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Visceral hypersensitivity and intolerance symptoms in lactose malabsorption
M Di Stefano1, E Miceli, S Mazzocchi
1Department of Medicine, IRCCS S.Matteo Hospital, University of Pavia, Pavia, Italy.
Neurogastroenterology and Motility
|November 2, 2007
Summary
Visceral hypersensitivity, or heightened gut sensitivity, contributes to lactose intolerance symptoms. Even without lactose malabsorption, altered gut sensitivity can trigger discomfort in some individuals.
Area of Science:
- Gastroenterology
- Digestive Health
- Functional Gastrointestinal Disorders
Background:
- Lactose malabsorption does not always cause intolerance symptoms.
- The exact causes of lactose intolerance symptom onset remain unclear.
- Visceral sensitivity alterations may contribute to functional gastrointestinal symptoms.
Purpose of the Study:
- To investigate if altered visceral sensitivity is present in individuals with lactose intolerance.
- To determine the role of fermentation in modifying intestinal sensitivity.
Main Methods:
- Evaluated 30 subjects for lactose absorption using hydrogen breath tests.
- Assessed recto-sigmoid sensitivity thresholds before and after lactulose administration.
- Utilized (13)C-octanoic and lactulose breath tests to exclude gastrointestinal transit differences.
Main Results:
- Lactulose reduced discomfort thresholds significantly in lactose-intolerant subjects.
- No significant changes in discomfort thresholds were observed in lactose malabsorbers without symptoms or normal absorbers.
- Symptom severity in intolerant individuals correlated with reduced discomfort thresholds.
Conclusions:
- Visceral hypersensitivity is a key factor in inducing lactose intolerance symptoms.
- Altered visceral sensitivity should be considered in patients with lactose malabsorption and intolerance symptoms.
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