Nongenetic causes of hypertyrosinemia that must be considered when interpreting a finding of elevated urinary tyrosine

Causas no genéticas de hipertirosinemia que deben considerarse al interpretar un hallazgo de tirosina elevada en orina

Abstract

Mr. Editor.

In several countries, newborns are screened for tyrosinemia type 1 using tyrosine as a primary marker. In some situations, elevated blood tyrosine levels are discovered due to elevated tyrosine on a urine metabolic screen. In Peru, some pediatric patients suspected of having a genetic condition (inborn error of metabolism) undergo a metabolic screening in urine that includes - among other things - the qualitative detection of tyrosine. However, when there are high levels of tyrosine in the urine this does not always mean that the patient has a genetic condition. Hypertyrosinemia is most often non-genetic in origin. Therefore, it is important to review the non-genetic causes of hypertyrosinemia and thus avoid potential misinterpretations of this finding.