The Comparison of Iodine-Type and MnO2-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 4 ) 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 2 ) and iodine oxidation methods. The levels of neopterin and biopterin in the urine of 124 patients were measured using two methods of oxidation (MnO 2 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 P  > 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 2 oxidation) was 0.99. There was no significant difference between the two oxidation methods ( P  > 0.05). The results of this study showed that MnO 2 oxidation can be a suitable alternative method instead of iodine oxidation for measurement of urine neopterin, biopterin and diagnosis of BH 4 deficiency.