Lower bone mineral content in children with type 1 diabetes mellitus is linked to female sex, low insulin-like growth factor type I levels, and high insulin requirement.

CONTEXT: Studies on bone mineral characteristics in children with type 1 diabetes mellitus (T1DM) have generated conflicting results. OBJECTIVE: Our objective was to investigate bone mineral characteristics in children with T1DM and to analyze their associations with bone metabolism and the IGF-I system. DESIGN: We recruited a cohort of Caucasian patients with T1DM for at least 3 yr and healthy children between January 2003 and June 2004. SETTING: This was a university hospital-based study. PARTICIPANTS: A total of 127 patients and 319 controls aged 6 to 20 yr participated. METHODS: Dual-energy x-ray absorptiometry was performed in patients and controls. Serum bone alkaline phosphatase, CrossLaps, IGF-I, and IGF-binding protein 3 levels were determined in patients with values analyzed using our normative data from 1150 healthy children. RESULTS: After adjustment for age, sex, pubertal stage, and body mass index sd score, total body bone mineral content (BMC)/lean body mass was significantly lower in patients than in controls (P < 0.04). This difference was a result of the differences between the girls of the two groups. Girls with T1DM had significantly lower lumbar spine and total body BMC than control girls (P = 0.002), whereas no such difference was observed in boys. Serum bone alkaline phosphatase level was significantly lower in girls than in boys (P = 0.04). Low serum IGF-I levels and the administration of large amounts of insulin were found to have independent deleterious effects on BMC for children of all ages and both sexes, whereas disease duration and glycosylated hemoglobin levels did not. CONCLUSIONS: A sex-related difference in the impairment of bone mineral characteristics was identified in children with T1DM. Longitudinal studies are required to investigate whether boys may gain slightly less bone mass during skeletal growth.

Epidemiology of thyroid dysgenesis: the familial component.

The pathophysiology of thyroid dysgenesis remains unclear and, until recently, this disorder was generally regarded as sporadic. However, a small but significant proportion of familial cases have been identified (2%) through the study of subjects with congenital hypothyroidism, and more recent work has revealed an even higher proportion of familial thyroid dysgenesis in both symptomatic and asymptomatic individuals. These studies strongly suggest the existence of a familial component of this disorder involving dominant genetic predisposition factors with a low penetrance.

Improvement in bone mineral density and body composition in survivors of childhood acute lymphoblastic leukemia: a 1-year prospective study.

OBJECTIVES: Abnormalities in bone mineral density (BMD), body composition, and bone metabolism have been reported in children who were treated for acute lymphoblastic leukemia (ALL) during and after completion of therapy. However, these studies are cross-sectional, and no longitudinal data are available in a large group of patients after completion of therapy. In the present study, 1-year longitudinal changes in BMD, body composition, and bone metabolism were evaluated in children with ALL during the first 3 years after completion of therapy without cranial irradiation. METHODS: BMD of total body (TB; g/cm(2)), areal and apparent volumetric lumbar spine (L2-L4), lean body mass, and percentage of body fat were measured by dual-energy x-ray absorptiometry in 37 children (median age: 7.9 years; range: 4.7-20.6 years) who were treated for ALL at a median age of 3.3 years (range: 1.1-16.6 years), after a median time of 2.2 years after the completion of treatment, and after a 1-year follow-up period. Two control subjects (n = 74) who were matched for gender, age, and pubertal stage were also longitudinally investigated for body composition for 1 year. Usual serum biochemical markers of calcium metabolism and bone turnover were measured in patients during the study period. RESULTS: A slight decrease in TB BMD was found after a median time of 2.2 years after the completion of therapy for ALL in childhood. Patients showed a significantly lower median TB BMD when evaluated <1.5 years as compared with those at >or=1.5 years since completion of therapy. At the time of first evaluation, the percentage of body fat mass was significantly higher and patients were physically less active than their matched control subjects. Although, as expected, during the 1 year of follow-up both groups showed an annual increment in their BMD measurements, a significantly higher increase in TB BMD was observed in patients in comparison with control subjects. During this same period, the increase in the percentage of body fat mass was slightly lower in ALL patients as compared with control subjects. At the end of the follow-up year, BMD, body-composition parameters, and physical activity of ALL patients were similar to those observed in matched control subjects. Serum biochemical markers of bone turnover were normal at both evaluations. CONCLUSIONS: A significant increase in TB BMD and a tendency to a lesser increase in percentage of body fat mass were observed during the study period in ALL patients as compared with chronological age-, gender-, and pubertal stage-matched control subjects. These findings suggest a positive effect of long-term completion therapy and increase in physical activity on BMD, body composition, and bone metabolism in patients who have been treated for ALL.

Ultrasonographic assessment of the ectopic thyroid tissue in children with congenital hypothyroidism.

BACKGROUND: Ectopic thyroid tissue as a result of thyroid developmental abnormalities is the most frequent cause of congenital hypothyroidism (CH). It is diagnosed by using radionuclide thyroid scanning. OBJECTIVE. To evaluate the sensitivity of US in the detection of such ectopias and to describe their US pattern before and during treatment. MATERIALS AND METHODS: Forty-two neonates (group A; aged 11.3+/-4.0 days) and 33 older children (group B; aged 11.1+/-3.9 years) with a biochemical diagnosis of CH and thyroid ectopia detected by radionuclide scanning were evaluated before (group A) and after (group B) treatment. Thyroid US included a survey of the pathway of the thyroglossal tract and an evaluation of the location, size, echogenicity and vascularity of any tissue along this pathway suggestive of thyroid ectopia. RESULTS: Thyroid ectopia was detected using US in 18 patients (24%) with a similar rate during the neonatal period and thereafter on therapy. Three patients demonstrated double ectopia. These 21 sites of ectopic thyroid tissue were located at the suprahyoid level (n=12), at the level of the hyoid (n=1), and at the infrahyoid level (n=8). The maximum diameter of the ectopic tissue ranged from 4 to 14 mm. In group A (9 patients), the 11 ectopias were all hypervascular. These were hyperechoic in all but one neonate. In group B (9 patients), the ten ectopias were not vascular, and were hyper (n=3) or hypoechoic (n=7). CONCLUSIONS: US allows for detection of ectopic thyroid tissue, but with a lower detection rate than radionuclide scanning. However, it does provide a more detailed description of such ectopias.

Efectos nocivos del uso de enalapril sobre la gestación experimental y sus implicancias sobre el uso clínico / Noxious effect of enalapril in experimental pregnancy and clinical implications

Se investigó el efecto del enalapril en la gestación en ratas. A un grupo de 11 ratas se les administró 15 mg/kg/día desde el día primeroal noveno de gestación (E10-20); 12 ratas sirvieron de control (C); 15 animales fueron sacrificados al día 20 y 19 continuaron hasta el parto. Las placentas fueron 15% menores en el grupo E10-20 (p<0.05) y tenían una estructura cordonal hipocelular simple. En el grupo E1-9 el tipo estructural predominante fue una combinación de estructuras simple y compleja. En el día 20 de gestación los fetos de los grupos tratados eran de menor tamaño que los controles (-5% en E1-9 y -16% en E10-20, p<0.05). Las diferencias desaparecieron a los 13 días postparto. En dos fetos tratados se observó calcificación incompleta del cráneo. Estimamos que estos resultados, analizados en el contexto de los daños observados en el embarazo humano, agregan información que fundamenta la abstención del uso de inhibidores de enzima convertidora en el embarazo