Chapter 8: 1.3 - Tryptophan Disorder Flashcards
Tryptophan Disorder (2)
- Indicanuria
2. 5-Hydroxyindoleacetic Acid
Under normal condition:
tryptophan enters the intestines
(2)
- reabsorbed for the production of protein
- converted to indole by intestinal bacteria
- excreted in the feces
Abnormal conditions that cause over conversion of tryptophan to indole: (4)
- obstruction
- abnormal bacteria
- malabsorption syndromes
- Hartnup’s disease
- rare inherited disorder
- intestinal reabsorption and renal tubular reabsorption problem
- leads to generalized aminoaciduria (Fanconi’s Syndrome)
Hartnup’s Disease
- blue color of urine, when exposed to air
- Blue diaper syndrom
Indicanuria
Indicanuria tests: (3)
- Obermayer’s Test
- Jaffe’s test
- Jolle’s test
-another metabolite of tryptophan that is in excess with certain malignacies
5-Hydroxyindoleacetic Acid
-produced from tryptophan by argentaffin cells in the intestine for smooth muscle stimulation.
Serotonin
- due to carinoid tumors involving the argentaffin cells
- produce excess serotonin, resulting to elevation of urinary 5-HIAA
5-Hydroxyindoleacetic acid
normal daily exretion of 5-HIAA
2-8 mg
5-HIAA: argentaffin cell tumors produce (pathologic)
160-628/24 hours
5-HydroxyIndoleacetic Acid Tests:
2
- Ferric Chloride
2. Sjoerdsma Test
5-HydroxyIndoleacetic Acid Tests:
recommended specimen
first morning urine - prevent false-negative results
5-HydroxyIndoleacetic Acid Tests:
bananas, pineappples, tomatoes
medications: phenothiazines acetanilids.
Diet: food not allowed
- rich in serotonin
5-HydroxyIndoleacetic Acid Tests:
Ferric chloride
color
blue-green
