25 H. pylori-positive patients with gastrectomy (4%).
This difference was significant (Fisher’s exact test, P = 0.007,
relative risk 5.091, 95% CI 0.819-31.64).
Conclusion The CLO test seems to be unreliable in diagnosing H. pylori
in post-surgical stomach. The ii, pylori prevalence is higher, although
not significantly, in vagotomized patients compared with gastrectomized
patients, and in this group is closely related to the presence of
recurrent ulcer. So, at least in this group of patients, it is strongly
recommended to look for and eradicate H. pylori. (C) 2000 Lippincott
Williams & Wilkins