Comparison of IQ scores between children with phenylketonuria and healthy children referring to Besat Hospital in Sanandaj between 2017 and 2018

Phenylketonuria is a genetic and congenital metabolic disorder with autosomal recessive transmission. In this disease phenylalanine is not converted to tyrosine due to lack of  phenylalanine hydroxylase enzyme which results in increased phenylalanine level in the blood and brain. The aim of this study was to compare IQ scores between the children with phenylketonuria and healthy children referring to Besat Hospital in Sanandaj in 2017-2018.

This case-control study included all the patients referring to PKU and pediatric clinics who had been under treatment since birth as our case group , and healthy children referring to other pediatric clinics of the hospital as control group. Goodinow’s intelligence test was used to measure cognitive, mental abilities and children's intelligence. Data were analyzed by chi square and independent t-test.

The results showed that 46 (69.7%) patients were male and 20 (30.3%) were female. The mean age of the subjects was 6.34±2.52 years. There was no significant difference in the IQ mean scores between the two groups (p=0/06).

The most important clinical signs of this disease are mental retardation, microcephaly, behavioral disorders, seizure, limb stiffness, restlessness, unrest, hyperactivity, eczema and light colored skin and hair. Diagnosis of the disease before the third week of life, and proper nutritional therapy with necessary care before the age of one month can decrease the symptoms of the disease.