Thyroid functions in children with Down's syndrome.

OBJECTIVE: To evaluate thyroid function in children with Down's syndrome, and to ascertain the presence of a relationship between overt thyroid diseases and congenital anomalies. MATERIAL AND METHOD: One hundred and forty Down's syndrome patients, aged from 3 days to 13 years 9 months, were evaluated for karyotype, thyroid functions and the coexistence of congenital anomalies. RESULTS: Trisomy 21 was found in the majority of cases (95.7%). Fifty-six patients (40%) had abnormal thyroid functions: 53 (37.9%) hypothyroidism and 3 (2.1%) hyperthyroidism. Ten patients (7.1%) were diagnosed with overt thyroid disease: congenital hypothyroidism 3.6%, acquired hypothyroidism associated autoimmune thyroiditis 1.4% and hyperthyroidism 2.1%. None of the patients with congenital hypothyroidism had athyreosis or ectopic thyroid gland. Sub-clinical hypothyroidism accounted for 32.9% of all cases; 10.7% showed a spontaneous decrease to normal TSH levels and 13.6% had persistently elevated TSH levels with the median follow-up time of 6 and 12 months, respectively. Congenital heart disease, gastrointestinal anomalies and hematological disease were found in 73.6, 10 and 3.6 percent of patients, respectively. There was no statistical correlation between the coexistence of cardiovascular or gastrointestinal disease in Down's syndrome patients with overt thyroid diseases or sub-clinical hypothyroidism to those having normal thyroid functions. CONCLUSION: Sub-clinical hypothyroidism was the most common thyroid abnormality in children with Down's syndrome. A longitudinal and timely-scheduled evaluation of thyroid function is needed to establish the natural course of this abnormality and the proper management guideline.

Childhood diabetes mellitus: recent advances & future prospects.

Diabetes mellitus (DM) is a metabolic disease characterized by absolute or relative insulin deficiency. Absolute deficiency of insulin most commonly results from an autoimmune destruction of insulin producing cells in the pancreas and in general, the term Type 1 DM (T1DM) is used to denote childhood diabetes associated with autoimmunity and absolute insulin deficiency. The term Type 2 DM (T2DM) is used to denote diabetes resulting from a relative deficiency of insulin when insulin secretion is inadequate to overcome co-existent resistance to insulin action on carbohydrate, protein or fat metabolism; T2DM is most commonly associated with the prototypic insulin resistant state of obesity. In the western hemisphere DM is one of the most prevalent chronic diseases in childhood, whereas the incidence of T1DM in developing countries is significantly less than that in the western hemisphere. Epidemiological studies indicate that there is gradual but steady increase in the incidence of both T1DM and T2DM in both developed and developing countries. This review provides an overview of the major advances in our understanding of the aetiology, pathogenesis, and clinical management of DM in children with the focus being on T1DM. Genetic predisposition, environmental causes, and emerging concepts of the pathogenesis of T1DM such as the accelerator hypothesis are discussed. The goals of treating a child with DM are to achieve normal growth and development with prevention of acute and chronic complications of DM. These goals are achieved by co-ordinated care delivered by a multidisciplinary team focusing on insulin administrations, glucose monitoring, meal planning, and screening for complications. Newer insulin analogues ("designer" insulin) and automated methods of delivery via programmable pumps have revolutionized the care of the child with diabetes. Though T1DM cannot yet be prevented, ongoing trials and strategies aimed at modulating the autoimmune response and the burgeoning science of embryonic stem cell biology, and isolating and propagating islet cell progenitor cells are discussed in this review.

Diencephalic syndrome: a rare and easily overlooked cause of failure to thrive.

BACKGROUND: Diencephalic syndrome (DS) is an uncommon cause of failure to thrive in infants and young children. The major manifestations are emaciation, hyperkinesia, and euphoria. Most patients have a tumor in the hypothalamic-optic chiasma region. CASE REPORT: Two children, aged 14 months and 5 years 9 months, who presented with classic features of DS at an onset of 2 and 3 months respectively, were reported. Neurologic examination was normal, except for papilledema in the second child. Imaging of the brain showed a suprasellar mass, identified as pilocytic astrocytoma in both cases. The first case was lost to follow up. The latter underwent partial resection of the tumor and received radiotherapy postoperatively. He gradually gained in weight and height. CONCLUSION: DS should be a differential diagnosis in any children with emaciation despite adequate caloric intake and an inappropriately euphoric mood. Awareness of this syndrome, careful history taking, general detail as well as neurological examination including fundoscopic examination and appropriated investigations are crucial.

Primary congenital hypothyroidism: clinical characteristics and etiological study.

Forty-eight children with primary congenital hypothyroidism, who attended Chiang Mai University Hospital, during 1977-2000, were reviewed. The female to male ratio was 2:1. The age at diagnosis ranged from 1 month to 12 years 4 months, with 27% of the cases diagnosed within the first three months of life, 37.5% within the first year, and 62.5% after one year of age. Constipation, delayed development and growth, feeding problems, prolonged neonatal jaundice and goiter were more common. Prolonged neonatal jaundice was found in every case diagnosed within the first three months. The other common signs were dry or mottled skin, abdominal distension, macroglossia, short stature, puffy face and umbilical hernia. Kocher-Debré-Semelaigne syndrome comprised 18.7% of cases with a 2:1 female to male ratio, and it was found in various forms of hypothyroidism. Thyroid scintigrams were done in 47 patients. Thyroid dysgenesis was the most common etiology (80.9%), which consisted of 40.4% athyreosis, 4.3% hypoplasia, and 36.2% thyroid ectopy. Thyroid dyshormonogenesis accounted for 18.9%, in which only 4 of 9 presented with goiter. Two-thirds of these patients showed a positive result to the perchlorate discharge test, indicating an organification defect. A 11 patients had elevated serum TSH level greater than 50 mU/L. The serum T4 level below 2 microg/dL was observed in 17 of 19 patients with athyreosis, 11 of 1 7 with thyroid ectopy, and 6 of 9 with thyroid dyshormonogenesis. These findings including retarded bone age were unable to differentiate among different groups of hypothyroidism.