Función gonadal en niños y adolescentes nacidos con restricción del crecimiento intrauterino / Gonadal function in children and adolescents born with restriction of intrauterine growth

Los niños con restricción del crecimiento intrauterino (RCIU) presentan en la vida posnatal una serie de alteraciones metabólicas y hormonales, y tienen predisposición al desarrollo de obesidad, hipertensión arterial, enfermedad cardiovascular, resistencia a la insulina y diabetes tipo 2. La exposición a un ambiente intrauterino desfavorable en fases críticas del desarrollo puede tener un efecto deletéreo sobre la gónada en formación. Se realizó una revisión bibliográfica y puesta al día sobre la posible asociación entre RCIU y alteraciones de la función gonadal en niños y adolescentes de ambos sexos. Para facilitar la actualización, se dividió por etapas en: 1, prenatal; 2, posnatal y prepuberal; 3, puberal, y 4, adulta. La mayoría de los niños que nacen muy prematuros o con muy bajo peso al nacer hacen una transición sin obstáculos desde la infancia a la edad adulta con respecto a la salud reproductiva. Sin embargo, en los varones se puede observar criptorquidia, hipospadias, cáncer testicular y menor fertilidad, y en las niñas, pubertad y menarca temprana, hiperandrogenismo y síndrome de ovario poliquístico. Existen datos controvertidos y se necesitan más estudios para aclarar la relación entre el RCIU y la función hipotálamo-hipófiso-gonadal.

Low birth weight due to intrauterine growth restriction (IUGR) is associated with an increased risk of obesity, hypertension, cardiovascular disease, insulin resistance, and type 2 diabetes during postnatal life. Exposure to an unfavourable intrauterine environment in critical phases of development may have a deleterious effect on the forming gonad. The objective was to carry out a bibliographic review and update on the possible association between IUGR and alterations of gonadal function in children and adolescents of both sexes. To facilitate the update, this was divided into stages: 1, prenatal; 2, postnatal and pre-pubertal; 3, puberal, and 4, adult. Most children born preterm or with low birth weight make a normal transition from childhood to adulthood with respect to reproductive health. However, cryptorchidism, hypospadias, testicular cancer and lower fertility could be observed in boys, and early puberty and menarche, hyperandrogenism and polycystic ovarian syndrome in girls. However, the data are controversial, and further studies are needed to clarify the relationship between IUGR and pituitary gonadal function.

Male-female differences in 6-sulfatoxymelatonin excretion in hypopituitary patients

ABSTRACT Objective To evaluate melatonin secretion in adult hypopituitary patients with Growth Hormone deficiency (AGHD) on and off replacement therapy. Subjects and methods We studied 48 subjects: 12 (6 males) untreated AGHD (AGHDnt), 20 (10 males) treated AGHD (AGHDt) and 16 healthy subjects (8 males) as control group (CG). We measured urinary 6-sulfatoxymelatonin (6-SM) in total (24 h samples), nocturnal (6-SMn): 1800-0800 and diurnal samples (6-SMd): 0800-1800. Results Significant differences were observed among the 3 groups of male subjects, in total 6-SM (p < 0.05), nocturnal 6-SM (p < 0.02) and nighttime-daytime delta values (p < 0.003). CG had significantly higher values than the AGHDnt in total 6-SM (p < 0.01), nocturnal 6-SM (p < 0.05) and nighttime-daytime delta values (p < 0.01). AGHDt patients showed significantly higher levels in nighttime-daytime delta values than AGHDnt patients (p < 0.05). In females, no significant differences were found among the 3 groups studied in total, nocturnal, diurnal or nighttime-daytime delta values. In males, significant correlations were found among total 6-SM (r = 0.58; p = 0.029), nocturnal 6-SM (r = 0.70; p = 0.006) and nighttime-daytime delta values (r = 0.71; p = 0.004) vs. serum IGF-1 levels in subjects evaluated. In females, significant correlations were found among total 6-SM (r = 0.57; p = 0.02) vs. serum IGF-1 levels in subjects evaluated. A tendency towards a significant correlation was found in diurnal 6-SM (r = 0.48; p = 0.07). Conclusions Our findings show a sexual dimorphism in 6-SM excretion in AGHD patients and provide an interesting approach to a further understanding of some chronobiological disorders involved in GH deficiency.

Burden of Growth Hormone Deficiency and Excess in Children.

Longitudinal growth results from multifactorial and complex processes that take place in the context of different genetic traits and environmental influences. Thus, in view of the difficulties in comprehension of the physiological mechanisms involved in the achievement of normal height, our ability to make a definitive diagnosis of GH impairment still remains limited. There is a myriad of controversial aspects in relation to GH deficiency, mainly related to diagnostic controversies and advances in molecular biology. This might explain the diversity in therapeutic responses and may also serve as a rationale for new "nonclassical" treatment indications for GH. It is necessary to acquire more effective tools to reach an adequate evaluation, particularly while considering the long-term implications of a correct diagnosis, the cost, and safety of treatments. On the other hand, overgrowth constitutes a heterogeneous group of different pathophysiological situations including excessive somatic and visceral growth. There are overlaps in clinical and molecular features among overgrowth syndromes, which constitute the real burden for an accurate diagnosis. In conclusion, both GH deficiency and overgrowth are a great dilemma, still not completely solved. In this chapter, we review the most burdensome aspects related to short stature, GH deficiency, and excess in children, avoiding any details about well-known issues that have been extensively discussed in the literature.

Male-female differences in 6-sulfatoxymelatonin excretion in hypopituitary patients.

OBJECTIVE: To evaluate melatonin secretion in adult hypopituitary patients with Growth Hormone deficiency (AGHD) on and off replacement therapy. SUBJECTS AND METHODS: We studied 48 subjects: 12 (6 males) untreated AGHD (AGHDnt), 20 (10 males) treated AGHD (AGHDt) and 16 healthy subjects (8 males) as control group (CG). We measured urinary 6-sulfatoxymelatonin (6-SM) in total (24 h samples), nocturnal (6-SMn): 1800-0800 and diurnal samples (6-SMd): 0800-1800. RESULTS: Significant differences were observed among the 3 groups of male subjects, in total 6-SM (p < 0.05), nocturnal 6-SM (p < 0.02) and nighttime-daytime delta values (p < 0.003). CG had significantly higher values than the AGHDnt in total 6-SM (p < 0.01), nocturnal 6-SM (p < 0.05) and nighttime-daytime delta values (p < 0.01). AGHDt patients showed significantly higher levels in nighttime-daytime delta values than AGHDnt patients (p < 0.05). In females, no significant differences were found among the 3 groups studied in total, nocturnal, diurnal or nighttime-daytime delta values. In males, significant correlations were found among total 6-SM (r = 0.58; p = 0.029), nocturnal 6-SM (r = 0.70; p = 0.006) and nighttime-daytime delta values (r = 0.71; p = 0.004) vs. serum IGF-1 levels in subjects evaluated. In females, significant correlations were found among total 6-SM (r = 0.57; p = 0.02) vs. serum IGF-1 levels in subjects evaluated. A tendency towards a significant correlation was found in diurnal 6-SM (r = 0.48; p = 0.07). CONCLUSIONS: Our findings show a sexual dimorphism in 6-SM excretion in AGHD patients and provide an interesting approach to a further understanding of some chronobiological disorders involved in GH deficiency.

Decreased 6-Sulfatoxymelatonin Excretion in Male GH-Deficient Children and Adolescents.

AIM: To evaluate melatonin secretion in a group of untreated and treated male growth hormone (GH)-deficient children and adolescents. METHODS: We studied 44 male subjects: 8 untreated GH-deficient patients (GHDnt), 16 treated GH-deficient patients (GHDt) and 20 healthy children and adolescents as control group (CG). We measured urinary 6-sulfatoxymelatonin (6-SM) in total (24-hour samples), nocturnal (18.00-8.00 h) and diurnal samples (8.00-18.00 h). Levels of 6-SM were expressed as micrograms excreted per time interval and x0394; values (difference between nighttime and daytime values). RESULTS: Significant differences were observed among the 3 groups of pediatric subjects studied for total 6-SM (p < 0.0001), nocturnal 6-SM (p < 0.0001) and x0394; values (p < 0.0001). Subsequent analysis showed significantly higher levels for total 6-SM, nocturnal 6-SM and nighttime-daytime x0394; in the CG versus the GHDnt (p < 0.01) and in the CG versus the GHDt group (p < 0.01). No significant correlations were found between 6-SM excretion and insulin-like growth factor-1 values in the children and adolescents studied. CONCLUSIONS: GH-deficient patients showed lower levels of 6-SM. Our findings provide a different insight to a further understanding of some chronobiological disorders involved in GH deficiency in children.

Effect of the parental origin of the X-chromosome on the clinical features, associated complications, the two-year-response to growth hormone (rhGH) and the biochemical profile in patients with turner syndrome.

BACKGROUND: It is possible that genes on the X chromosome are expressed differently depending of its parental origin. The objective of this study was to determine the influence of the parental origin of the X-chromosome on phenotypic variability, response to rhGH and on the biochemical profile of TS patients. METHODS: This was a cross-sectional multicenter correlational study carried out over three years in six Latin-American university hospitals. Unrelated 45,X TS patients (n = 93; 18.3 ± 8.5 years )) were evaluated. A subgroup (n = 34) of the patients were prospectively treated with rhGH over two years. DNA profiles of patients and their mothers were compared to determine the parental origin of the retained X-chromosome through 10 polymorphic X-chromosome-STRs. The association with clinical features, biochemical profiles and anthropometric data at the beginning and after two years of rhGH treatment was determined. RESULTS: Seventy two percent of patients retained the maternal X chromosome (Xm). A trend towards significance between maternal height and patients final height (p ≤ 0.07) in 45,Xm subjects was observed. There was no correlation between paternal height and patient height. No differences were detected between both groups in regard to dysmorphic features, classical malformations or increase in the height-SDS after rhGH. There were higher levels of triglycerides, total and LDL cholesterol in patients >20 years who retained the Xm. CONCLUSIONS: The parental origin of the retained X chromosome may influence lipid metabolism in TS patients, but its effect on growth seems to be minimal. No parental-origin-effect on the phenotypic features, associated anomalies and on the growth response to rhGH was found in 45,X TS individuals.

Tumoral versus non-tumoral hyperprolactinemia in children and adolescents: possible usefulness of the domperidone test.

UNLABELLED: The aim of this study was to evaluate the usefulness of the domperidone test for the difficult diagnosis between functional and tumoral hyperprolactinemia. We evaluated 36 patients, aged 5-18 years, 14 (12 F, 2 M) with hyperprolactinemia (non-tumoral: 10; pituitary adenoma: 4) and 22 individuals as a control group (prepubertal: 5 F, 8 M; pubertal: 4 F, 5 M). Basal prolactin (PRL) (IRMA-DPC), T4 and TSH and PRL 30 min post-domperidone (0.2 mg/kg b. wt i.v.) were measured. Non-tumoral hyperprolactinemic females showed basal PRL: 45 (29-80) (median and range) ng/ml; post-domperidone: 208 (116-290) ng/ml; delta PRL (PRL 30' - PRL 0'): 167 (77-252) ng/ml; and PRL ratio (PRL 30'/PRL 0'): 3.9 (2.3-7.6). Females with pituitary adenoma showed basal PRL: 129 (125-660) ng/ml; post-domperidone: 202 (150-535) ng/ml; delta PRL: 73 (25-135) ng/ml; and ratio: 1.2 (0.8-1.6). Two males, one with a non-tumoral hyperprolactinemia and the other one with a pituitary adenoma, presented, respectively, PRL 0':45, 160; PRL 30':130, 173; delta: 85, 13; ratio: 2.9, 1.1. All non-tumoral patients showed a PRL ratio (30'/0') > 2.3, while no patient with pituitary adenoma had a ratio > 1.6. CONCLUSIONS: PRL response to domperidone allowed us to characterize hyperprolactinemias, although the presence of a blunted response should be confirmed in a larger number of patients with tumors with 'low' PRL levels (dependence on etiology or basal PRL level?).

Utilizacion de un analogo de LH-RH subcutaneo e intranasal en el tratamiento de niñas con pubertad precoz central / Use of a LH-RH analogue subcutaneously and intranasally in the treatment of girls with central precocious puberty

Se presenta la experiencia en 5 pacientes de sexo feminino. Sus edades cronológicas oscilaron entre 1,3 y 6,8 años, con edades óseas entre 2,3 y 11,6 años. Las dosis empleadas fueron: 25 microng/kg/dSC y posteriormente 1200 microng/dIN. En 2 niñas se administraron 159 mg de medroxiprogesterona previo al análogo y una semana después. En un caso, se comenzó por via IN por reacción alérgica local a la inyección SC. El tratamiento osciló entre 3 y 21 meses. Se obtuvo una regreión completa del desarrollo mamario en 4 pacientes y parcial en 1. En 4/5 casos se pudo valorar la velocidad de crecimiento anual, observándose una reducción entre el 40 y 55% vs. pretratamiento, asociada a desaceleración de la maduración ósea y a un incremento entre 2 y 4,5cm en la predicción de talla adulta. Durante la terapéutica se obtuvo una reducción de los niveles de LH, FSH y estradiol hasta valores prepuberales, así como una ausencia de respuesta en la prueba de LH-RH. Concluímos que el Buserelin constituiría en recurso altamente efectivo en el tratamiento de esta patoloía, siendo, al igual que otros análogos del LH-RH, recursos útiles que mejorarian la predicción de talla final