Related Experiment Video
Updated: Aug 13, 2026

Using Multi-fluorinated Bile Acids and In Vivo Magnetic Resonance Imaging to Measure Bile Acid Transport
Published on: November 27, 2016
Increased HVA detected on organic acid analysis in a patient with Costello syndrome
A Bowron1, J G Scott, C Brewer
1Department of Clinical Biochemistry, Bristol Royal Infirmary, Bristol, BS2 8HW, UK. ann.bowron@ubht.swest.nhs.uk
Abstract:
Urine organic acid analysis is routinely performed to investigate inborn errors of metabolism; however, interpretation can be difficult owing to the detection of compounds derived from other disease states or from nonpathological causes. We describe the finding of elevated homovanillc acid (HVA) on urine organic acid analysis which was not associated with medication or a neuroendocrine tumour but with Costello syndrome.
Related Concept Videos
Serum Laboratory Studies, Stool Test, Breath Test
NMR and Mass Spectroscopy of Carboxylic Acids
While α protons of carboxylic acids absorb at 2–2.5 ppm, β protons absorb further upfield.
Carboxylic acids are easily identified by dissolving them in deuterium oxide, which results in a rapid exchange of the acidic protons with deuterium. This leads to the disappearance of the acidic...

