Abnormal tryptophan levels can have various causes, just like most other symptoms. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose abnormal tryptophan levels, we could:
Tryptophan. If your blood or urine tryptophan levels have been measured within the past 3 months, what was the result?
Possible responses:→ No / over 3 months ago / don't know
→ Very low
Blood tryptophan will be decreased below normal values in cases of carcinoid tumor or syndrome when the hormone serotonin is being produced.