Medicine Medical SuppliesDetection Kit
5-Hydroxyindoleacetic acid (5-HIAA) is in fact the main metabolite of serotonin and is often used to determine serotonin levels in the body by analysing urine samples of 5-HIAA. Both of these are produced in excess by many carcinoid tumors, in particular those forming carcinoid syndrome of hepatomegaly, flushing, bronchospasm, heart disease and diarrhea. This has led 5-HIAA being frequently used for the diagnosis of carcinoid tumors of the enterochromaffin cells in the small intestines (this releases large quantities of serotonin). Elevated serotonin (also known as hyperserotonemia) is one of the primary biological findings in autism and there is evidence that 5-HIAA may be elevated in patients with autistic spectrum disorders. Also, there have been cases of low levels of 5-HIAA found in the cerebrospinal fluid that have been associated with aggressive behaviour and suicide by violent means, there is a direct correlation with diminished serotonin levels.
It has been well documented that a large number of substances that are present in urine have the ability to interfere with the traditional 5-hydroxy-3-indole acetic acid assayed by diazotization with nitrosonaphtol in order to form a purple colour. There have been many attempts to overcome this problem by a combination of fluorometry, ion exchange chromatography and even recently high performance liquid chromatography has been used. All of these methods are time consuming, require solvent extraction and lack sensitivity. The 5-HIAA ELISA assay is a new procedure that is simple method for the in vitro quantification offering good sensitivity and producing accurate results for this important marker of carcinoid syndrome using a small amount of urine samples.