ABSTRACT
Background & objectives: Small intestinal bacterial overgrowth (SIBO) due to ileal brake-induced hypomotility may cause tropical sprue (TS). We evaluated effect of infusion of fat or placebo in duodenum randomly in patients with TS and healthy controls on antroduodenal manometry (ADM) and mediators of ileal brake, and duodenocaecal transit time (DCTT). Methods: ADM and DCTT (lactulose hydrogen breath test, HBT) were evaluated with placebo and fat in eight controls and 13 patients with TS (diagnostic criteria: tests showing malabsorption of two unrelated substances, abnormal duodenal histology, absence of other causes, response to antibiotics and folate). Results: Patients with TS (6 had SIBO by glucose HBT) were similar in age and gender with controls. After fat infusion, proximal gut motility index (MI) was reduced compared to fasting state in TS, and DCTT was longer in TS than controls (200 min, 120-380 vs. 130, 70-160, P=0.001), though comparable after placebo (70 min, 30-140 vs. 60, 40-90). TS patients had higher PYY and neurotensin than controls after fat infusion. DCTT after fat infusion correlated with plasma level of PYY in TS but not in controls. Post-fat PYY and neurotensin levels were higher in TS with lower BMI (<16 kg/m2) than those with higher BMI. Parameters of ileal brake (post-fat DCTT, PYY and neurotensin) were higher in patients with than without SIBO. Interpretation & conclusions: Fat infusion reduced proximal gut MI, increased DCTT, PYY, and neurotensin among patients with TS. Malabsorbed fat might cause exaggerated ileal brake reducing gut motility, promoting SIBO and bacterial colonization and malabsorption in TS.
ABSTRACT
OBJECTIVES: Although DLFD is the most common subtype of functional dyspepsia in the Orient including Korea, previous studies on gastric emptying in DLFD patients are inconclusive and reports on small bowel transit in these patients are uncommon. This study is to evaluate the occurrence of delayed gastric emptying(GET) and orocecal transit time(OCTT) in DLFD patients.' METHODS: 98 DLFD patients without organic disease including diabetes (M:F=23:75, Mean Age=43.1(23-69)) and 67 normal subjects (20 for GET and 47 for OCTT, Mean Age=39.9(25-69)) without gastrointestinal problems were recruited. Solid phase gastric emptying was assessed by radionuclide scintigraphy using ADAC dual head gamma camera after ingestion of 99mTc labeled 425 calorie solid meal. OCTT was determined by the measuring exhaled hydrogen every 10 minutes for 3 hours after ingestion of 60.5 calorie potato soap with 20gm lactulose. OCTT was defined by the time interval between test meal to sustained increase in exhaled breath hydrogen by 10ppm above baseline. A delayed GET was defined as T1/2 above the mean value plus 1 SD of controls (74.6 +/- 17.6 min, M +/- SD) and a delayed OCTT as time exceeding the mean value plus 2 SD(81.9 +/- 13.3 min, MSD). RESULTS: Among the 98 DLFD patients, only 7(7.1%) patients had a delayed GET(66.04 +/- 16.1 min vs 74.6 +/- 17.6 min, p=0.14) while a delayed OCTT was found in 36(36.7%) patients(100 +/- 32.9 min vs 81.9 +/- 13.3 min, p<0.01) and 3(3.1%) had both delayed GET and OCTT. CONCLUSION: Delayed OCTT was more frequently observed than delayed GET which was not significant comparing to wide ranged controls. Small bowel transit rather than gastric emptying plays some role in pathophysiology of the patients with DLFD.