Organic Acids Test (OAT) - Nutritional and Metabolic Profile

4-Hydroxyphenylacetic (Males Age 13 and Over)

Optimal result: 0 – 18 mmol/mol creatinine

Mosaic Diagnostics

By Healthmatters Editorial Team

Peer-reviewed sources

High 4-Hydroxyphenylacetic acid may be associated with small intestinal bacteria overgrowth (SIBO) due to its production by:

- C. difficile

- C. stricklandii

- C. lituseburense

- C. subterminale

- C. putrefaciens

- C. propionicum

C. difficile can be distinguished from the other species by its production of 4-cresol. No other Clostridia species produce 4-cresol.

Elevated values of 4-hydroxyphenylacetic acid are common in:

- Celiac disease

- Cystic fibrosis

- Jejuna web

- Transient lactose intolerance

- Giardia infection

- Ileal resection

- Ileo-colic intersusseception

- Septicemia

- Projectile vomiting.

It is likely that the phenol 4-hydroxyphenylacetic is an inhibitor of dopamine-beta-hydroxylase and that people with high values may have elevated dopamine and HVA/VMA ratios.

Possible treatment:

Treatment with probiotics or antibiotics may be clinically useful.

If levels are extremely high:

Extremely elevated levels of at least 100 mmol/mol creatinine are associated with tyrosinemia, which can be due to immature development of enzymes in infants or to genetic deficiencies.

A tyrosine metabolic product of GI bacteria.

4-Hydroxyphenylacetate is a tyrosine metabolic product of certain Clostridia bacteria. Elevated levels are associated with Clostridia overgrowth, small intestinal bowel overgrowth (SIBO), or small bowel disease. May also indicate celiac disease.

For individuals with normal, healthy intestinal function, the compound p-Hydroxyphenylacetate should not appear as more than background concentrations in urine.

Measurement of 4-hydroxyphenylacetic acid excretion in urine is useful in screening for diseases of the small intestine associated with bacterial overgrowth.

References:

- http://www.hmdb.ca/metabolites/HMDB0000020

- https://www.ncbi.nlm.nih.gov/pubmed/476929

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4-Hydroxyphenylacetic (Males Age 13 and Over)

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Clinical Sources & References

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