Endocrine Abstracts

Introduction: The prevalence of congenital malformations (CM) in congenital hypothyroidism (CH) is higher than expected, particularly for cardiac malformations, but the published data vary considerably – from 2.4% to 24% – in different series.

Methods: Using existing databases for CH and Scottish population statistics, we have retrospectively determined the prevalence of cardiac, non–cardiac and syndromic disorders in Scotland since the introduction of newborn screening.

Results: Five–hundred and six cases of true CH have been logged in Scotland since 1979 including 489 born between 1980 and 2008, giving a period prevalence of 1:3,617 live births. Twenty–five children had the following disorders: Dysmorphic syndromes (9) – pseudohypoparathyroidism (PHP)1a (1), PHP1b (1), Pendred syndrome (2), Sotos (1), Beckwith–Wiedemann (1), 14;15 translocation (1), unclassified (2 – one died); cardiac (7) – PDA (2 –1 preterm, 1 died), VSD (2), Truncus arteriosus (1 –died), Pulmonary stenosis (PS) (1), ASD, PS and anomalous pulmonary veins (1); non–cardiac: developmental dysplasia of hip (DDH) (4, 1 with cleft palate), oral cleft (2, 1 with dysmorphic features, 1 with DDH), hypoplastic right kidney (1), deafness not associated with Pendred syndrome (2), extra digits (2 siblings), myelomeningocele with hydrocephalus and talipes (1). Twelve children had multiple malformations. Excluding the 4 children with PHP & Pendred syndrome, the prevalence of congenital and cardiac malformation in the cohort of 506 children was 4.2% and 1.4% compared with 3.2% and 0.5% respectively for the Glasgow Registry 1980–97.

Conclusion: The overall prevalence of congenital malformation in Scottish children with true CH is only slightly higher than that of the general Scottish population and less than reported elsewhere. This difference may reflect smaller cohorts and the inclusion of newborns with transient hyperthyrotropinaemia in other series.