Identification of Helicobacter spp. in bile and gallbladder tissue of patients with symptomatic gallbladder disease

Abstract

Background: This experimental study was designed to determine if Helicobacter spp. contribute to benign gallbladder disease using polymerase chain reaction (PCR) methods.

Methods: Patients with benign gallbladder disease scheduled for elective cholecystectomy at New York University Langone Medical Center were recruited from February to May 2008. Bile, gallbladder tissue and gallstones were collected. DNA was isolated from these specimens and amplified via PCR using C97F and C98R primers specific for Helicobacter spp. Appropriate positive and negative controls were used. Products were analysed with agarose gel electrophoresis, sequenced and results aligned using sequencher. Plasma was collected for detection of anti-Helicobacter pylori antibodies via enzyme-linked immunosorbent assay.

Results: Of 36 patients, 12 patients' bile and/or tissue were positive for Helicobacter spp. by PCR. Species were most homologous with H. pylori, although other Helicobacter spp. were suggested. Six of 12 patients demonstrated anti-Helicobacter antibodies in plasma, suggesting that the remaining six might have demonstrated other species besides H. pylori. Four of six plasma samples with anti-Helicobacter antibodies were anti-CagA (cytotoxin associated gene) negative.

Discussion: Helicobacter spp. can be detected in bile and gallbladder tissue of patients with benign gallbladder disease. The contribution of these bacteria to the pathophysiology of gallbladder disease and gallstone formation requires further study.

Figure 1

Representative gel of bile samples after polymerase chain reaction (PCR) amplification using Helicobacter-specific primers C97F and C98R. Four water samples were used as a negative control; HP26, a known Helicobacter pylori sample, was used in duplicate as a positive control. In this gel, A, B, F and G were all considered positive and I was considered indeterminate. G and I were considered negative upon repeated PCR experiments. All other samples were considered negative for Helicobacter spp.