Unclear DAO laboratory value
January 27, 2018 | 20,00 EUR | answered by Dr. med. Frauke Gehring
Hello,
I have a question regarding a laboratory finding in the context of a possible HIT:
"Parameter: Histamine in Li-Heparin Plasma Result: 0.8 ug/l Reference: less than 1 ug/l"
This is understandable so far.
"Parameter: Diamine oxidase (DAO) Result: -10.0 U/ml Reference: greater than 10 U/ml"
Is a negative value (-10!) possible here?
Thank you!
Good day,
No, a negative value is not possible here, so I would recommend inquiring again. DAO is a histamine degrading enzyme. If there is not enough of it present, it can lead to histamine intolerance.
If there was no enzyme present at all, the value would be zero, which would be extremely unusual because we usually measure a certain DAO activity of around 2 UL/ml. Enzyme activity cannot be less than zero! Perhaps there is a typographical error here.
Sincerely, Dr. Gehring
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