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Intestinal amino acid content in critically ill patients
B Ahlman1, O Ljungqvist, B Persson
1Department of Surgery, Karolinska Hospital, Stockholm, Sweden.
JPEN. Journal of Parenteral and Enteral Nutrition
|July 1, 1995
Summary
Critical illness alters intestinal mucosa amino acid profiles, with elevated glutamine in the duodenum and phenylalanine in both duodenum and colon. These changes differ from starvation or surgical trauma effects.
Area of Science:
- Gastroenterology
- Biochemistry
- Critical Care Medicine
Background:
- Intestinal mucosa plays a vital role in nutrient absorption and immune function.
- Critical illness can significantly impact gastrointestinal physiology and function.
- Understanding mucosal biochemistry is crucial for managing critically ill patients.
Purpose of the Study:
- To quantify free amino acid and total protein concentrations in human intestinal mucosa during critical illness.
- To identify specific amino acid alterations in the duodenal and colonic mucosa of critically ill patients.
Main Methods:
- Endoscopic biopsy specimens were collected from the duodenum and distal colon of 19 critically ill patients.
- Free amino acids were analyzed using ion exchange chromatography with fluorescence detection.
- Total protein content was determined via the Lowry method.
Main Results:
- Intestinal mucosa exhibited typical amino acid patterns, notably high taurine, aspartate, and glutamic acid.
- Duodenal mucosa showed elevated glutamine, while rectal levels were depressed; descending colon levels were unchanged.
- Phenylalanine, valine, and leucine were elevated in the duodenum; methionine and phenylalanine were elevated in the colon.
Conclusions:
- Mucosal amino acid and protein alterations in critical illness are distinct from those observed in starvation or moderate surgical trauma.
- These findings highlight unique metabolic adaptations within the intestinal mucosa during critical illness.
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