Thyroid hemiagenesis and elevated thyrotropin levels in a child with Williams syndrome.

A girl with Williams syndrome (WS) presented with elevated thyrotropin (TSH) levels (7.0 microU/ml), normal free thyroid hormone concentrations, and absent antithyroid autoantibodies. Thyroid ultrasonography and scintigraphy showed hemiagenesis of the left lobe and no evidence of ectopic tissue. TSH response to thyrotropin-releasing hormone (TRH) injection (200 microg/mq, i.v.) was exaggerated and prolonged, suggesting subclinical hypothyroidism. The biological activity of circulating TSH was slightly below the normal range [TSH bioactivity (B) to immunoreactivity (I) ratio (TSH B/I) = 0.4, normal: 0.6-2.2]. These abnormalities are similar to those seen in patients with hypothalamic hypothyroidism. Thyroid function is not a recognized manifestation of WS and is not routinely investigated. However, abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis and thyroid dysgenesis have been found in other WS cases. Genes mapping at 7q11.23, contiguous to the chromosomal region deleted in most WS patients, may be involved in the development of the thyroid gland, contributing to the complex phenotype of WS.

Auto-immunity in children with diabetes mellitus and in their relatives.

Islet cell antibodies (ICA-IgG and complement-fixing-ICA), parietal cell antibodies (PCA), intestinal epithelial cell antibodies (IECA), thyroglobulin (TgA) and thyroid microsomal antibodies (MsA), antinuclear (ANA) and reticulin antibodies (RA), were studied in 55 insulin-dependent diabetic patients (30 males and 25 females), aged 2-19 years with diabetes from a few days up to 14 years. In 58% of the diabetics one or more autoantibodies were found: ICA-IgG (31%), CF-ICA (16%), PCA (34%), TgA (9%), MsA (9%), ANA (13%), RA (2%). Autoantibodies were significantly more frequent in females (76%) than in males (43%) (P less than 0.025). ICA-IgG, CF-ICA, PCA, ANA were significantly more frequent in patients than in controls. The frequency of ICA-IgG and CF-ICA was significantly higher during the first 3 years of disease than afterwards (P less than 0.001); a similar pattern was observed for PCA, TgA, MsA. Of the 87 parents and 30 siblings screened for ICA-IgG, CF-ICA, PCA, IECA, TgA, MsA, ANA and RA, 42 (44%) had one or more autoantibodies, which were more frequent in females than in males. Seven relatives (6%) were ICA-IgG positive (four mothers, two fathers and one brother), and only one mother, ICA-IgG negative, was CF-ICA positive. Other autoantibodies were also more frequent in parents than in controls. Autoantibody-positive relatives have been asymptomatic up to now.

The sicca syndrome in thalassaemia major.

A 20 year old man with beta thalassaemia developed symptoms of the sicca syndrome. His serum contained rheumatoid factor and antinuclear antibodies. A biopsy specimen of labial salivary gland showed large accumulations of haemosiderin within the parenchymal cells of the acini. Although in this case the sicca syndrome could not be definitely distinguished from Sjögren's syndrome, the patient's HLA type was not the one usually associated with Sjögren's syndrome. Histological appearances suggested that the causative factor of the sicca syndrome was iron overload owing to an intensive blood transfusion regimen.

Immunoglobulin levels, T-cell markers, mitogen responsiveness and thymic hormone activity in Turner's syndrome.

Immunoglobulin levels (IgG, IgA, IgM), percentage and number of circulating B and T lymphocytes, mitogen responsiveness (PHA and Con A) and activity of thymus-dependent serum factor (SF) were estimated in 29 patients with Turner's syndrome (TS), ranging in age from 2.2/12 to 18.4/12 yr. IgG and IgM were decreased in 14 and 12, respectively, while IgA was very low in 1, and increased in 7. Peripheral blood B and T lymphocytes, in vitro responsiveness to PHA, and Con A, and SF activity were in the normal range. The present immunological study suggests that TS is often associated with low levels of serum IgG and IgM. The possible mechanism of these derangements, whether genetic or hormonal (low estrogen/androgen ratio), is discussed.