INFLUENCE OF EXOCRINE PANCREATIC INSUFFICIENCY ON THE INTRALUMINAL PH OF THE PROXIMAL SMALL-INTESTINE

The effect of significant exocrine pancreatic disease on the intraluminal pH in the upper small intestine was studied in seven patients with pancreatic insufficiency (PI) and seven control subjects. A cecar microelectrode (Beckman) attached to a polyvinyl tube was positioned at the ligament of Treitz under fluoroscopic control and the output of the pH meter was recorded for 30 minutes under fasting conditions after an equilibration period. Analysis of the pH tracing revealed a significantly lower mean intraluminal pH in PI patients as compared to the control subjects (PI vs controls: mean±sem, 6.1±0.2 vs 7.0 ±0.2, P<0.01). The acid fluctuations per ten-minute period of time were more frequent and the percent time below pH 4.0 was significantly higher in this group of patients (P< 0.05). The basal and the stimulated gastric acid outputs were lower in PI patients. However, the difference did not reach statistical significance. In two PI patients and two control subjects, the intraluminal pH at the duodenojejunal junction was further recorded for 180 minutes after the ingestion of a standardized test meal. Intraluminal pH dropped below 4.0 in both PI patients and continued in that range until the end of the study. However, in the two control subjects, the intraluminal pH stayed well above pH 4.0 during the entire postprandial period. Furthermore, a definite rise with a trend towards the fasting intraluminal pH was also observed. These data indicate that patients with significant exocrine pancreatic disease have an acidic milieu in the upper small intestine both under fasting as well as under postprandial conditions. The clinical relevance of this observation is discussed. © 1979 Digestive Disease Systems, Inc.