Early assessment of hypothalamic-pituitary-gonadal function in patients with congenital hypothyroidism of central origin.

CONTEXT: Early recognition of gonadotropic dysfunction could enable well-timed growth and maturation and prevent damage to gonads and external genitalia. The adaptation of the Dutch neonatal screening program for congenital hypothyroidism in the mid 1990s resulted in enhanced detection of congenital hypothyroidism of central origin (CH-C), with high likelihood of multiple pituitary hormone deficiency, including gonadotropin (Gn) deficiency. OBJECTIVE: We analyzed GnRH test results and baseline Gn and sex hormone measurements in 15 infants with CH-C to examine these diagnostic tools for assessment of the integrity of the hypothalamus-pituitary-gonad axis in young infants. DESIGN: In a nationwide prospective study (1994-1996), patients were referred to our department if neonatal CH screening results were indicative of CH-C. When CH-C was confirmed, GnRH tests and baseline Gn and sex hormone measurements took place at the age of 3 months, when euthyroid status had been accomplished by T4 supplementation, and if necessary, cortisol supplementation was installed. SETTING: The study took place at the Department of Pediatric Endocrinology, Emma Children's Hospital, Academic Medical Center, University of Amsterdam (referral center). PATIENTS: The study included 15 neonates (five girls and 10 boys) with CH-C, detected by neonatal screening, in whom investigation of the hypothalamus-pituitary-gonad axis could be performed at 3 months of age. MAIN OUTCOME MEASURES: Results of GnRH tests and baseline Gn and sex hormone measurements were assessed. RESULTS: GnRH tests at 3 months of age showed a pattern indicative of endogenous GnRH stimulation in nine infants and a blunted response in six. Baseline Gn and sex hormone concentrations except estradiol (P = 0.053) were significantly different between responders and nonresponders. CONCLUSIONS: The GnRH test and baseline measurements of Gn and sex hormone serum concentrations at 3 months of age are promising options in the assessment of hypothalamic-pituitary-gonadal function in infants with CH-C of both sexes.

[A premature infant with increased bleeding tendency: what if the family history of bleeding disorders is negative?]. / Een prematuur met verhoogde bloedingsneiging: wat als de familieanamnese voor stollingsstoornissen negatief is?

BACKGROUND: Haemophilia A is an X-chromosome recessive hereditary disorder and occurs in 1 in 5000 boys. In 30-50% of patients with haemophilia the family history of bleeding disorders is negative. CASE DESCRIPTION: We report on a premature male infant, born at 33 weeks of gestation, who exhibited prolonged bleeding from venipuncture sites the day after birth. The family history was negative for bleeding disorders. Initially he received vitamin K supplementation but, when the bleeding persisted, more detailed diagnostics revealed a prolonged aPTT. Factor VIII activity was 1% of the reference value and the neonate appeared to have a Grade I intraventricular haemorrhage on cerebral ultrasound. He was therefore treated with factor VIII. CONCLUSION: Early recognition and diagnostics in neonates with an increased bleeding tendency is important, even when the family history of bleeding disorders is negative.

Metabolic Health in Short Children Born Small for Gestational Age Treated With Growth Hormone and Gonadotropin-Releasing Hormone Analog: Results of a Randomized, Dose-Response Trial.

CONTEXT: Previously we showed that pubertal children born small for gestational age (SGA) with a poor adult height (AH) expectation can benefit from treatment with GH 1 mg/m(2) per day (∼ 0.033 mg/kg/d) in combination with 2 years of GnRH analog (GnRHa) and even more so with a double GH dose. GnRHa treatment is thought to have negative effects on body composition and blood pressure. Long-term effects and GH-dose effects on metabolic health in children treated with combined GH/GnRHa are unknown. OBJECTIVE: This study aimed to investigate body composition, blood pressure, and lipid profile during GH treatment, either with or without 2 years of additional GnRHa. To assess whether GH 2 mg/m(2) per day (∼ 0.067 mg/kg/d) results in a similar or even more favorable metabolic health at AH than GH 1 mg/m(2) per day. METHODS: This was a longitudinal, randomized, dose-response GH trial involving 107 short SGA children (58 girls) treated with GH until AH (GH randomized 1 or 2 mg/m(2)/d during puberty). Sixty-four children received additional GnRHa. At AH, metabolic parameters were compared between children treated with combined GH/GnRHa and those with only GH. The GH dose effect on metabolic health was evaluated in a subgroup of 47 children who started GH treatment in early puberty (randomized 1 or 2 mg/m(2)/d) with 2 years of GnRHa. RESULTS: At AH, fat mass percentage (FM%) SD score (SDS), lean body mass (LBM) SDS, blood pressure SDS, and lipid profile were similar between children treated with combined GH/GnRHa and those with only GH. In the pubertal subgroup, FM% SDS was lower during treatment with GH 2 mg/m(2) per day. There was no GH dose-dependent effect on LBM SDS, blood pressure, and lipid profile. CONCLUSIONS: Combined GH/GnRHa treatment has no long-term negative effects on metabolic health compared with only GH. Started in early puberty, a GH dose of 2 mg/m(2) per day results in a similar metabolic health at AH and a more favorable FM% than GH 1 mg/m(2) per day.

Adult height in short children born SGA treated with growth hormone and gonadotropin releasing hormone analog: results of a randomized, dose-response GH trial.

CONTEXT: GH treatment is effective in improving height in short children born small for gestational age (SGA). GH is thought to have limited effect when started during adolescence. OBJECTIVE: The aim of this study was to investigate GH treatment efficacy in short SGA children when treatment was started during adolescence; to assess whether GH 2 mg/m(2) · d during puberty improves adult height (AH) compared with 1 mg/m(2) · d; and to assess whether an additional 2-yr postponement of puberty by GnRH analog (GnRHa) improves AH in children who are short at the start of puberty (<140 cm), with a poor AH expectation. PATIENTS AND DESIGN: In this longitudinal, randomized, dose-response GH trial, we included 121 short SGA children (60 boys) at least 8 yr of age. We performed intention-to-treat analyses on all children and uncensored case analyses on 84 children who reached AH. Besides, we evaluated growth during 2 yr of combined GH/GnRHa and subsequent GH treatment until AH in a subgroup of 40 pubertal children with a height of less than 140 cm at the start. RESULTS: Short SGA children started treatment at a median age of 11.2 yr, when 46% had already started puberty. Median height increased from -2.9 at start to -1.7 sd score (SDS) at AH (P < 0.001). Treatment with GH 2 vs. 1 mg/m(2) · d during puberty resulted in significantly better AH (P = 0.001), also after correction for gender, age at start, height SDS at start, treatment years before puberty, and target height SDS. AH was similar in children who started puberty at less than 140 cm and received GH/GnRHa, compared with children who started puberty greater than 140 cm and received GH only (P = 0.795). CONCLUSION: When started in adolescence, GH treatment significantly improves AH in short SGA children, particularly with GH 2 mg/m(2) · d during puberty. When SGA children are short at the start of puberty, they can benefit from combined GH/GnRHa treatment.

Beneficial effects of growth hormone treatment on cognition in children with Prader-Willi syndrome: a randomized controlled trial and longitudinal study.

BACKGROUND: Knowledge about the effects of GH treatment on cognitive functioning in children with Prader-Willi syndrome (PWS) is limited. METHODS: Fifty prepubertal children aged 3.5 to 14 yr were studied in a randomized controlled GH trial during 2 yr, followed by a longitudinal study during 4 yr of GH treatment. Cognitive functioning was measured biennially by short forms of the WPPSI-R or WISC-R, depending on age. Total IQ (TIQ) score was estimated based on two subtest scores. RESULTS: During the randomized controlled trial, mean sd scores of all subtests and mean TIQ score remained similar compared to baseline in GH-treated children with PWS, whereas in untreated controls mean subtest sd scores and mean TIQ score decreased and became lower compared to baseline. This decline was significant for the Similarities (P = 0.04) and Vocabulary (P = 0.03) subtests. After 4 yr of GH treatment, mean sd scores on the Similarities and Block design subtests were significantly higher than at baseline (P = 0.01 and P = 0.03, respectively), and scores on Vocabulary and TIQ remained similar compared to baseline. At baseline, children with a maternal uniparental disomy had a significantly lower score on the Block design subtest (P = 0.01) but a larger increment on this subtest during 4 yr of GH treatment than children with a deletion. Lower baseline scores correlated significantly with higher increases in Similarities (P = 0.04) and Block design (P < 0.0001) sd scores. CONCLUSIONS: Our study shows that GH treatment prevents deterioration of certain cognitive skills in children with PWS on the short term and significantly improves abstract reasoning and visuospatial skills during 4 yr of GH treatment. Furthermore, children with a greater deficit had more benefit from GH treatment.

Does sampling site influence levels of free thyroxine and thyrotropin determined by a current immunoassay?

OBJECTIVES: To examine the effect of sampling site on levels of free thyroxine (fT4) and thyrotropin (TSH). DESIGN AND METHODS: fT4 and TSH were determined by a current immuno-assay in paired samples of capillary and venous blood drawn from 30 euthyroid adults. RESULTS: Mean levels of fT4 and TSH did not differ significantly between capillary and venous blood; capillary and venous levels correlated well and did not differ significantly from unity. CONCLUSIONS: Sampling site does not influence levels of fT4 and TSH.

Mutations in CCBE1 cause generalized lymph vessel dysplasia in humans.

Lymphedema, lymphangiectasias, mental retardation and unusual facial characteristics define the autosomal recessive Hennekam syndrome. Homozygosity mapping identified a critical chromosomal region containing CCBE1, the human ortholog of a gene essential for lymphangiogenesis in zebrafish. Homozygous and compound heterozygous mutations in seven subjects paired with functional analysis in a zebrafish model identify CCBE1 as one of few genes causing primary generalized lymph-vessel dysplasia in humans.

Efficacy and safety of long-term continuous growth hormone treatment in children with Prader-Willi syndrome.

BACKGROUND: Children with Prader-Willi syndrome (PWS) have abnormal body composition and impaired growth. Short-term GH treatment has beneficial effects. OBJECTIVES: The aim of the study was to investigate effects of long-term continuous GH treatment on body composition, growth, bone maturation, and safety parameters. SETTING: We conducted a multicenter prospective trial. DESIGN: Fifty-five children with a mean +/- sd age of 5.9 +/- 3.2 yr were followed during 4 yr of continuous GH treatment (1 mg/m(2) . d). Data were annually obtained in one center: fat percentage (fat%) and lean body mass (LBM) by dual-energy x-ray absorptiometry, height, weight, head circumference, bone age, blood pressure, and fasting IGF-I, IGF binding protein-3, glucose, insulin, glycosylated hemoglobin, total cholesterol, high-density lipoprotein, and low-density lipoprotein. sd scores (SDS) were calculated according to Dutch and PWS reference values (SDS and SDS(PWS)). RESULTS: Fat%SDS was significantly lower after 4 yr of GH treatment (P < 0.0001). LBMSDS significantly increased during the first year (P = 0.02) but returned to baseline values the second year and remained unchanged thereafter. Mean +/- sd height normalized from -2.27 +/- 1.2 SDS to -0.24 +/- 1.2 SDS (P < 0.0001). Head circumference SDS increased from -0.79 +/- 1.0 at start to 0.07 +/- 1.1 SDS after 4 yr. BMISDS(PWS) significantly decreased. Mean +/- sd IGF-I and the IGF-I/IGF binding protein-3 ratio significantly increased to 2.08 +/- 1.1 and 2.32 +/- 0.9 SDS, respectively. GH treatment had no adverse effects on bone maturation, blood pressure, glucose homeostasis, and serum lipids. CONCLUSIONS: Our study in children with PWS shows that 4 yr of continuous GH treatment (1 mg/m(2) . d) improves body composition by decreasing fat%SDS and stabilizing LBMSDS and head circumference SDS and normalizes heightSDS without adverse effects. Thus, long-term continuous GH treatment is an effective and safe therapy for children with PWS.