The CLO test is unreliable in diagnosing H-pylori infection in post-surgical stomach; is there any role of H-pylori in peptic ulcer recurrence?

Aim To evaluate the validity of the CLO test in detecting Helicobacter pylo ri in patients with gastric operation and to investigate the relationship o f H. pylori with peptic ulcer recurrence in these patients. Methods In this prospective study, 110 consecutive patients, the majority o f whom had undergone gastric operation for benign disease (n = 102), were i ncluded. Eighty patients (62 males), aged 38-87 years, had had a gastrectom y (10 Billroth I, 70 Billroth II), and 30 patients (27 males), aged 36-73 y ears, had had a vagotomy (13 vagotomy plus gastroenterostomy, 17 vagotomy p lus pyloroplasty). H. pylori was sought on multiple biopsy specimens, using CLO test and histology (modified Giemsa stain). The sensitivity, specifici ty, 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 C LO and 25 (31%) were H. pylori-positive by histology. The estimated sensiti vity, specificity, PPV and NPV of the CLO test, using histology as 'gold st andard', were 68%, 91%, 77% and 86%, respectively. The CLO test was positiv e in 67% of vagotomy patients (20 of 30), while 50% (15 of 30) were H. pylo ri-positive by histology, The estimated sensitivity, specificity, PPV and N PV of the CLO test were 87%, 53%, 65% and 80%, respectively. H. pylori prev alence 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. Recurre nt 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%). T his difference was significant (Fisher's exact test, P = 0.007, relative ri sk 5.091, 95% CI 0.819-31.64). Conclusion The CLO test seems to be unreliable in diagnosing H. pylori in p ost-surgical stomach. The ii, pylori prevalence is higher, although not sig nificantly, 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 fo r and eradicate H. pylori. (C) 2000 Lippincott Williams & Wilkins.