Elevated 5-hiaa

[Mother of Jibril]

Today I found out I have another autoimmune disorder... my immune system has been making antibodies to the IgE receptors on my mast cells, tricking them into releasing their contents. The symptoms are the same as any severe allergic reaction (hives, dizziness, vomiting, etc...), but the reaction is not caused by an external substance. Interesting. I'm actually happy to know... too bad there's no cure. At least people sometimes go into remission

Anyway... I have a question. I'd be so grateful if anyone has any ideas about this! Today I also got the results of a 24-hour urine test for 5-HIAA (which is a metabolite of serotonin). A normal level at the lab that did my test is under 6.0. A "high" result (above 25) is diagnostic for carcinoid tumors, a slow-growing tumor in your digestive system that gives off serotonin (NOT a good thing to have). My level was 8.4. So... probably not carcinoid... but my allergist wants me to repeat the test. I've been reading that one cause for a "false positive" (elevated, but not carcinoid) is celiac disease and other malabsorption syndromes like Whipple's disease, tropical sprue, etc...

Does anyone know anything about this? I've read that people with untreated celiac can have 5-HIAA levels between 11 and 25... I've been off gluten nine months.

[gfb1]

Today I found out I have another autoimmune disorder... my immune system has been making antibodies to the IgE receptors on my mast cells, tricking them into releasing their contents. The symptoms are the same as any severe allergic reaction (hives, dizziness, vomiting, etc...), but the reaction is not caused by an external substance. Interesting. I'm actually happy to know... too bad there's no cure. At least people sometimes go into remission

Anyway... I have a question. I'd be so grateful if anyone has any ideas about this! Today I also got the results of a 24-hour urine test for 5-HIAA (which is a metabolite of serotonin). A normal level at the lab that did my test is under 6.0. A "high" result (above 25) is diagnostic for carcinoid tumors, a slow-growing tumor in your digestive system that gives off serotonin (NOT a good thing to have). My level was 8.4. So... probably not carcinoid... but my allergist wants me to repeat the test. I've been reading that one cause for a "false positive" (elevated, but not carcinoid) is celiac disease and other malabsorption syndromes like Whipple's disease, tropical sprue, etc...

Does anyone know anything about this? I've read that people with untreated celiac can have 5-HIAA levels between 11 and 25... I've been off gluten nine months.

once upon a time, i used to analyze catcholamines, indoleamines (serotonin is one) and their metablolites for a living. measuring 5-hiaa is nontrivial, and depending on the method there are lots of things that cross-react with the antibodies (or, co-elute in a chromatogram). there are also a variety of foods and meds that can increase levels of serotonin&metabolites in both blood and urine. haul your food diary into the docs office to make sure, some foods can influence these levels for a day or two.

repeating the test is good advice.

[Mother of Jibril]

once upon a time, i used to analyze catcholamines, indoleamines (serotonin is one) and their metablolites for a living. measuring 5-hiaa is nontrivial, and depending on the method there are lots of things that cross-react with the antibodies (or, co-elute in a chromatogram). there are also a variety of foods and meds that can increase levels of serotonin&metabolites in both blood and urine. haul your food diary into the docs office to make sure, some foods can influence these levels for a day or two.

repeating the test is good advice.

Thanks for your insights! I did have a whole list of foods and medications to avoid for three days before the test (and during the test, obviously)... chocolate, bananas, pineapple, eggplant, walnuts, plums, tomatoes, avocado, plus ethanol (I don't drink, so no big deal), acetominophen, and cough syrups like Robitussin. I'm not too worried about the test and I don't mind repeating it. I'm just wondering if it gives me any clues to other things that might be going on in my body.

I know some tests are only useful if there's an obvious negative or obvious positive... maybe this is one of them? It sounds pretty complicated to analyze.

[gfb1]

Thanks for your insights! I did have a whole list of foods and medications to avoid for three days before the test (and during the test, obviously)... chocolate, bananas, pineapple, eggplant, walnuts, plums, tomatoes, avocado, plus ethanol (I don't drink, so no big deal), acetominophen, and cough syrups like Robitussin. I'm not too worried about the test and I don't mind repeating it. I'm just wondering if it gives me any clues to other things that might be going on in my body.

I know some tests are only useful if there's an obvious negative or obvious positive... maybe this is one of them? It sounds pretty complicated to analyze.

its hard to say what it all means; 5hiaa really isn't a primary diagnostic for many conditions and (as you pointed out in your first post), the values are usually 'off the charts' if there is an intestinal tumor present. repeating the test will help to determine if its a spurious result (or if 5hiaa levels are spiking irregularly).

btw -- sorry to hear that you've got some new symptoms (probably should have mentioned that in my first reply.... insert oblivious-scientist joke here).. seems like celiacs just keep battling along. hang in there.