Article Type

Original Study


Objective The aim of the study was to compare the incidence of congenital hypothyroidism (CH) in Jordan with its incidence worldwide. Background CH is a preventable disease of mental retardation. Its incidence worldwide is almost 1 : 4000. Early screening, diagnosis, and treatment are mandatory to prevent later sequelae. Materials and methods This is a descriptive retrospective analysis of 13 452 newborns screened for CH. Data were collected from records during the period from February 2010 to November 2013 in the pediatric endocrine clinic in Queen Rania Al Abdullah Hospital for Children at King Hussein Medical Center, Amman, Jordan. There were 5978 male and 7474 female participants. Their age ranged between 3 and 10 days. Heel-prick whole blood was collected on a filter paper and sent everyday to the Princess Eman Laboratory Center for analysis. The thyroid-stimulating hormone (TSH) level using the enzyme-linked immunosorbent assay was considered as normal if the TSH value was less than 10 mU/ml, equivocal at values between 10 and 20 mU/ml, and positive for CH if TSH values were greater than 20 mU/ml. Parents of newborns with positive and equivocal results were called to return for further assessment. Central blood samples for free T4 and TSH were sent for patients with equivocal results and for those with TSH screen greater than 20 mU/ml. These two groups were reassessed for symptoms and signs of CH. Newborns screened for CH younger than the age of 3 days and older than the age of 10 days were excluded from the study. Newborns with clinical sepsis and premature babies were also excluded. Descriptive analysis using frequencies was applied to describe the study variables. Results Out of the 13 452 newborns tested, 5978 (44%) were male and 7474 (56%) were female. Newborns were categorized into three groups according to the TSH screening result. Group 1 included 13 231 newborns [5903 male (45%) and 7328 female (55%)] with normal TSH screen less than 10 mU/ml. Group 2 included 173 newborns [52 male (30%) and 121 female (70%)] with TSH 10-20 mU/ml. Group 3 included 48 newborns [23 male (48%) and 25 female (52%)] with TSH level greater than 20 mU/ml. Central samples for T4 and TSH were sent for group 2 and group 3. In group 2, one female newborn was confirmed to have primary hypothyroidism, whereas in group 3, five newborns were diagnosed to have CH, one male and four female. Conclusion The incidence of CH in Jordan is higher than the incidence worldwide; this could be due to the higher rate of consanguineous marriages in Jordan, which can increase the incidence of primary hypothyroidism due to dyshormonogenesis, although other contributing factors should be considered.