Plasma levels of gastric biomarkers in patients after bariatric surgery: biomarkers after bariatric surgery.

Background/Aims: To investigate the profile of stomach specific biomarkers in blood plasma after bariatric surgery Methodology: The study included 20 laparoscopic gastric bypass. (LGBP) and: 20 laparoscopic gastric sleeve (LGS) patients operated on average 22 months earlier. The biomarkers were fasting plasma level of pepsinogen I (PGI), pepsinogen II (PGII), PGI/PGII ratio, fasting and stimulated levels of amidated gastrin-17 (G17), and Helicobacter pylori antibodies (IgG). Results: The prevalence of cases With abnormally low PGI (levels <30 mu g/L, seen typically in advanced atrophy of the gastric corpus mucosa, were 80 % and 40% in LGS and the LGBP groups, respectively (p=0.013). Mean fasting G17 was normal, 3.1 +/- 4.3 pmol/L, in the LGBP patients but high, 13.9 +/- 17.2 pmol/L, in the LGS patients (p = 0.01), the levels exceeding the upper normal cut-off limit (7 pmol/L) in 40% of the LGS patients. The stimulated levels of G17 were normal (>3 pmol/L after a protein rich drink) in all LGS patients, suggesting that the antral G cells functioned normally. Conclusions: Plasma PGI tends to be low in patients after bariatric surgery, in particular after LGS. "Sleeve" resection results in impairments in the secretory functions of the gastric corpus and fundus but leaves the antral functions intact.