The Comparison of Iodine-Type and MnO-Type Oxidation for Measuring the Levels of Urine Neopterin and Biopterin in Patients with Hyperphenylalaninemia: A Descriptive-Analytic Study in Iran.

Fresh urine sample is required for measurement of pterins in patients with hyperphenylalaninemia (HPA) for detection of tetrahydrobiopterin (BH) coenzyme deficiency. The present study aimed to measure the levels of neopterin and biopterin in the urine of patients with HPA using manganese dioxide (MnO) and iodine oxidation methods. The levels of neopterin and biopterin in the urine of 124 patients were measured using two methods of oxidation (MnO and iodine) and the results were statistically analyzed using correlation test, Roc-Curve and ANOVA in SPSS-20 software. The level of significant was determined to be  > 0.05. Patients age mean ± SD = 4.96 year, neopterin and biopterin mean ± SD in 124 patients were 2.75 mmol/molcr and 2.49 mmol/molcr. Correlation regression between two methods (iodine and MnO oxidation) was 0.99. There was no significant difference between the two oxidation methods ( > 0.05). The results of this study showed that MnO oxidation can be a suitable alternative method instead of iodine oxidation for measurement of urine neopterin, biopterin and diagnosis of BH deficiency.