Long-term outcome of thyrotoxicosis in childhood and adolescence in the west of Scotland: the case for long-term antithyroid treatment and the importance of initial counselling.

BACKGROUND: Thyrotoxicosis is both rarer and more severe in children than in adults, rendering management difficult and often unsatisfactory. OBJECTIVE: To ascertain outcome in a geographically defined area of Scotland between 1989 and 2014. METHOD: Retrospective case note review with follow-up questionnaire to family doctors for patients with Graves' disease and Hashimoto's thyroiditis. RESULTS: Sixty-six patients (58 females:8 males) comprising 53 with Graves' disease and 13 with Hashimoto's thyroiditis were diagnosed at median 10.4 (2.9-15.8) years and followed up for 11.8 (2.6-30.2) years. Antithyroid drug (ATD) therapy was stopped electively in 35 patients after 4.5 (1.5-8.6) years, resulting in remission in 10/13 Hashimoto's thyroiditis and 10/22 Graves' disease. Side effects occurred in 12 patients receiving carbimazole, six of whom changed to propylthiouracil; no adverse events occurred in the latter patients.Second-line therapy was given to 37 patients (34 with Graves' disease), comprising radioiodine (22) at 15.6 (9.3-24.4) years for relapse (6), poor control/adherence (14) or electively (2); and surgery (16) at 12 (6.4-21.3) years for relapse (4), poor control/adherence (5) and electively (7). Adherence problems with thyroxine replacement were reported in 10/33 patients in adulthood. CONCLUSIONS: Hashimoto's thyroiditis should be distinguished from Graves' disease at diagnosis since the prognosis for remission is better. Remission rates for Graves' disease are low (10/53 patients), time to remission variable and adherence with both ATD and thyroxine replacement often problematic. We recommend (a) the giving of long-term ATD rather than a fixed course of treatment in GD and (b) meticulous and realistic counselling of families from the time of diagnosis onwards.

Early identification of pituitary dysfunction in congenital nasal pyriform aperture stenosis: recommendations based on experience in a single centre.

BACKGROUND: Congenital nasal pyriform aperture stenosis (CNPAS) is an increasingly recognised cause of upper airway obstruction associated with midline abnormalities. Studies have described pituitary dysfunction in 40% of patients. We aimed to develop guidelines for: (a) the early identification of pituitary insufficiency to minimise surgical risk and (b) to stratify patients for follow-up. METHODS: Retrospective case note review of patients with CNPAS between 2000 and 2014 in a tertiary paediatric unit. RESULTS: 20 patients (12 female:8 male) were analysed; 16 were diagnosed during the neonatal period while 4 were diagnosed later. There was no consistent approach in the evaluation of the pituitary axis at diagnosis. Pituitary dysfunction was identified in 3 (15%) patients, 2 of whom were found during evaluation of short stature in mid-late childhood. Hypoglycaemia and conjugated hyperbilirubinaemia, but not the degree of stenosis, were highly predictive of pituitary dysfunction (p < 0.05). Available height standard deviation score (SDS) data at 1 year of 70% of our patients identified both of the late-diagnosed growth hormone-deficient patients, with SDS of -2.6 and -3.6, respectively. CONCLUSION: All CNPAS patients should have MRI of the brain and baseline endocrine investigations at diagnosis. Growth monitoring for at least 1 year is recommended as low, or falling, height SDS at 1 year is a good predictor of pituitary dysfunction.

Effect of oxandrolone and timing of oral ethinylestradiol initiation on pubertal progression, height velocity and bone maturation in the UK Turner study.

BACKGROUND: A UK study showed final height in Turner syndrome (TS) girls receiving growth hormone is affected by age at pubertal induction and oxandrolone (Ox). Using data from that study, we analysed the effect of timing of oral ethinylestradiol (EE2) and Ox on height velocity (HV), bone maturation and pubertal progression, and compared growth response in EE2-treated versus spontaneous puberty. METHODS: Analysis of HV, bone age and pubertal stage in 92 TS girls (7-13 years) randomised to Ox (0.05 mg/kg/day; max: 2.5 mg/day) or placebo from 9 years, and EE2 (year 1: 2 µg/day; year 2: 4 µg/day; year 3: 6/8/10 µg/day×4 months) or placebo at 12 years with EE2 at 14 years. Girls enrolled at >12.25 years received EE2 at 14 years ('late group'). RESULTS: Fifty-six girls were randomised to EE2 at 12 years (n=28, 11 Ox) or 14 years (n=28, 13 Ox); there were 19 girls in the late group (9 Ox) and 17 girls with spontaneous puberty (10 Ox). Girls receiving EE2 at 12 versus 14 years had faster bone maturation, but neither group showed acceleration. Ox increased HV without altering bone maturation or pubertal progression. Girls with spontaneous puberty had greater pubertal growth (mean PHV 8.5 cm/year; p<0.001) and height gain (p<0.001) than EE2-treated girls despite similar mean enrolment height SD and dysmorphology scores. CONCLUSION: Pubertal induction with EE2 does not replicate the acceleration observed in unaffected girls or TS girls with spontaneous puberty.

Functional characterisation of the H365Y mutation of the 21-hydroxylase gene in congenital adrenal hyperplasia.

The study subject was a 13 day-old boy admitted to hospital, with weight loss since birth. He presented with the vomiting and hypotension that are classical features of congenital adrenal hyperplasia (CAH). The most common type of CAH is an autosomal recessive disorder caused by mutations in the 21-hydroxylase (CYP21A2) gene. To examine the CYP21A2 gene, gene-specific PCR was carried out, followed by sequencing. The baby was shown to be a compound heterozygote H365Y/R356W for two CYP21A2 gene mutations each inherited from a different parent. One of the mutations has not previously been functionally characterised. The mutations were reconstructed in an expression plasmid and characterised in vitro after transient transfection into human embryonic kidney (HEK293T) and hepatoblastoma (C3A) cell lines followed by measurement of enzyme activity. The CYP21A2 H365Y mutant exhibited minimal 21-hydroxylase activity to convert 17-hydroxyprogesterone to 11-deoxycortisol or progesterone to 11-deoxycorticosterone. Western immunoblotting indicated that the H365Y enzyme was produced in more variable amounts than wild type; in particular, the H365Y mutant protein may be unstable and/or subject to a more rapid degradation by the human proteosome as well as catalytically inefficient. The double mutant genotype with a severe mutation on each allele is compatible with the clinical presentation.

Heterogeneous tissue in the thyroid fossa on ultrasound in infants with proven thyroid ectopia on isotope scan--a diagnostic trap.

BACKGROUND: Thyroid imaging is of proven help in establishing a diagnosis of congenital hypothyroidism in infants. US often shows tissue in the thyroid fossa when radionuclide scintigraphy reveals only ectopic uptake. OBJECTIVE: Our hypothesis was that the use of US alone could lead to the mistaken diagnosis of normal or dysplastic thyroid in cases of scintigraphy-proven thyroid ectopia. MATERIALS AND METHODS: We undertook a detailed retrospective review and analysis of imaging and concurrent biochemistry in infants with thyroid ectopia, confirmed by radionuclide scintigraphy. RESULTS: Eighteen infants had thyroid ectopia; ten of the original US reports had suggested that cervical thyroid tissue was present. Review showed bilateral tissue in the thyroid fossa in all that was non-thyroidal in nature since, apart from showing no radionuclide uptake, it exhibited some or all of the following typical features: hyperechogenicity, heterogeneity, small size, poor vascularity, and anechoic and/or hypoechoic cysts. Also, extension of the tissue both around and behind the large cervical blood vessels was a universal finding. CONCLUSION: Considerable experience is required to interpret neonatal thyroid US. We caution against diagnosing a dysplastic/hypoplastic thyroid gland in situ on the basis of US alone, particularly if the tissue exhibits any of the non-thyroidal features described.

Hypoechoic thyroid nodules on ultrasound 4 years after prenatal exposure to radioiodine: resolution with thyroxine therapy.

UNLABELLED: We describe an infant inadvertently exposed to radioiodine at 17 weeks gestation. His mother had received 400 MBq of (131)I for hyperthyroidism (total T4 178 nmol/L, thyroid stimulating hormone (TSH) <0.1 mU/L, 4-h (131)I uptake 16%). Following cordocentesis at 27 weeks (free T4 12.7 pmol/L, TSH 35.4 mU/L) intra-amniotic thyroxine was withheld and a male infant was born at 39 weeks gestation, birthweight 3520 g. Cord TSH was low (0.1 mU/L), total T4 151 nmol/L on day 4, the mother having received no medication during pregnancy. Postnatal follow-up showed mild TSH elevation (11.0-19.4 mU/L) but normal free T4 (9-12.7 pmol/L) during the first 2 years of life following which the child was discharged still untreated. On recall at 4.3 years, TSH elevation persisted (15.4 mU/L) and ultrasound showed several hypoechoic thyroid nodules within the left lobe that disappeared after thyroxine treatment. CONCLUSION: In the event of inadvertent exposure to radioiodine in utero, the infant should receive thyroxine therapy from birth in order to protect the thyroid gland from TSH over-stimulation, however mild.

Maternal age in patients with septo-optic dysplasia.

AIM: To determine whether patients with septooptic dysplasia (SOD) are of normal birth weight and gestation but are born to mothers who are significantly younger than average. METHODS: Retrospective study of 30 patients with SOD attending the Royal Hospital for Sick Children, Glasgow. Birth data for the Scottish population were used for comparison. RESULTS: Mean birth weight was 3.42 (range 2.66-4.18) kg. One patient was born preterm while the rest were born at term. Data for the Scottish population were available from 1979 onwards and 26 patients born after this year were selected for analysis. Median maternal age in this group was 21 (range 16-41) years, significantly lower than the median maternal age for Scotland of 27.12 (range 25.8-28.6) years (95% CI 4.8-8.0 years). CONCLUSION: Patients with SOD are of normal birth weight and gestation but are born to mothers who are significantly younger than average.