RESUMEN
Recombinant human growth hormone (rhGH) treatment is an established management in patients with Prader-Willi syndrome (PWS), with growth promotion and improvement in body composition and possibly the metabolic state. We compared anthropometric characteristics, insulin-like growth factor 1 (IGF1) levels, metabolic parameters and the bone age/chronological age index (BA/CA) in 147 children with PWS, divided according to age of rhGH start into four groups, corresponding to nutritional phases in PWS. We analysed four time points: baseline, rhGH1 (1.21 ± 0.81 years), rhGH2 (3.77 ± 2.17 years) and rhGH3 (6.50 ± 2.92 years). There were no major differences regarding height SDS between the groups, with a higher growth velocity (GV) (p = 0.00) and lower body mass index (BMI) SDS (p < 0.05) between the first and older groups during almost the whole follow-up. IGF1 SDS values were lower in group 1 vs. other groups at rhGH1 and vs. groups 2 and 3 at rhGH2 (p < 0.05). Glucose metabolism parameters were favourable in groups 1 and 2, and the lipid profile was comparable in all groups. BA/CA was similar between the older groups. rhGH therapy was most effective in the youngest patients, before the nutritional phase of increased appetite. We did not observe worsening of metabolic parameters or BA/CA advancement in older patients during a comparable time of rhGH therapy.
RESUMEN
Genotype-phenotype correlation in patients with Prader-Willi syndrome (PWS) has still not been fully described. We retrospectively analysed data of 147 patients and compared groups according to genetic diagnosis: paternal deletion of chromosome 15q11-q13 (DEL 15, n = 81), maternal uniparental disomy (UPD 15, n = 10), excluded DEL 15 (UPD 15 or imprinting centre defect, UPD/ID, n = 30). Group DEL 15 had an earlier genetic diagnosis and recombinant human growth hormone (rhGH) start (p = 0.00), with a higher insulin-like growth factor 1 (IGF1) level compared to group UPD/ID (p = 0.04). Among perinatal characteristics, there was only a tendency towards lower birth weight SDS in group UPD 15 (p = 0.06). We also compared data at rhGH start in relation to genetic diagnosis age-group 1: age ≤9 months, group 2: >9 months ≤ 2 years, group 3: > 2 years. Group 1 had the earliest rhGH start (p = 0.00), with lower body mass index (BMI) SDS (p = 0.00) and a tendency towards a higher IGF1 level compared to group 3 (p = 0.05). Genetic background in children with PWS is related to time of diagnosis and rhGH start, with a difference in IGF1 level before the therapy, but it seems to have little impact on perinatal data. Early genetic diagnosis leads to early rhGH treatment with favourable lower BMI SDS.
RESUMEN
BACKGROUND: The morphological and biochemical phenotype of PAX8 mutation in patients with congenital hypothyroidism (CH) is variable. The contribution of mutations in PAX8 gene in children with CH and dysgenetic thyroid glands still remains a subject of interest for researchers. PATIENTS AND METHODS: Some 48 children (37 girls and 11 boys) with CH associated with thyroid ectopy (n=22), agenesis (n=10), hypoplasia (n=6), or thyroid dysgenesis of unknown cause (n=10) were enrolled. The study participants were born in south-eastern Poland in the years 1993-2012 and were selected for neonatal mass screening for CH. DNA was extracted from peripheral blood samples using Master Pure DNA Purification Kit (Epicentre Biotechnologies, Madison, WI, USA). The 12 exons of the PAX8 gene along with their exon-intron boundaries were amplified and sequenced by the Sanger method. Capillary electrophoresis was run on ABI 3500 (Applied Biosystems, Carlsbad, CA, USA). RESULTS: Novel heterozygous transition in exon 3 (c.68G>A) was detected in a 3-year-old girl with a thyroid hypoplasia. This substitution was not identified in the patient's parents (de novo event). Additionally, a novel genetic variant in 3'UTR region of exon 12 (c.*416C>T) occurred in a 3-year-old boy with ectopic thyroid tissue and concomitant congenital urogenital malformation. This heterozygous variant was also detected in other healthy family members. Thirteen well-described single nucleotide polymorphisms were revealed in the PAX8 gene. CONCLUSIONS: The study reports on the occurrence of two novel heterozygous substitutions in the PAX8 gene. Estimation of the contribution of the revealed c.68G>A variant to the etiology of CH in a girl with hypoplastic thyroid requires further functional analysis.
