Plasma ghrelin and liquid gastric emptying in children with functional dyspepsia consistent with post-prandial distress syndrome

Background Adult studies indicate a role for ghrelin in functional dyspepsia (FD) mediated through ghrelin's effect on gastric emptying (GE). This study examines the relationship between ghrelin, liquid GE, and pain in children with FD. Methods Thirteen FD patients reporting symptoms consistent with post-prandial distress syndrome (PDS) and 17 healthy controls were enrolled. All participants received a liquid meal containing C-13-sodium acetate. Pain severity, liquid GE utilizing exhaled (CO2)-C-13 from the sodium acetate breath tests (ABT), plasma acyl ghrelin (AG), and des-acyl ghrelin concentrations were measured at specific intervals over 240 min following ingestion. Key Results FD-PDS patients demonstrated lower mean baseline AG (14.8 +/- 9.7 vs 27.2 +/- 14.0 fmol/mL; p = 0.013), AG C-max (24.6 +/- 8.2 vs 40.5 +/- 16.8 fmol/mL; p = 0.007), and AG flux (18.2 +/- 7.8 vs 32.7 +/- 17.3 fmol/mL; p = 0.015) than controls. The time to reach maximum exhaled (CO2)-C-13 concentration (T (max)) was longer in FD patients than controls (47.5 +/- 18.5 vs 35.8 +/- 11.8 min; p = 0.046). Significant relationships between ghrelin analyte ratios and ABT parameters were largely confined to control participants. Conclusions & Inferences FD-PDS in children is associated with lower fasting and maximum AG concentrations, and dampened AG flux. These data suggest a possible role for altered ghrelin physiology in the pathogenesis of PDS.