ABSTRACT
The P450c17a enzyme has a central role in ovarian hyperandrogenism, which is a characteristic of polycystic ovary syndrome (PCOS). Several studies have suggested a possible role for the CYP17 gene, which codes for the enzyme P450c17a and the -34bp T-C polymorphism in the development of hyperandrogenism. The presence of the cytosine, know as A2 allele, has been associated with hyperandrogenism in patients with PCOS. Objective: To evaluate the frequency and association of the -34bp polymorphism in the CYP17 gene and determine its association with hormonal and metabolic characteristics in women with DM1. Patients and Methods: The CYP17 polymorphism was studied in 72 DM1 and 71 control women by PCR and RFLP analysis. The CYP17 genetic dosage was compared with the antropometrical characteristics and the serum concentrations of testosterone, androstenedione, DHEAS and 17OH progesterone in women with DM1. Results: Genotype A2/A2 was present in 20.8 percent and 7.1 percent of DM1 and controls, respectively (p = 0,034). Allele A2 was present in 40.3 percent and 27.5 percent of DM1 and healthy women, respectively (p = 0,031). No association between CYP17 genotypes and hormonal or metabolic characteristics was observed. Conclusion: This study shows that the frequency of the A2/A2 genotype was higher in women with DM1 than in the control group. However, no association between the presence of the polymorphism and circulating steroid levels or BMI was observed.
Subject(s)
Humans , Female , Adolescent , Adult , Diabetes Mellitus, Type 1/genetics , /genetics , Polymorphism, Genetic , Anthropometry , Gene Frequency , Genetic Markers , Genotype , Hyperandrogenism/genetics , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , /geneticsABSTRACT
Human growth is a complex process regulated by several genes, most of which are unknown. Recently, our knowledge regarding the etiology of genetically determined causes of short stature has greatly increased, so molecular analysis is becoming essential for the diagnosis of growth retardation. The advances in our understanding of the molecular mechanisms involved in the function of the somatotrophic axis have resulted in a dramatic enhancement of our ability to diagnose and treat growth disorders. We hope that in the next few years improved methods for identifying specific abnormalities which cause short stature will expand our ability to diagnose other causes of growth retardation, and reduce the proportion of patients with "idiopathic" short stature.
Subject(s)
Humans , Body Height/genetics , Growth Hormone/genetics , Growth Disorders/diagnosis , Growth Disorders/genetics , Insulin-Like Growth Factor I/physiology , Insulin-Like Growth Factor I/genetics , Pituitary Gland/physiology , Hypothalamus/physiology , Growth Hormone-Releasing Hormone/physiology , Growth Hormone-Releasing Hormone/genetics , Growth Hormone/physiology , MutationABSTRACT
Insulinoma is a very uncommon tumor in children, with an incidence in adults of 2 per million inhabitants. Clinical manifestations include neuroglycopenic or autonomic manifestations due to hypoglycemia. We describe 2 pediatric patients with insulinoma, characterized by repeated episodes of hypoglycemia associated to high insulin serum levels and presence of a small mass in the pancreas by imaging studies. The diagnosis was very prompt in one case and delayed in the other, emphasizing the need for an appropriate diagnosis of hypoglycemia during childhood.
El insulinoma es un tumor muy infrecuente en la edad pediátrica y la incidencia reportada en adultos es de 2 casos por millón de habitantes. La presentación de la enfermedad consiste en la presencia de síntomas neuroglicopénicos y autonómicos desencadenados por los episodios de hipoglicemia. Se describen dos pacientes con insulinoma esporádico. El cuadro clínico consistió en episodios repetidos de hipoglicemia asociados a niveles aumentados de insulina sérica y a imágenes sugerentes de un tumor pancreático. El diagnóstico fue muy oportuno en uno de los casos y muy tardío en el otro, lo que resalta la necesidad de estar muy alerta ante casos de hipoglicemia durante la niñez.
Subject(s)
Humans , Male , Adolescent , Hypoglycemia/etiology , Hypoglycemia/therapy , Insulinoma/complications , Insulinoma/diagnosis , Pancreatic Neoplasms , Clinical Evolution , Glucagon/administration & dosage , Blood Glucose/analysis , Insulin/blood , Signs and SymptomsABSTRACT
Background: The lack of catch up growth (CUG) in small for gestational age (SGA) children may be related to a reduced sensitivity to insulin growth factor 1 (IGF-I). Aim: To assess the sensitivity to IGF-I in small for gestational age children, measuring basal and post IGF-I nocturnal profile of growth hormone (GH). Patients and methods: We studied 34 prepubertal SGA children aged 4 to 11 years. Twenty three had CUG and 11 did not have CUG. As an IGF-I sensitivity test, nocturnal GH levels were measured every 20 minutes from 23:00 h to 07:00 h, both under baseline conditions and after the administration of a subcutaneous bolus of 1 mg/kg/body weight of the IGF-I + IGFBP-3 complex (Somatokine®). Results: At the time of the study, the Z scores for height among children with and without CUG were -1.55 ± 0.22 and -3.24 ± 0.28, respectively (p <0.0001). There were no statistical differences between CUG + vs CUG- patients in mean basal GH (6.6 ± 0.5 and 5.6 ± 0.6 ng/ml, respectively). After Somatokine® administration, mean GH, and the mean GH area under the curve (AUC) decreased significantly in both groups. However, mean overnight GH AUC decreased in all SGA children with CUG, after Somatokine® administration, whereas 3 out of 11 SGA children without CUG had an increase in their mean GH AUC in response to Somatokine®. Conclusions: These findings suggest that pituitary sensitivity to IGF-I may be decreased in some SGA children without CUG.
Subject(s)
Child , Child, Preschool , Female , Humans , Infant, Newborn , Male , Pregnancy , Growth Hormone/blood , Infant, Small for Gestational Age/blood , /blood , Insulin-Like Growth Factor I/analysis , Recombinant Fusion Proteins/administration & dosage , Biomarkers/blood , Body Height , Growth Hormone/metabolism , Immunoradiometric Assay , Infant, Small for Gestational Age/growth & development , /metabolism , Insulin-Like Growth Factor I/metabolismABSTRACT
En la última década se ha demostrado la importancia del control glicémico en la prevención de las complicaciones microvasculares de la DM1. Para lograr este objetivo se ha propiciado el uso de esquemas terapéuticos de insulina intensificados. Objetivo: Comunicar los nuevos esquemas terapéuticos que se utilizan en niños y adolescentes con DM1 y sus resultados en el control metabólico. Método: Se evaluaron los esquemas insulínicos utilizados por todos los pacientes < 19 años en control durante 2003, clasificándolos en tratamiento intensificado (doble o triple dosis de NPH o Glargina) o convencional (< 2 dosis/día). Se consignaron las dosis utilizadas, la HbA1c promedio, el resultado del programa educativo (conocimiento de cantidad de hidratos de carbono, intercambio de alimentos, cambio de dosis según ingesta de hidratos de carbono (HdC) y proporción Insulina/ HdC) y se compararon los resultados obtenidos con las distintas modalidades de tratamiento. Resultados: Se estudiaron 69 pacientes con DM1 (36 mujeres), de 12,0 ± 3,7 años (2-19 años), 59,7% púberes. Todos utilizaban una insulina basal (69,2% de la dosis diaria) y otra prandial; 87% de los pacientes requirieron tres o más dosis diarias de insulina y 13% utilizaba esquema convencional de dos dosis de NPH. Los pacientes en tratamiento intensificado recibían tres o cuatro dosis diarias de insulina prandial, con los siguientes esquemas de insulina basal: dos dosis diarias de NPH (28%), glargina (10%) y tres dosis diarias de NPH (49%). 88,4% de los pacientes modificaba la dosis de insulina rápida según la glicemia y 46,4% consideraba la ingesta de HC; 27% conocía la relación HdC/insulina y 79,7% se colocaba refuerzos adicionales de insulina al comer fuera de sus horarios. La HbA1C del grupo fue de 8,6 ± 1,4%; 30,4% de los pacientes logró el objetivo de HbA1c establecido en el programa, sin diferencias respecto al esquema de insulinoterapia basal utilizado. Por análisis de ...
Introduction: During the last decade the importance of glycaemic control in the prevention of microvascular complications of type 1 diabetes mellitus (DM1) has been demostrated. To achieve this goal, different modalities of intensive therapy have been recommended. Objective: To communicate a novel therapeutic modality employed in paedriatric patients and the metabolic control achieved. Methods: All DM patients < 19 years were included. Insulin treatment was consigned and classified as intensive (at least 3 daily doses, 2 or 3 NPH daily doses, or glargin) or conventional (2 or less doses). Number of doses, mean HbA1c during 2003, results of educative programmes were evaluated and compared. Results: 69 patients (36 females) were studied, 59,7% were pubertal, with a mean age of 12,0 ± 3,7 years. All patients used a basal insulin (69,2% daily dose) and a prandial insulin. Intensive therapy was used by 87% of children. Patients with multiple daily doses received 3 or 4 inyections of a short or rapid acting insulin. Basal insulin was glargine in 10%, twice daily NPH in 28% and thrice daily in 49%. Patients modified dose according to glucose level occured in 88,4%, and 46,4% considered carbohydrate intake. 27% knew the carbohydrate/insulin ratio and 79,7% used additional insulin when eating extra carbohydrates. The BbA1c was 8,6 ± 1,4% without differences in terms of insulin modality used. 30,4% achieved the proposed goals of HbA1c. The total and basal insulin usage correlated with the HbA1c. Conclusions: Multiple modalities of insulin therapy are available, no difference in metabolic control between the modalities was detected. We have achieved very good control in 30% of the patients, only insulin daily dose and basal dose correlated significatively with HbA1c.
ABSTRACT
El hiperinsulinismo neonatal constituye la causa más común de hipoglicemia persistente en el menor de 1 año. Existe una secreción inapropiada de insulina en condiciones de hipoglicemia debido a una alteración en el receptor de sulfonilurea en la célula beta pancreática. Se describe el caso de un recién nacido prematuro, pequeño para la edad gestacional, que presentó precozmente hipoglicemias de difícil manejo, requiriendo cargas de glucosa de hasta 26 mg/kg/min. Tras confirmar el diagnóstico se inició tratamiento médico con octreotide. Luego de 72 horas de iniciado el tratamiento se logró disminuir el aporte de glucosa endovenosa, suspendiéndolo a las 6 semanas. En el seguimiento no se han presentado complicaciones derivadas del tratamiento, su situación nutricional es adecuada y su desarrollo psicomotor es normal. El uso de octreotide debe ser considerado como alternativa terapéutica en niños con hiperinsulinismo persistente, evitando la cirugía que presenta alta morbimortalidad, especialmente en este grupo etario.
Subject(s)
Humans , Infant , Blood Glucose , Hyperinsulinism/complications , Hyperinsulinism/diagnosis , Hyperinsulinism/drug therapy , Congenital Hyperinsulinism , Octreotide/administration & dosage , Octreotide/therapeutic useABSTRACT
Background: Recent studies in the United States have demonstrated that a significant proportion of girls show thelarche before the age of eight years. Nutritional status, geographic influences and racial factors are known to affect the timing of puberty. Aim: To evaluate the age of onset of puberty, development of secondary sexual characteristics and menarche in Chilean girls, and its relation to obesity and socioeconomic status. Material and methods: Healthy girls attending elementary school, from first to ninth grade in Santiago, Chile, were studied. A pediatric endocrinologist evaluated pubertal development using Tanner classification. Breast development was assessed by inspection and breast palpation. Average age of onset of pubertal events was determined by probit analysis. Results: A total of 758 girls, aged 5.8 to 16.1 years, were recruited. Obesity, defined as a BMI greater than 90th percentile, was found in 24.4 percent. The age of menarche was 12.7 years, the onset of Tanner stage 2 breast development and pubic hair was at 8.9 and 10.4 years, respectively. Sixteen percent of girls aged 7 to 7,9 years, had thelarche. Upper class girls showed a later onset of breast Tanner stage 4 stage than low-middle class girls. Obesity was not found in logistic regression analysis to be a significant predictive factor in the onset of puberty. Conclusions: The age of menarche has not changed in the last thirty years, but an earlier onset of thelarche has occurred. The high frequency of thelarche between 7 and 8 years suggests that the normal age of breast development should be revised.
Subject(s)
Humans , Female , Child , Adolescent , Socioeconomic Factors , Puberty/physiology , Chile/epidemiology , Social Class , Sexual Maturation/physiology , MenarcheABSTRACT
Background: Short stature is the main feature of patients with Turner's syndrome. There is limited information regarding the spontaneous growth of these patients in Chile. Aim: To develop a specific growth chart for Chilean patients with Turner's syndrome. Material and methods: We retrospectively analyzed 668 height measurements from 85 Chilean girls, born after 1968, with 45XO karyotype (minimum 15 percent), and without an Y chromosome fragment. Patients with hormonal therapy, such as growth hormone or estrogen, except thyroid hormone replacement, were excluded. Results: The karyotypes were 60 percent 45XO, 25 percent 45XO, 46XX, and 15 percent other complex mosaics. The birth length was 46.8 ñ 2.1 cm. The final height of our patients was 138,20 ñ 7,0 cm. Conclusions: The final height achieved by our patients, is similar to Argentinian and Japanese patients, but is below the mean stature reported for Scandinavian and Northamerican patients who achieve a mean adult height of approximately 147 and 142 cm respectively. The birth length is also lower than that reported in those studies
Subject(s)
Humans , Adolescent , Female , Infant , Child, Preschool , Growth Disorders , Turner Syndrome/physiopathology , Turner Syndrome/complications , Turner Syndrome/ethnologyABSTRACT
Introducción: Existe evidencia en la literatura norteamericana que la edad de inicio de la pubertad en las niñas se estaría adelantando. No existen trabajos que prmitan establecer este hecho en nuestra población. Objetivo: Evaluar la edad de inicio de desarrollo puberal en niños y niñas que asisten a 3 colegios del cector céntrico de Santiago. Sujetos y métodos: Se reclutaron 332 niños , se determinó peso, talla e IMC (peso/talla) y se descartaron los 80 (24 por ciento) con IMC < p10 o > p95, ingresando 252 escolares (131 niñas). Se realizó examen físico y se consideró como inicio de desarrollo puberal la aparición del tejido mamario en las niñas y un volumen testicular de 4 cc o mayor en los varones. Resultados: En el intervalo de edad de7 a 7.49 años habían 2/20 (10 por ciento) niñas con boton mamario, en el de 7.5 a 7.99 4/16 (25 por ciento) y en el de 8 a 8.99 años 9/36 (25 por ciento). En el varón, el primer signo de activación del eje pituitario gonadal aparecio en el grupo de 9 a 9.49 años, similar a lo descrito previamente. Conclusión: La edad de inicio del desarrollo puberal en este grupo de niñas chilenas, se estaría adelantando en relación a la litaratura clásica, mientras que en el varó no se demuestran cambios. Estos resultados sugieren que el inicio del desarrollo mamario en las niñas entre los 7 y 8 años, no debería considerarse siempre como patológico y que habría que reevaluar la definició de pubertad precoz
Subject(s)
Humans , Male , Female , Puberty , Puberty, Precocious , Body Mass Index , Breast , Child Development , Chile , Testis/growth & development , Weight by HeightABSTRACT
Background: McCune-Albright Syndrome (MAS) is characterized by precocious puberty, "cafe au lait" skin lesions and polyostotic fibrous dysplasia. It is caused by 4 post-zygotic mutations of Gas protein with a mosaic distribution. Aim: To describe the clinical presentation and to investigate the presence of the Arg by his substitution (R201H) in 14 girls with MAS. Patients and methods: We performed a clinical analysis of the patients and specific allele PCR in DNA obtained from leukocytes. Results: Twelve of 14 patients presented with precocious puberty, one with cyclical vaginal bleeding and one with pathological bone fractures. Eight girls had polyostotic fibrous dysplasia, one had hyperthyroidism, four had pathological fractures, ten had ovarian cysts, six had breast hyperpigmentation and ten had "cafe au lait" skin lesions. We detected the R2O1H mutation in 10 of 14 patients. We found no difference in the severity of symptoms or in the age of presentation between the patients with and without the mutation. Conclusions: The R201H mutation can be detected in white blood cells, in approximately 70 per cent of cases. Patients exhibit wide clinical variability with the same molecular defect. This suggests that tissues have different proportions of mutant cells
Subject(s)
Humans , Female , Infant, Newborn , Infant , Child, Preschool , Fibrous Dysplasia, Polyostotic/genetics , Puberty, Precocious , Case-Control Studies , Polymerase Chain Reaction , Gene Amplification/methodsABSTRACT
Circulating concentrations of the high affinity growth hormone binding protein (GHBP) may be a marker of GH receptor density as well as GH sensiffvity. Goal: To determine values of GHBP for a normal Chilean pediatric population. Methods : We determined GHBP levels in 73 males and 73 females between 4 to 15.5 years and 4 to 16.8 years respectively, divided in 7 groups according to age and puberal status. Results: The population was normally distributed in weight, height and body mass index (BMI). GHBP activity increased up to Tanner IV in males and Tanner III in females, and decreased slightly thereafter in Tanner V and IV respectively. There was a significant difference between GHBP levels of preschool children and those found in Tanner II to V in both sexes (p<0.05). In adition, we found a positive correlation between GHBP vs weight, height and BMI (p<0.001) in males and females. Conclusion : The availability of this methodology allows us to establish the normative value of GHBP in our population and provides useful information to interpret GH circulating levels in children with growth disorders
Subject(s)
Humans , Male , Female , Child, Preschool , Adolescent , Growth Hormone/blood , Carrier Proteins/blood , Reference Values , Growth/physiology , Body Mass IndexABSTRACT
Recently, several groups have studied the influence of possible noxious elements present in the intrauterine environment which may favor the development of several diseases in the adult. There is evidence of an increased prevalence of some disorders in special risk groups of fetuses. In the small for gestational age patient, a form of "programming" may occur which produce metabolic changes in the fetus in response to malnutrition. There are several other associations described, but in most of them the precise pathogenic mechanisms involved have not been elucidated. In this article we present evidence of several disorders which develop in the adult and their relationship with conditions during fetal life. Finally, we offer some recommendations to diminish these risks
Subject(s)
Humans , Male , Female , Risk Groups , Morbidity/trends , Prenatal Exposure Delayed Effects , Respiratory Tract Diseases/etiology , Cardiovascular Diseases/etiology , Growth Disorders/etiology , Nervous System Diseases/etiology , Metabolic Diseases/etiologyABSTRACT
Background: The diagnosis of GH deficiency (GHD) is based upon the results of GH stimulation tests, which have several drawbacks. Aim: To evaluate the usefulness of IGF-1 and IGFBP-3 for the diagnosis of GHD in prepuberal children. Material and methods: We measured IGF-I and IGFBP-3 in three group of subjects: I. GHD (n:24), height <-2SD for age (Z score, average ñ SD: -4.2 ñ 1.2), growth velocity
Subject(s)
Humans , Male , Female , Insulin-Like Growth Factor I , Insulin-Like Growth Factor Binding Protein 3 , Human Growth Hormone/deficiency , Weight by Height , Radioimmunoassay , Case-Control Studies , Clonidine/pharmacology , Growth Disorders/diagnosis , Growth Disorders/etiology , Body Mass IndexABSTRACT
En una niña con hipotiroidismo primario debido a tiroides sublingual y talla baja desde los dos años de edad, la resonancia magnética mostró aumento del tamaño de la hipófisis sugerente de macroadenoma, que después de una prueba terapéutica con hormona tiroidea recuperó el aspecto normal. El hipotiroidismo primario crónico puede producir aumento de volumen hipofisiario indistinguible del causado por un macroadenoma en los exámenes por imágenes. El tratamiento con hormona tiroidea permite el diagnóstico diferencial entre ambas entidades
Subject(s)
Humans , Female , Child, Preschool , Adenoma/diagnosis , Hypothyroidism/complications , Pituitary Neoplasms/diagnosis , Hyperplasia/diagnosis , Hypothyroidism/diagnosis , Hypothyroidism/drug therapy , Magnetic Resonance Spectroscopy , Thyroxine/therapeutic useABSTRACT
Niño de 6 años derivado por tallo bajo con micrognatia, paladar ojival, cuello alado, aréolas pequeñas y bajas, cúbito valgo, acortamiento del cuarto metacorpiano y escoliosis, que sugerían síndrome de Turner. En su cariotipo se identificó un isocromosoma del brazo largo del cromosoma Y: 46, X, i (Y) (qIO). En la ultrasonografía el útero tenía aspecto prepuberal y los ovarios no se identificaron. Se exploró mediante cirugía extirpando ambas gónadas, debido al riesgo de desarrollar un tumor gonadal dado la presencia de un cromosoma Y. En el examen histopatológico se encontraron esbozos de trompas y características de gonadoblastoma
Subject(s)
Humans , Female , Gonadoblastoma/diagnosis , Ovarian Neoplasms , Gonadoblastoma/etiology , Gonadoblastoma/surgery , Isochromosomes , Ovariectomy , Turner Syndrome/diagnosis , UterusABSTRACT
La consulta por retraso del crecimiento es muy frecuente en pediatría. En la última década se han efectuado importantes avances en la comprensión de los mecanismos hormonales que regulan el crecimiento infantil. Este artículo tiene por objeto hacer una actualización sobre el sistema hormona de crecimiento (GH) -efector. Se revisan los mecanismos de control hipotalámico de la secreción de GH (factor liberador de GH y somatotastina), secreción hipofisiaria de GH, la proteína ligadora de GH (GHBP), el receptor de GH y sus efectores periféricos (IGFs e IGFBPS). Se analizan las repercusiones clínicas de las alteraciones de cada uno de estos componentes, que pueden conducir a una falla en el crecimiento durante la infancia
Subject(s)
Humans , Child , Failure to Thrive/diagnosis , Human Growth Hormone/metabolism , Growth Hormone-Releasing Hormone/metabolism , Human Growth Hormone/deficiency , Receptors, Somatotropin , Hypothalamo-Hypophyseal System , Somatomedins/metabolism , Somatostatin/metabolismABSTRACT
Se describe una adolescente que sufría de hipertiroidismo severo de larga evolución, con pobre respuesta a medicamentos antitiroideos y dos episodios de ictericia previos, que ingresó con un hipertiroidismo clínicamente activo a pesar de estar recibiendo propiltiouracilo, ictericia intensa y hepatomegalia. El estudio y manejo de su hepatitis fue complejo, dado que las posibilidades de disfunción hepática en el contexto de un hipertiroidismo, podrían obedecer a toxicidad por drogas, insuficiencia cardíaca, hipertiroidismo por sí mismo o hepatitis autoinmune. Se manejó con suspensión del propiltiouracilo, régimen hipercalórico, propanolol y dos dosis de I131, con lo cual se logró controlar el hipertiroidismo. El estudio de laboratorio e histopatológico fue compatible con hepatitis crónica activa que se manejó con corticoides orales, coincidiendo con lo cual la paciente está asintomática, si bien la biopsia hepática muestra aún signos de actividad
Subject(s)
Humans , Female , Adolescent , Graves Disease/complications , Hepatitis, Chronic/complications , Hyperthyroidism/complications , Propylthiouracil/adverse effects , Adrenal Cortex Hormones/administration & dosage , Hepatitis, Chronic/drug therapy , Hyperthyroidism/drug therapyABSTRACT
Se describe un niño afectado por gigantismo hipofisiario. Las manifestaciones clínicas de su enfermedad comenzaron a los 8 años de edad, con aceleración del crecimiento, cefalea y un año después, amaurosis derecha que motivó su ingreso al hospital. Su talla era >p95 para edad, facies tosca, manos pies grandes, amaurosis derecha y cuadrantopsia izquierda. La concentración sérica de hormona de crecimiento era anormalmente alta y no supresible con sobrecarga oral de glucosa, la somatomedina C estaba aumentada y sufría déficit de hormonas tiroídea y cortisol. En la tomografía axial computadorizada se registró un tumor hipofisiario con extensión supraselar. Los padres rechazaron cualquier tratamiento. Reingresó un año después por hipertensión endocraneana, amaurosis bilateral y aumento del tamaño del tumor en la resonancia nuclear magnética. Se realizó resección trasesfenoidal del tumor hipofisiario, cuya histología correspondía a macroadenoma con necrosis y hemorragia y calcificaciones. Su evolución postoperatoria fue satisfactoria, manteniéndose en tratamiento de sustitución con hormona tiroidea y suprarrenal. Un año después de operado el niño está asintomático, las concentraciones séricas de hormona de crecimiento y somatomedina C son normales y no hay signos radiológicos de recidiva del tumor
Subject(s)
Humans , Male , Child , Gigantism/pathology , Pituitary Neoplasms/complications , Blindness/etiology , Growth Hormone/blood , Hydrocortisone/administration & dosage , Hydrocortisone/blood , Hypothyroidism/complications , Insulin-Like Growth Factor I , Prolactin/blood , Thyroid Hormones/blood , Thyroxine/administration & dosageABSTRACT
El retraso de crecimiento de un niño por alteraciones en la hormona de crecimiento puede producirse por déficit en su producción o por falta de respuesta a su efecto. Ambos grupos de niños tienen características clínicas bastante similares. La hormona de crecimiento ejerce su efecto biológico a través de receptores tisulares, y si éstos están alterados se producirá un cuadro de resistencia periférica a dicha hormona. Presentamos un niño que consultó a los 14 años y 7 meses de edad por retraso severo del crecimiento, con talla de 95 cm, obesidad centrípeta, manos y pies pequeños, micropene y facies infantil, características sugerentes de un déficit de hormona de crecimiento. El estudio de laboratorio mostró concentraciones plasmáticas elevadas de hormona de crecimiento elevados y disminución de las de somatomedina-C. El paciente fue tratado con hormona de crecimiento biosintética, sin respuesta bioquímica ni clínica, lo que sugiere resistencia periférica a la acción de la somatotropina