Incidence of phenylketonuria and the effect of prevention national program on reducing its incidence in the population covered by Kerman University of Medical Sciences during 2007-2020

Phenylketonuria (PKU) is the most common inherited metabolic disease in Iran that can be prevented by prenatal diagnostic tests (PND). This study was performed aimed to determine the incidence of PKU and the effect of implementing a prevention program on reducing its incidence in the population covered by Kerman University of Medical Sciences.

This was a descriptive study on health system research. All PKU carrier couples and patients covered by Kerman University of Medical Sciences in 2019 were studied. Data were obtained from the national form of epidemiological study of genetic diseases and genetic surveillance form from the Deputy Minister of Health. Frequency tables and graphs were used to describe the information.

In this study, 68 patients and 63 carrier couples were covered and 37 (60.6%) carrier couples were at risk of having a sick child and all of them were under the care of health care centers. For 91.9% of them and 61.9% high-risk relatives, the type of gene mutation was determined. PND tests were performed on 28 (87.5%) pregnant women. Seven affected fetuses were diagnosed, all of which were aborted with parental consent. 32 high-risk couples (86.5%) used safe method of contraception. The 13-year incidence of PKU in the whole region was 1.13 and the expected incidence was 1.36 per 10,000 live births.

Implementation of prevention program had an effect on reducing the incidence of PKU. The high frequency of consanguineous marriages can affect the high incidence of PKU. It is necessary to identify the patient's relatives who are at risk of having a sick child (consanguineous marriage), refer them to a genetic counseling center and determining their status can be effective in reducing the incidence of the disease.