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.

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.

Primary hypomagnesemia in Thai infants: a case report with 7 years follow-up and review of literature.

A female Thai baby born to non-consanguineous parents, presented with primary hypomagnesemia at 10 weeks of age, and suffered recurrent convulsions that responded to magnesium supplementation. She was found to have hypomagnesemia (Mg 0.35-1.02 mEq/L) and a low urinary magnesium excretion of less than 10 mg per day, or urinary Mg/Cr that ranged from 0.005-0.01 mg/mg. Intermittent hypomagnesemia and one episode of hypocalcemia with occasional convulsions developed, due to irregular consumption of oral magnesium sulfate, which had a bitter taste, caused frequent loose stools and black staining of the teeth. Better compliance after switching from magnesium sulfate to magnesium oxide resulted in an increased level of serum magnesium and the gradual disappearance of the black staining of the teeth and frequent loose stools. The patient required an oral elemental magnesium dosage of 15-30 mg/kg/day to maintain the serum magnesium level at between 1.02-1.33 mEq/L and keep her free from convulsions. The follow-up period was 7 years during which the patient showed normal physical growth and a mild degree of mental retardation.

The epidemiology of type 1 diabetes in Thai children.

The incidence of type 1 diabetes in children aged 0-15 years in Thailand was reported to be as low as 0.2/100,000/year in 1984-1985. This survey from 1991 to 1995 by the same investigators using the same questionnaires distributed to hospitals in every province demonstrated increasing numbers. In Bangkok, the capital city, a survey was done by using the capture-recapture method, and found a significant incidence of 1.65/100,000/yr. This number is equal to the incidence in other countries in Asia. This result might be effectively considered as an exact incidence rate during this decade.