Physiological growth hormone secretion during slow-wave sleep in short prepubertal children

Crescimento pôndero-estatural de crianças após adenoamigdalectomia

A hiperplasia adenoamigdaliana é a principal causa de obstrução das vias aéreas superiores em crianças, sendo muitas vezes associada à apnéia do sono. Esta, por sua vez, resulta em uma série de comprometimentos: baixo rendimento escolar, cor pulmonale, distúrbios de comportamento não específicos, hiperatividade, sonolência diurna, distração e atrasos de desenvolvimento, sendo o déficit pôndero-estatural o mais grave. A adenoamigdalectomia é o tratamento de escolha. O objetivo deste trabalho é mensurar o crescimento e desenvolvimento das crianças antes e depois da adenoamigdalectomia através da comparação dos percentis pré e pós operatórios. FORMA DE ESTUDO: Clínico prospectivo randomizado. MATERIAL E MÉTODO: Cinquenta e cinco crianças de 2 a 12 anos, com história de obstrução das vias aéreas superiores por hiperplasia adenoamigdaliana foram submetidas a exame antropométrico (peso e altura), antes e 6 meses após a adenoamigdalectomia. Os dados foram transformados em percentil para peso e altura, de acordo com a idade e comparados através de análise estatística. RESULTADOS: No pré-operatório, encontramos a seguinte distribuição para o percentil altura: 78,2%, abaixo de p75 e para peso 70,9% abaixo de p50. No pós-operatório observou-se melhor distribuição das crianças: para altura 34,6% abaixo de p75, 32,8% entre p75-95 e 32,6% para p95 e acima e para peso: 35,5% abaixo de p50, 36,4% para p50-95 e 29,1% acima de p95. CONCLUSÃO: Observou-se uma melhora considerável do desenvolvimento pôndero-estatural das crianças após a adenoamigdalectomia.

Intensive diabetes management in pediatric patients

Intensive diabetes management requires frequent home glucose monitoring, multiple daily insulin injections or chronic subcutaneous insulin infusion, and adjustments of insulin doses in response to changes in blood glucose levels, food intake, and exercise. It also requires a periodic review of previous glucose results to recognize patterns of hyper- or hypoglycemia. The goals of intensive management are age dependent. In young children, avoidance of severe hypoglycemia is the major goal. In older children and adolescents, lowering hemoglobin A(1c) becomes an increasingly important goal. In children of all ages, the ability to have a flexible lifestyle and meal plan is often a priority. This article provides a brief overview of the rationale for implementing intensive diabetes management in pediatric patients, and practical guidelines for implementation.

Development and evaluation of a direct immunofluorimetric assay for urinary growth hormone

We describe a two-site immunofluorimetric assay for urinary growth hormone that is resistant to interference from a wide range of urinary constituents and therefore eliminates the need for sample pre-treatment. A microtitre plate format is used with specific orientation of capture antibody on a polystyrene surface carrying a hydrazide group. Europium-labelled F(ab)2 is the fluorophore and time-resolved fluorimetry with co-fluorescence enhancement the signal detection system. Inter-assay precision was 11.3% at 5.2 ng/L and 10.3% at 44.3 ng/L, minimum detection limit (22% coefficient of variation, CV) was < 1.0 ng/L, working range (< 10% CV) was 0-100 ng/L and quantitative recovery and good parallelism were demonstrated. This convenient and sensitive assay is suitable for the routine measurement of human growth hormone (hGH) in urine.

The reproducibility of urinary growth hormone measurement in children undergoing adenotonsillectomy: a pilot study

The reproducibility of urinary growth hormone levels in normal children and in children undergoing adenotonsillar surgery was investigated. Thirty normal children and 32 children pre- and post-adenotonsillectomy had overnight urinary growth hormone levels measured on two consecutive nights using the technique of immunoradiometric assay. There was no significant difference when levels in each of these groups were compared. Therefore, the results were pooled (n = 94) and the correlation coefficient comparing levels obtained on the first and the second consecutive nights sample was calculated, r = 0.644 (P < 0.001). This work suggests that studies of urinary growth hormone levels in children give reproducible results. Further investigation of this technique as a screening or diagnostic procedure in the clinical setting can now be more widely evaluated.

The assessment of pituitary function

The assessment of pituitary function can now be carried out quickly and accurately by means of outpatient testing procedures and hormone immunoassays. Improvements in assay methodology have resulted in greater specificity and sensitivity although some technical problems remain. The diagnosis of patients with functioning and nonfunctioning pituitary tumors, hypopituitarism and target gland disorders is discussed with particular reference to diagnostic difficulties and recent advances.

Physiological growth hormone secretion and response to growth hormone treatment in children with short stature and intrauterine growth retardation

Physiological growth hormone (GH) secretion was examined in 31 children (8 girls, 23 boys) with short stature secondary to intrauterine growth retardation (IUGR). Seventeen (4 girls, 13 boys) had dysmorphic features of Russell-Silver syndrome. Four of the 31 children had GH insufficiency with peak GH levels of less than 20 mU/l during the night. Nine of the patients (8 of whom had Russell-Silver syndrome) had a single nocturnal GH pulse. Twenty-three children (6 girls, 17 boys) were randomized into two groups treated with either 15 or 30 U/m2/week of GH by daily subcutaneous injections. Age, sex distribution, pretreatment height velocity SD score (SDS), and distribution of dysmorphic and non-dysmorphic children were similar in both groups. The group treated with 15 U/m2/week for a mean of 0.82 years showed an increase in mean height velocity SDS from -0.61 to +1.09, and the group treated with 30 U/m2/week for a mean of 0.92 years showed an increase in mean height velocity SDS from -0.69 to +3.48. The results suggest that physiological GH insufficiency is probably common in children with Russell-Silver syndrome and that both dysmorphic and non-dysmorphic children with short stature secondary to IUGR will respond to GH treatment. Initial evidence suggests that the increase in short-term growth velocity does not result in an improved final height prognosis.

Physiological growth hormone (GH) secretion during the recovery from psychosocial dwarfism: a case report

We describe a 6.4 year old boy who had reversible GH insufficiency secondary to psychosocial dwarfism. On removal to a more favourable environment we observed the recovery of physiological GH secretion by progressive increase in GH pulse amplitude. These observations are relevant to our understanding of the control of GH secretion in that GH pulse frequency appears invariable and alteration in GH secretion is by pulse amplitude modulation.