title: Helicobacter pylori and upper gastrointestinal symptoms in bronchiectasis.
abstract: The recently reported increase in seroprevalence of Helicobacter pylori, the causative pathogen in peptic ulceration, in bronchiectasis is unexplained. Therefore, the association of antibodies directed against cytotoxin-associated gene A(CagA), whose expression indicates virulence of H. pylori, and upper gastrointestinal symptoms in patients with stable bronchiectasis and healthy volunteers evaluated. One hundred patients (mean +/- SD age 55.1+/-16.7 yrs) and 94 healthy asymptomatic subjects (54.6+/-7.6 yrs) underwent clinical and physiological assessment and serum levels of anti-H. pylori CagA were determined using standard clinical and enzyme-linked immunosorbent assay techniques. Samples were positive for anti-H. pylori CagA in 11.7% of controls and 24% of bronchiectatic subjects (p = 0.03). There was, however, no association between serum H. pylori CagA immunoglobulin G level and forced expiratory volume in one second (FEV1), forced vital capacity (FVC), sputum volume, respiratory symptoms or upper respiratory gastrointestinal symptoms (p>0.05). Patients who suffered from acid regurgitation or upper abdominal distension had significantly lower FEV1 and FVC (as a percentage of the predicted value) compared to their counterparts. The results of anticytotoxin-associated gene A measurements in this study contrasted with the previous finding that anti-Helicobacter pylori immunoglobulin G correlated with sputum volume. These findings, therefore, suggest that Helicobacter pylori, should it have a pathogenic role in bronchiectasis, could act via noncytotoxin-associated gene A-mediated mechanisms, and, in this context, gastro-oesophageal reflux might be of importance in bronchiectasis.
authors.affiliation: University Dept of Medicine, The University of Hong Kong, Queen Mary Hospital, SAR.
authors.forename: K W
authors.initials: KW
authors.lastname: Tsang
authors.forename: W K
authors.initials: WK
authors.lastname: Lam
authors.forename: E
authors.initials: E
authors.lastname: Kwok
authors.forename: K N
authors.initials: KN
authors.lastname: Chan
authors.forename: W H
authors.initials: WH
authors.lastname: Hu
authors.forename: G C
authors.initials: GC
authors.lastname: Ooi
authors.forename: L
authors.initials: L
authors.lastname: Zheng
authors.forename: B C
authors.initials: BC
authors.lastname: Wong
authors.forename: S K
authors.initials: SK
authors.lastname: Lam
mesh_terms: D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial; D001426:Bacterial Proteins / Q000032:analysis*; D001987:Bronchiectasis / Q000150:complications* / Q000175:diagnosis; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D005767:Gastrointestinal Diseases / Q000175:diagnosis / Q000209:etiology*; D005798:Genes, Bacterial; D016481:Helicobacter Infections / Q000175:diagnosis / Q000209:etiology*; D016480:Helicobacter pylori / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012129:Respiratory Function Tests; D018709:Statistics, Nonparametric
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C080866:cagA protein, Helicobacter pylori