Gastrin, Pepsinogens, and Helicobacter Pylori Evaluation

Fasting blood samples were collected, and serum samples were stored at –20 °C until further use for both groups. Serum gastrin concentrations were measured using the Gastrin RIA Kit II (Dynabot, Tokyo, Japan). Serum PG I and PG II concentrations were determined by radioimmunoassay (Abbott, Tokyo, Japan) for the years 1990 to 1999, chemiluminescent immunoassay (Abbott) from 1999 to 2001, enzyme immunoassay (E-plate test; Eiken, Tokyo, Japan) from 2001 to 2003, and latex agglutination test (L-Z test; Eiken) from 2003 to 2014. PG positivity was defined as serum PG I concentrations of ≤ 70 ng/mL and a PG I/II ratio of ≤ 3.0 [31 –33 (link)]. Serum anti-Hp Abs in the pathology group was determined with the Pyloristat kit (Whittaker Bioproducts, Walkerville, MD, USA) using enzyme-linked immunosorbent assay (ELISA). Serum anti-Hp Abs titers of the endoscopically-evaluated group were evaluated using ELISA (E-plate; Eiken Chemical). The cut-off value for anti-Hp Abs in the endoscopically-evaluated group was 3 U/mL [34 (link), 35 (link)].