Effects of Helicobacter pylori infection on gastric emptying rate in patients with non-ulcer dyspepsia

AIM: The pathogenesis of delayed gastric emptying in patients with non-ulcer dyspepsia (NUD) remains unclear. We aimed to examine whether gastric emptying rate in NUD patients was associated with Helicobacter pylori (H pylori) infection and whether it was affected by eradication of the infection. METHODS: Gastric emptying rate of a mixed solid-liquid meal was assessed by the paracetamol absorption method in NUD patients and asymptomatic controls (n=17). H pylori status was assessed by serology and biopsy urease test. H pylori-positive NUD patients (n=23) received 10-day triple eradication therapy. H pylori status was re-assessed by biopsy urease test four weeks later, and if eradication was confirmed, gastric emptying rate was re-evaluated. RESULTS: Thirty-three NUD patients and 17 controls were evaluated. NUD patients had significantly delayed gastric emptying compared with controls. The mean maximum plasma paracetamol concentration divided by body mass (Cmax/BM) was 0.173 and 0.224 mg/L.kg respectively (P=0.02), the mean area under plasma paracetamol concentration-time curve divided by body mass (AUC/BM) was 18.42 and 24.39 mg.min/L.kg respectively (P=0.01). Gastric emptying rate did not differ significantly between H pylori-positive and H pylori-negative NUD patients. The mean Cmax/BM was 0.172 and 0.177 mg/L.kg respectively (P=0.58), the mean AUC/BM was 18.43 and 18.38 mg.min/L.kg respectively (P=0.91). Among 14 NUD patients who were initially H pylori-positive, confirmed eradication of the infection did not significantly alter gastric emptying rate. The mean Cmax/BM was 0.171 and 0.160 mg/L.kg before and after Hp eradication, respectively (P=0.64), the mean AUC/BM was 17.41 and 18.02 mg.min/L.kg before and after eradication, respectively (P=0.93). CONCLUSION: Although gastric emptying is delayed in NUD patients compared with controls, gastric emptying rate is not associated with H pylori status nor it is affected by eradication of the infection.