Santiago Muzzo

Variaciones del índice de masa corporal (IMC) de acuerdo al grado de desarrollo puberal alcanzado

BACKGROUND Body mass index (BMI) is the recommended parameter to assess the nutritional status of subjects aged less than 20 years. However, during puberty the correlation between BMI and fat mass decreases notably. Therefore, the use of BMI for the diagnosis of obesity during puberty may be misleading. AIM To evaluate the variations of the BMI during puberty according to chronological and biological ages. MATERIAL AND METHODS Descriptive cross sectional study in school age children of elementary and high schools (4,531 males and 5,326 females) representing all socioeconomic strata of 4 regions of Chile. BMI was calculated from weight and height measurements (W/H2) and pubertal development was evaluated according to Tanner stages. The sample selected to evaluate the variations of BMI according to chronological age and pubertal stages consisted in 3,913 females aged 8-14 years and 2,494 males aged 10-16 years. Analyses of variance (F test) and Tukey HSD test were used to compare mean BMI according to chronological and biological ages. RESULTS The age of onset of puberty (Tanner Stages IB2 and G2) varied greatly, from 8 to 14 years in females and 10 to 16 years in males. Mean BMI in a specific stage of pubertal development did not show significant differences according to age in both sexes. However, there were significant differences (p < 0.05) in mean BMI when comparing children of the same chronological age but in different Tanner stages. Per each stage of Tanner development, BMI increased 1.0 or more points among females and 0.6 points among males. CONCLUSIONS During puberty, BMI is associated to biological and not chronological age.

The hypothalamic-pituitary-adrenal axis in infantile malnutrition.

We studied the circadian rhythm and the response of the hypothalamic‐pituitary‐adrenal (HPA) axis to ovine corticotrophin releasing hormone (oCRH) stimulation and dexamethasone suppression in 32 children with grade II‐III marasmus. Children were studied prior to and after nutritional rehabilitation. Mean baseline plasma cortisol concentrations were elevated at admission and decreased significantly after nutritional rehabilitation. Mean±SEM plasma cortisol response to oCRH increased from a basal of 480 ±41 to a peak of 582 ± 58 nmol/1 at the time of admission, and from a basal of 234±27 to a peak of 532±41 nmol/1 after caloric rehabilitation. Dexamethasone suppression in the malnourished group was associated with a decrease in the mean±SEM basal plasma cortisol concentration from 397±44 to 171 ±44 nmol/1. After caloric rehabilitation, basal cortisol levels decreased from 259±27 to 22±5 nmol/l following dexamethasone. Our results support the concept that malnutrition is associated with decreased responsiveness to oCRH and incomplete dexamethasone suppression, and that these abnormalities are restored after nutritional rehabilitation.

Effect of calcium and vitamin D supplementation on bone mineral density of celiac children

Abstract We were interested in detecting the changes in bone mineral density (BMD) in prepuberal and puberal celiac children after 24 months of supplementation with 1000 mg of calcium and 400 U of vitamin D daily. 19 celiac children (16 females, and 3 males, age 6 to 15 years) with good compliance to the gluten free diet for at least two years, paired with 19 healthly children of the same age and sex were studied. Celiac patients had mean calcium intakes of 739 mg per day, that increased to 1444 mg per day after nutritional supplementation, with 84 and 74% of compliance during the first and second years of supplementation. Celiac patients did not show significant changes in stature and nutritional status during supplementation. The whole group of celiac subjects showed a significant increase in z score of WB-BMD and FN-BMD from the start and until 24 months of supplementation, compared to the controls (WB-BMD: −0.24±0.40 and −0.80±0.59 vs 0.49±0.62 and 0.62±0.83. FN-BMD:−0.41±0.96 and 0.04±1.12 vs 0.58±1.29 and 0.36±1.15 respectively) Total group and pubertal celiac patients showed a significantly greater variation (delta z score) of hip BMD (FN-BMD 0.53 ± 0.85 p

Histological maturation of astroglial cells in the archicortex of early malnourished rats.

Summary: The maturation of fibrous astrocytes was studied in the archicortex (hippocampus) of rats subjected to early postnatal malnutrition. A decrease in the number of protoplasmic processes and end-feet in fibrous astrocytes from the cortical molecular layer was observed. In animals refed after weaning the number of protoplasmic processes returned to normal while that of end-feet remained unchanged. The diameter of the perikaryon was reduced. It is postulated that early malnutrition, induced immediately after birth, impairs differentiation of astroglia in the archicortex of the rat brain, probably as a response secondary to altered neuronal and capillary development.Speculation: The effect of early postnatal malnutrition is most severe in structures of the central nervous system which have the highest rates of growth and differentiation. Important, and sometimes lifelong, changes in brain structure and composition including neuronal damage have been demonstrated.This study indicates that astroglial cells are also adversely affected by prolonged nutrient deprivation. These cells participate in neuronal metabolism and damage to them may contribute to intensify the effects of malnutrition upon the neurons.

BONE MINERAL DENSITY (BMD) IN CHILDREN WITH CELIAC DISEASE (CD): ITS RELATION TO PUBERTY AND CALCIUM INTAKE

Abstract Bone mineral density (BMD) and calcium intake were studied in 39 celiac patients (CP) with good compliance for the gluten free diet in 39 healthy subjects, aged 6 to 16 years of age (17 prepuberal and 22 puberal) in a case-control design (1;1). Nutritional and statural adequacy were evaluated by means of the body mass index (BMI), and height for age (H/A) respectively, expressed as z score. BMD in the whole body, spine and hip was evaluated using a LUNAR densitometer in prepuberal and as puberal CD. Food intake was determined by 24 hours recall. Antiendomisium and anti-gliadin antibodies and bone age were also evaluated. Statural adequacy of celiacs was significantly lower (p

Influence of the severity of infantile malnutrition on plasma growth hormone levels

Abstract Early postnatal undernutrition induces hormonal alternations. High levels of human growth hormone (hGH) have been described in undernourished infants. The effect of the severity of malnutrition upon plasma hGH levels has been studied. It was found that the more severe the undernutrition the higher the basal hGH levels and the lower the hGH response to L-dopa stimulation. It is concluded that even mild forms of undernutrition cause alterations in the metabolism of hGH, and/or in some other aspects of the physiological mechanisms in which this hormone normally plays a role.

The growth hormone response to growth hormone-releasing hormone stimulation in infantile protein-calorie malnutrition

Abstract Growth hormone kinetics in infantile malnutrition are characterized by high basal values and decreased responses to various provocative stimuli. The mechanism of this alteration has not been explained. To determine whether altered sensitivity to growth hormone releasing hormone (GHRH) plays a role in this phenomenon, we perfomed GHRH testing in 19 infants with primary malnutrition of grades II and III before and after 6 weeks of nutritional rehabilitation. GHRH (1–44) NH2 was administered intravenously by bolus injection at a dose of 1 mcg/kg. Mean baseline GH maximum elevation above baseline (ΔGH), and area under the Gh response curve (Σ GH) were measured. The injections stimulated a rapid rise in GH which reached a maximum at 15–30 mins after GHRH. There were no significant differences in the magnitude or time couse of the responses between infants in the malnourished and recovering states (Δ GH 29±7 vs. 34±5 ng ml:Σ GH 3379±571 vs. 3459±397 ng. min/ml respectively), and responses were similar to thoses of normal prepuberal children. We conclude that altered sensitivity of pituitary to GHRH appears not to underlie the alterations of growth hormone dynamics observed in malnutrion.

Niveles plasmáticos de vitamina D e ingesta de calcio en niños celiacos: factores de riesgo para su salud futura

Objetivo: Evaluar los niveles plasmaticos de vitamina D y la ingesta de calcio en pacientes celiacos. Material y Metodo: 25 pacientes celiacos (20 mujeres y 5 hombres, de 5 a 15 anos de edad) con una buena adhesion al regimen libre de gluten de al menos los dos ultimos anos. La ingesta de calcio se evaluo mediante tres encuestas de recordatorio de 24 horas. La 25 OH vitamina D se determino mediante RIA (INCSTAR). Resultados: Un 80% de los pacientes presento una ingesta de calcio insuficiente de acuerdo al consenso del NIH; en los menores de 10 anos la ingesta promedio fue de 866 ( 423 y en los mayores de 11 anos 605 ( 237 mg/dia. Se encontro deficit de vitamina D (<37.5 nmol/L o 15 ng/mL) en 5 de los casos (20%), de los cuales 4 corresponden a muestras tomadas en invierno y una en verano. En dos casos el deficit fue severo <20 nmoles/L (<8 ng/ml). Conclusion: En pacientes celiacos evaluados la hipovitaminosis D y la ingesta insuficiente de calcio fueron situaciones frecuentes, lo que puede producir el deficit de masa osea detectado en estos pacientes y facilitar el desarrollo futuro de osteoporosis y diabetes. Se recomienda evaluar los niveles de vitamina D y la ingesta de calcio como parte del control de estos pacientes y en caso necesario efectuar una suplementacion con calcio y vitamina D

High Affinity Estrogen Receptors in Uterus of Early Malnourished Rats

We have found that marasmic malnutrition in rats permanently decreases uterine cell number. On the other hand, a decrease of total plasma estrogen levels in mothers of small for gestational age newborns has been demonstrated. We have found, also, decreased levels of sex hormone binding globulin in these mothers, suggesting lower levels of free plasma estrogens. As an index of hormone action upon the target cells, we studied uterine estradiol receptors of early malnourished rats. Malnutrition was induced in rats by increasing litter size to 18 pups per dam from birth until weaning. These offspring received a 22% protein diet from days 21–90 of life. Control dams nursed 6 pups, which were fed the normal diet after weaning; all animals were killed at 90 days. Uterine estradiol receptors were measured according to the technique of Feherty et al., recovering bound estradiol with DEAE-cellulose filters instead of dextran-charcoal. Estradiol binding capacity of the uteri of marasmic rats was decreased compared to normal, age-matched controls expressed as picomoles per mg tissue (8.26 ± 2.76 × 10−4 vs. 5.16 ± 1.96 × 10−4, respectively, P < 0.025), picomoles per mg protein (0.262 ± 0.0055 vs. 0.0153 ± 0.0054, respectively, P < 0.001), or picomoles per DNA (1.96 ± 0.80 × 10−4 vs. 1.10 ± 0.28 × 10−4, respectively, P < 0.025). These results show that the number of estradiol receptors in the uterus of rats malnourished early in life is decreased. This is more evidence that early malnutrition produces damage in the uterus of the rat.

Insuficiencia suprarrenal primaria por adrenalitis autoimnume

We report a 10 years old boy, admitted with a history of asthenia, anorexia and weight loss of 4 kg. Initial laboratory work up showed metabolic acidosis and hyponatremia. The patient had no circadian rhythm of serum cortisol and an adrenal stimulation test confirmed the presence of adrenal insufficiency. Anti-adrenal antibodies were positive. Treatment with cortisol and fluorocortisone resulted in a complete remission of symptoms.