Intestinal Absorption and Unmediated Permeation of Sugars in Post-Infective Tropical Malabsorption (Tropical Sprue)

Abstract

Differential absorption of D-xylose and 3-O-methyl-D-glucose, and unmediated intestinal permeation of lactulose and L-rhamnose has been investigated in 14 patients with diarrhoea following tropical exposure and in 16 healthy control subjects. Five had malabsorption of fat, D-xylose and B₁₂ (‘tropical malabsorption’ (TM) group), and that was absent or minimal in the others (‘tropical diarrhoea’ (TD) group). After combined ingestion of the four test sugars in iso-osmolar solution a marked depression in plasma D-xylose concentration (with a slow rise) occurred in all of the TM group; the TD group did not differ significantly from the controls. In contrast, 3-O-methyl-.D-glucose absorption was similar in all three groups. Urine analysis demonstrated that intestinal permeation of lactulose was increased and that of rhamnose decreased in the TM group compared with the controls. Ingestion as a hyperosmotic solution further enhanced abnormal lactulose permeation in the TM group. Although some of the TD group showed one or the other of these changes, discrimination of the TM group from the TD and control groups was improved when results were expressed as lactulose/rhamnose differential permeation ratios, especially when using a hyperosmotic stress. Similar abnormalities have previously been demonstrated in untreated gluten-induced enteropathy (coeliac disease). The magnitude of the absorption defects demonstrated in TM are more severe than would be anticipated from the jejunal mucosal abnormalities alone; this suggests that there is probably significant pathology in the distal small intestine (including the ileum) in TM.

Gastrointestinal permeability following cardiopulmonary bypass: a randomised study comparing the effects of dopamine and dopexamine

“…Four saccharides: 3-O-M-D-glucose, D-xylose, L-rhamnose and lactulose were employed to assess active carrier-mediated, passive carrier-mediated, transcellular and paracellular transport in the small intestine, respectively, as described in full elsewhere [17,18]. Briefly, 100 ml of water containing 0.2 g 3-O-M-D-glucose, 0.5 g D-xylose, 1.0 g L-rhamnose and 5.0 g of lactulose was instilled into the stomach via the integral nasogastric tube in the tonometer.…”

Abnormal Small Intestinal Permeability in Patients with Idiopathic Malabsorption in Tropics (Tropical Sprue) Does Not Change Even After Successful Treatment

“…TS tropical sprue, HS healthy subjects, TSP trimethyl silyl propionic acid Dig Dis Sci (2011) 56:161-169 165 associated with incomplete resolution of the disease, as evidenced by higher stool frequency and less weight gain. Abnormal SIP has been reported in two studies on a small number of patients with TS [11,12]. A study from our group on estimation of SIP using urinary excretion of lactulose and mannitol by 1 H-NMR spectroscopy in a small number of patients with malabsorption syndrome (n = 18, including 8 patients with TS) and healthy controls (n = 28) showed that the urinary excretion ratio of lactulose to mannitol was higher in patients with malabsorption syndrome as compared with in healthy controls [11].…”

“…Also, urinary excretion of lactulose was higher in patients with TS but excretion of mannitol was the same as compared with healthy controls [11]. Another study by Cook et al on SIP using urinary excretion of lactulose and L-rhamnose in 14 patients with diarrhea following tropical exposure (TS) and 16 healthy controls has shown that urinary excretion of lactulose was higher in TS patients as compared with healthy controls [12]. They showed that the magnitude of the absorption defects demonstrated in patients with TS is more severe than would be anticipated from the jejunal mucosal abnormalities [12].…”

“…There could be overlap between PI-IBS and postinfective malabsorption syndrome including TS [4]. Though abnormal SIP has been reported in two studies on a small number of patients with TS [11,12], it is not known whether such abnormality is reversible after treatment of the disease. Hence, it is worthwhile to study SIP in patients with TS, effect of treatment of the disease on its abnormality, and its relationship with clinical outcome.…”

Role of Intestinal Permeability in Monitoring Mucosal Barrier Function

“…Nonmediated permeation and mediated transport of carbohydrates are simultaneously measured by combining lactulose and L -rhamnose with D -xylose and 3-O-methyl- D -glucose [77], providing more reliable information than a single-marker test in coeliac disease [78]. Hypolactasia and intestinal permeability are simultaneously reflected by a combination of raffinose, L -arabinose and lactose [37].…”