Interference of hydroxyphenylpyruvic acid, hydroxyphenyllactic acid and tyrosine on routine serum and urine clinical chemistry assays; implications for biochemical monitoring of patients with alkaptonuria treated with nitisinone.
Clin Biochem
; 71: 24-30, 2019 Sep.
Article
in En
| MEDLINE
| ID: mdl-31228435
ABSTRACT
OBJECTIVES:
We have assessed the effect of elevated concentrations of hydroxyphenylpyruvic acid (HPPA), hydroxyphenyllactic acid (HPLA) and tyrosine, on a range of chemistry tests in serum and urine to explore the potential for chemical interference on routine laboratory analyses in patients with alkaptonuria (AKU) treated with nitisinone and similarly implications for patients with hereditary tyrosinemia type 1 (HT-1). MATERIALS ANDMETHODS:
HPPA, HPLA and tyrosine were added separately to pooled serum from subjects without AKU in a range of assays with Roche Modular chemistries. Effects on urine were assessed by changes in urine strip chemistries after mixing a positive control urine with various amounts of the test compounds and reading on a Siemens urine strip meter.RESULTS:
No significant effect (pâ¯>â¯0.1) was observed up to 225⯵mol/L of HPPA and HPLA, and up to 5000⯵mol/L tyrosine, on any of the serum-based assays including those with peroxidase-coupled reaction systems of enzymatic creatinine, urate, total cholesterol, HDL cholesterol and triglyceride. Both the monohydroxy HPPA, and the dihydroxy homogentisic acid (HGA), at increased urine concentrations typical of nitisinone-treated AKU and non-treated AKU respectively, did however show marked negative interference in strip assays for glucose and leucocytes; i.e. those with peroxide-linked endpoints. The effect of increased HPLA was less marked.CONCLUSIONS:
In patients with AKU or on nitisinone treatment and HT-1 patients on nitisinone, urine strip chemistry testing should be used sparingly, if at all, to avoid false negative reporting. It is recommended that urine assays should be organised with a suitable specialist laboratory.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Phenylpropionates
/
Phenylpyruvic Acids
/
Tyrosine
/
Cyclohexanones
/
Alkaptonuria
/
Enzyme Inhibitors
/
4-Hydroxyphenylpyruvate Dioxygenase
/
Nitrobenzoates
Limits:
Humans
Language:
En
Journal:
Clin Biochem
Year:
2019
Document type:
Article
Affiliation country:
United kingdom
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA