Does fluid loading influence measurements of intestinal permeability?

Area of Science:

• Gastroenterology
• Clinical Nutrition
• Pharmacokinetics

Background:

• Urinary recovery of enterally administered probes is a clinical test for intestinal mucosal permeability.
• Evidence suggests that diuresis and renal function influence the recovery of certain sugar probes.
• This study investigates the impact of fluid loading on sugar probe recovery.

Purpose of the Study:

• To assess the effect of fluid loading on the urinary recovery of multiple sugar probes in healthy volunteers.
• To determine if fluid intake alters intestinal permeability measurements using sugar probes.
• To evaluate the influence of hydration status on the reliability of these probes.

Main Methods:

• A cross-over study involving 10 healthy volunteers.
• Administration of 3-O-methyl-D-glucose, D-xylose, L-rhamnose, and lactulose.
• Randomized fluid loading with 2 liters of Ringer acetate or no fluid over 3 hours.
• Measurement of sugar concentrations in 5-hour urine samples.

Main Results:

• Fluid loading significantly increased urine production and the urinary recovery of D-xylose.
• Urinary recovery of 3-O-methyl-D-glucose, L-rhamnose, and lactulose remained unaffected by fluid loading.
• Neither the lactulose/rhamnose nor the 3-OMG/rhamnose ratio showed changes with fluid loading.

Conclusions:

• Fluid loading enhances carbohydrate transport, as indicated by increased D-xylose recovery.
• Hydration status does not alter the lactulose/rhamnose ratio, suggesting its stability as a permeability marker.
• Further research is needed to understand fluid effects on sugar probes in patients with organ dysfunction.