Reduced circulating 4-Hydroxyphenylpyruvate dioxygenase activity

What it means

Activity or concentration of 4-hydroxyphenylpyruvate dioxygenase in the blood circulation below the lower limit of normal.

Note: 4-hydroxyphenylpyruvate dioxygenase corresponds to EC 1.13.11.27. 4-Hydroxyphenylpyruvate dioxygenase participates in the tyrosine catabolic pathway by catalyzing the conversion of 4-hydroxyphenylpyruvate to homogentisate. A deficiency in this enzyme can result in 4-Hydroxyphenylacetic aciduria.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Reduced 4-Hydroxyphenylpyruvate dioxygenase level · Reducted HPPD activity