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McCune-Albright syndrome (MAS) is a sporadic disease characterized by fibrous bone dysplasia, café-au-lait spots and hyperfunctional endocrinopathies. We report a 2.5-year-old child with MAS with an early and nonclassic onset. He was admitted to our attention for frequent fractures without clinical signs of endocrinopathies, found to have asymptomatic, nonautoimmune hyperthyroidism. The diagnosis of MAS was based on RX and MR imaging associated with hyperthyroidism. It is not clear if there was a correlation between the severity of bone disease and the presence of thyroid disorder. At the moment no standard treatment exists for bone fibrous dysplasia and hyperthyroidism in children before the age of 6 years., (Copyright 2002 S. Karger AG, Basel)

Urinary growth hormone (uGH) excretion was evaluated in 96 type-1 insulin-dependent diabetic patients and 37 age-matched healthy subjects. The growth hormone concentration was measured by a solid-phase immunoradiometric assay on 3 consecutive overnight urine collections. uGH excretion was comparable between diabetic patients and healthy subjects: 10.9 (0.1-34.8) vs. 9.1 (2.6-34.5) pg/min. In both groups uGH excretion was lower in prepubertal than in pubescent or pubertal individuals (diabetic patients, H = 29.7, p = 0.001; healthy subjects, H = 10.4, p = 0.006). In diabetic patients uGH excretion was related to beta 2-microglobulin excretion (r = 0.308; p = 0.005) and to urinary albumin excretion (r = 0.230; p = 0.02) but it was independent of HbA1c and overnight glycemic values. The coefficient of variation of uGH excretion was higher in diabetic patients with respect to healthy subjects: 50 (3-141) vs. 28(3-100)% (p = 0.002). Among diabetic patients it was greater in prepubertal than in pubescent or pubertal patients (H = 13.7; p = 0.002); in contrast, it was independent of pubertal stage in healthy individuals (H = 2.4; NS). The coefficient of variation of uGH was not related to HbA1c, the duration of diabetes, the coefficient of variation of urinary albumin excretion and the coefficient of variation of beta 2-microglobulin excretion. In conclusion uGH excretion is comparable among diabetic patients and healthy subjects, but its day-to-day fluctuation is greater in the former than in the latter group. Renal function but not metabolic control can influence uGH excretion. The day-to-day fluctuation in uGH excretion is independent of metabolic control and renal function.

Improvement of MRI diagnostic accuracy in the study of the hypothalamic-pituitary region provides precise anatomic details. In pituitary dwarfism, MRI reveals severe sella/pituitary gland and stalk hypoplasia with or without posterior pituitary ectopia, and empty sella, and this more frequently in patients with multiple pituitary hormone deficiency. Two main hypotheses have been proposed to explain these findings: traumatic stalk transection during breech delivery, and abnormal embryonic development of the pituitary gland. The association between neuroradiological findings and type/severity of endocrine alteration has not yet been clarified. In diabetes insipidus, MRI findings are normal picture, posterior lobe not visible, and thickened stalk (as expression of preclinical/initial histocytosis). Patients with central precocious puberty or hypogonadotropic hypogonadism rarely show morphologic abnormalities (hamartoma of the tuber cinereum, partially empty sella). So far, MRI permits one to identify morphologic pictures in diseases previously considered 'idiopathic'.

Prolactin response after domperidone (DOM) stimulus was used to investigate the functional status of the hypothalamo-hypophyseal axis in 57 congenital growth-hormone-deficient (GHD) children with and without magnetic resonance imaging (MRI) abnormalities. Response to DOM was significantly lower in the GHD children compared with controls, using maximum peak (p < 0.0001), increase (p < 0.0001) or percentage increase (p < 0.05). The lowest values were observed in patients with hypophyseal stalk transection. Thus, the DOM test revealed reduced dopaminergic transmission in GHD subjects, more severe in the transected group, in whom, however, a response to the stimulus was still present. Therefore, it seems that a residual hypothalamo-hypophyseal connection is preserved even if it is not detectable with MRI.

A group of infants, affected by congenital hypothyroidism diagnosed through the neonatal screening program, was investigated with echocardiography to detect the presence of pericardial effusion. We studied the relationship between the effusion and the etiology of hypothyroidism, established through thyroid scintiscanning. Our data show a high prevalence of effusion in hypothyroid patients, without other clinical signs of cardiac involvement as well as a relationship between the etiology of hypothyroidism and the presence of effusion. This seems to be much more frequent in those forms which can imply a more severe hormonal defect, particularly during fetal life (agenesis/dyshormonogenesis). Furthermore, the high prevalence of pericardial effusion suggests to start the L-T4 replacement therapy with lower dosages as commonly advised, in order to avoid a cardiac involvement.

Fifty-seven children with growth hormone deficiency and 15 healthy age-matched controls were studied by magnetic resonance imaging (MRI). Of the patients, 36 (63%) had isolated GH deficiency (IGHD) and 21 (37%) multiple pituitary hormone deficiency (MPHD). MRI studies showed a marked reduction in pituitary volume in all patients in comparison with normal controls. Moreover, a striking morphological abnormality with the apparent absence of the pituitary stalk and an ectopic posterior pituitary lobe was detected in 34 of the patients (59%). This pituitary stalk abnormality was detected in 95% of the MPHD patients and in 39% of the IGHD patients. All but one of the patients with a normal pituitary stalk had IGHD. Endocrine evaluation showed no correlation with MRI data: in particular patients with an apparent anatomical interruption of the hypothalamic-pituitary axis showed a variety of patterns of hormonal responses. In conclusion, our study shows a high frequency of hypothalamic-pituitary anomalies in patients with GH deficiency, particularly related with MPHD. However, further studies are needed to improve our understanding of the relationship between MRI and endocrine data.

The effect of arginine infusion on blood glucose and plasma levels of insulin, C-peptide and glucagon has been studied in leukemic children before and after treatment with L-asparaginase (10,000 U/m2/day for 10 days). Therapy induced a significant reduction in basal and peak blood glucose, insulin and C-peptide levels, while glucagon was unmodified. The conserved C-peptide-insulin molar ratio suggests the interference of L-asparaginase with proinsulin synthesis. In conclusion our results prove a decreased insulin reserve with a preserved, although reduced, beta-cell function.

15 insulin-dependent diabetic children at onset were randomly allocated to one of two different therapeutical protocols: continuous subcutaneous insulin infusion (CSII) and intensified conventional insulin treatment with three daily insulin injections (CIT). Both treatments were performed for 10 days; the initial insulin dose was 1.5 U/kg/day and thereafter the insulin dosage was modified in order to obtain a satisfactory control. Near-normal blood glucose levels were obtained after 24 h in the CSII group, and after 3 days in the CIT group. All subjects underwent 1 year of follow-up. HbA1 levels and insulin requirements decreased similarly in the two groups; C-peptide secretion did not increase significantly in both groups. A clear advantage of CSII cannot be assumed, and the usefulness of this therapeutical approach needs to be confirmed by further investigations.