Serum leptin levels in girls with precocious puberty.

Few data are available regarding leptin levels in children with different pubertal stages or with precocious puberty (PP). The aim of this study was to assess the changes in serum leptin levels in patients with PP. We studied 20 girls with PP, with Tanner stage II-III; the age at the beginning of pubertal signs ranged from 4.2 to 7.1 yr; all the girls had an advantaged bone age. Controls were subdivided in two groups: group 1: 20 pre-pubertal girls with the same chronological age of the patients, without any signs of pubertal development (Tanner stage I); group 2: 20 additional girls with the same bone age, pubertal stage and body mass index (BMI) of the girls with PP. Serum leptin levels in females with PP are similar to those found in subjects with normal puberty (9.0 +/- 0.8 vs 9.1 +/- 0.9 ng/ml; ns) and different from subjects with the same chronological age without activation of puberty (5.6 +/- 0.9 ng/ml, p < 0.001). In all groups leptin levels correlated significantly with BMI (girls with PP: r = 0.5 1, p < 0.02; control group 1 girls: r = 0.71; p < 0.0001; control group 2 girls: r = 0.49; p < 0.02), there was no significant relationship between leptin and activation of hypothalamic-pituitary-gonadal axis. Our results indicate that the serum leptin levels in the girls with PP are not significantly different from levels in healthy girls at a similar stage of pubertal development, suggesting that the relationship between serum leptin levels and BMI is also present in this pathological situation.

Photoparoxysmal responses in non-epileptic children in long-term follow-up.

OBJECTIVES: To evaluate the photoparoxysmal responses (PPR) in non-epileptic children and adolescents in long-term follow-up. MATERIALS AND METHODS: We studied 14 non-epileptic children who showed PPR without any other electroencephalographic (EEG) abnormalities. RESULTS: One subjects was lost after 1 year of follow-up. At the final follow-up, four of the 13 patients (approximately 30%) did not show any PPR or other epileptic discharges, while in other children PPR continued to be present. The age of the disappearance of PPR in these four patients ranged from 1.1 to 5.9 years from the first evaluation. No patients suffered from epileptic seizures during the whole period of follow-up. CONCLUSION: Our study confirms that PPR can be present in the EEG of non-epileptic children and adolescents and demonstrates that this EEG change is not related to the presence of seizures and must not be considered a marker for the developing of epilepsy.

Serum copper, zinc, selenium, glutathione peroxidase and superoxide dismutase levels in epileptic children before and after 1 year of sodium valproate and carbamazepine therapy.

To assess whether epileptic children have abnormal values of serum copper (Cu), zinc (Zn), selenium (Se), glutathione peroxidase (GSH-PX) and superoxide dismutase (CuZn-SOD), and to evaluate the effect of long-term therapy with sodium valproate (VPA) and carbamazepine (CBZ) on these parameters, we studied 36 epileptic patients before the beginning of therapy and after 1 year of therapy with VPA or CBZ. Before the beginning of therapy, there were no differences in levels of all parameters studied between controls and epileptics. After 1 year of therapy, patients treated with VPA and CBZ continued to show normal values. In conclusion our study demonstrates that epilepsy per se and treatment with VPA and CBZ do not affect levels of Cu, Zn, Se, GSH-PX and CuZn-SOD concentrations.

Thyroid hormones in epileptic children receiving carbamazepine and valproic acid.

Carbamazepine and valproic acid are effective antiepileptic drugs for treating many types of epilepsy. Although they are well tolerated, many effects on endocrine function have been reported. Changes in serum thyroid hormones levels in 37 children with epilepsy during carbamazepine and valproic acid therapy were analyzed, and the thyroid hormone concentration after thyrotropin-releasing hormone test was evaluated. Serum thyroxine and free thyroxine levels were significantly lower in patients treated with carbamazepine and carbamazepine plus valproic acid than in the control subjects; serum thyroxine and free thyroxine concentrations were unaffected by valproic acid monotherapy. Serum triiodothyronine and free triiodothyronine concentrations were similar in the three groups of patients studied. Thyroid-stimulating hormone serum levels were normal in all patients, and the thyrotropin responses to the thyrotropin-releasing hormone were similar to control group. Our data suggest that children treated with carbamazepine may have subclinical signs of hypothyroidism, and these changes are more evident if carbamazepine is given in association with valproic acid, while no alteration in thyroid hormones can be found with valproic acid monotherapy. Thyroid-stimulating hormone and thyrotropin-releasing hormone levels do not seem to be affected by these drugs, suggesting that hypothalamic function is not affected in these children.

Serum leptin changes during weight loss in obese diabetic subjects with and without microalbuminuria.

To evaluate the changes of serum leptin levels after weight reduction in diabetic subjects with and without microalbuminuria, we studied 10 obese healthy subjects, 12 obese diabetics with persistent microalbuminuria and 10 obese diabetic subjects without microalbuminuria. Obese diabetic patients with microalbuminuria showed serum leptin levels significantly higher than normoalbuminuric diabetics, while no difference was found between obese diabetics without microalbuminuria and healthy controls. All obese subjects followed a 12-month intensive weight reduction program during which the mean change in body mass index was similar between obese diabetic and obese healthy subjects (obese diabetics without microalbuminuria: 35.2+/-4.3 vs 29.9+/-4.1, p<0.05; obese diabetics with microalbuminuria: 35.7+/-3.9 vs 30.3+/-4.0, p<0.05; obese healthy subjects: 35.5+/-4.0 vs 30.1+/-3.9, p<0.05). The mean changes in serum leptin levels tended to be similar in two groups of subjects studied (obese diabetics without microalbuminuria: 37.6+/-4.1 vs 19.7+/-4.9, p<0.001; obese healthy subjects: 37.1+/-4.3 vs 20.1+/-5.1, p<0.001); obese microalbuminuric subjects showed higher leptin levels (42.4+/-4.0 vs 30.3+/-4.2, p<0.001) than normoalbuminuric diabetic and obese healthy subjects. In conclusion, during weight loss, independently from the quality of metabolic control, serum leptin concentrations declined in both groups of obese diabetics. The changes of leptin in diabetics seem to be similar to those observed in healthy obese subjects.

Effect of anticonvulsant drugs on interleukins-1, -2 and -6 and monocyte chemoattractant protein-1.

In order to evaluate whether treatment with valproic acid or carbamazepine can modify interleukins and monocyte chemoattractant protein-1, we studied 40 epileptic children and adolescents. We evaluated the patients before and after 1 year of therapy. At the end of follow-up, the patients showed a significant increase of the production of interleukin-1alpha, interleukin-1beta, interleukin-6, and monocyte chemoattractant protein-1; interleukin-2 production was significantly higher only in patients receiving carbamazepine. In conclusion, antiepileptic drugs can influence the immune system by modifying interleukin and chemokine concentrations; these changes seem to be independent of the serum concentrations of these drugs.

Discontinuation of anticonvulsant therapy in children with partial epilepsy.

To evaluate when it is possible to discontinue anticonvulsant treatment in children with cryptogenic partial epilepsy, the authors studied 89 epileptic children divided into two groups: Group A, 45 children whose therapy was discontinued after 1 year from the last seizure; and Group B, 44 children whose therapy was stopped after 2 years from the last seizure. After 5 years of follow-up, the recurrence rate was similar in the two groups of patients (Group A, 28.8%; Group B, 25%). It is safe to discontinue the anticonvulsant therapy in children with cryptogenic partial epilepsy who were seizure free for only 1 year.

Vascular endothelial growth factor (VEGF) in children, adolescents and young adults with Type 1 diabetes mellitus: relation to glycaemic control and microvascular complications.

AIMS: To evaluate serum levels of vascular endothelial growth factor (VEGF) in a large group of children, adolescents and young adults with Type 1 diabetes mellitus to investigate whether increased VEGF concentrations are associated with long-term glycaemic control and microvascular complications. METHODS: The study involved 196 patients with Type 1 diabetes mellitus (age range 2-24 years, onset of diabetes before the age of 12 years, duration of disease longer than 2 years), without clinical and laboratory signs of microvascular complications; they were divided into three groups (group 1 - n = 37, age < 6 years; group 2 - n = 71, age 6-12 years; group 3 - n = 88, age > 12 years). Fifty-three adolescents and young adults (age 16.1-29.7) with different grades of diabetic retinopathy and microalbuminuria were also selected (group 4). A total of 223 healthy controls were matched for age and sex with each group of patients with diabetes mellitus. RESULTS: VEGF serum levels were significantly increased in pre-school and pre-pubertal children with diabetes as well as in pubertal patients compared to controls. VEGF concentrations were markedly increased in adolescents and young adults with microvascular complications compared with both healthy controls and diabetic patients without retinopathy or nephropathy. Multivariate analysis showed that elevation of VEGF in serum was an independent correlate of complications. One-year mean HbA1c values were significantly correlated with VEGF concentrations (r = 0.372; P < 0.01). Children with HbA1c levels greater than 10% had significantly higher VEGF concentrations when compared with matched patients whose HbA1c levels were lower than 10%. In poorly controlled diabetic children (HbA1c > 10%), long-term (2 years) improvement of glycaemic control (aiming at HbA1c < 7%) resulted in a significant reduction of VEGF levels. CONCLUSIONS: VEGF serum concentrations are increased in prepubertal and pubertal children with diabetes. Glycaemic control influences VEGF serum levels. Severity of microvascular complications is associated with marked increase of VEGF concentrations in the serum of these patients.

Leptin concentration in non-obese and obese children with type 1 diabetes mellitus.

Leptin, the product of the ob gene, is an adipocyte-derived hormone that positively correlates with body fat percantage and body mass index (BMI). There are many data which demonstrate a significant relationship between leptin and insulin, but the mechanism underlying the changes of leptin induced by insulin and vice versa remains to be studied in more detail. In this review, we analysed the data on the behaviour of serum leptin levels in non-obese and obese children with type 1 diabetes mellitus. It has been shown that the diminished serum leptin concentrations in patients with newly discovered insulin-dependent diabetes mellitus (IDDM) could be caused by insulin deficiency and/or increased lipolysis. Moreover, while in some studies in diabetic children with good metabolic control the serum leptin levels are similar to those of healthy children, in other studies children with IDDM have leptin levels higher than non diabetic children; it is possible that in some diabetic children intensified insulin therapy could cause chronic hyperinsulinemia with high leptin levels. The mean serum leptin concentrations in the obese diabetic subjects were significantly higher when compared with non-obese diabetics. Obese diabetic patients showed no significant differences in leptin concentrations in comparison to the non diabetic obese group matched by age, sex and BMI. In obese diabetics, during weight loss, independent of the quality of metabolic control, serum leptin concentration declines. The changes of leptin in diabetes seem to be similar to those observed in healthy obese subjects.

Serum leptin changes in epileptic patients who gain weight after therapy with valproic acid.

Weight gain has been recognized as an adverse effect of valproic acid therapy, but there are are no data about serum leptin levels in patients receiving this drug. To evaluate if valproic acid treatment in epileptic patients in whom obesity develops modifies serum levels of insulin and leptin, 40 female patients with epilepsy were evaluated before therapy and after 1 year of therapy. At the end of follow-up, 15 patients were obese and showed higher serum leptin and insulin levels than patients who did not gain weight. As in other types of obesity, elevation of serum leptin concentrations is related to the increase in body mass index.

Calcium metabolism in adolescents and young adults with type 1 diabetes mellitus without and with persistent microalbuminuria.

Alterations in calcium metabolism can be demonstrated in the course of insulin-dependent diabetes mellitus. In order to clarify if the presence of persistent microalbuminuria (MA) can affect the main parameters of calcium metabolism, we studied 22 diabetic adolescents and young adults with persistent MA and compared them with 24 patients without MA and 24 healthy controls. Mean values of serum calcium, phosphorus and magnesium were similar in diabetic children and young adults without persistent MA and in controls. In addition, the mean values of PTH and 25-OHD, 1,25 (OH)2D3 and OC did not differ between these diabetics and controls. Diabetics with persistent MA showed no significant difference from the values of either controls or the group of diabetics without persistent MA for the mean values of serum calcium, phosphorus and magnesium and PTH. In contrast, diabetics with persistent MA had significantly (p<0.01) lower 25-OHD (26.5+/-5.2 ng/ml) and 1,25 (OH)2D3 (24.7+/-5.6 pg/ml) as well as OC levels (9.8+/-2.5 ng/ml; p<0.001) than controls (38.1+/-4.9 ng/ml, 40.7+/-6.4 pg/ml and 16.5+/-5.8 ng/ml, respectively) and subjects with normoalbuminuria (36.0+/-4.5 ng/ml, 38.8+/-8.9 pg/ml and 14.5+/-3.2 ng/ml). In conclusion, our study suggests that abnormalities in 25-OHD, 1,25(OH)2D3 and OC can be present in diabetic adolescents and young adults with incipient nephropathy.

Leptin levels in non-obese and obese children and young adults with type 1 diabetes mellitus.

OBJECTIVE: To evaluate serum leptin levels in children and young adults with type 1 (insulin-dependent) diabetes mellitus and to investigate whether they are different in prepuberty, puberty and young adulthood. DESIGN: Three groups of diabetics (prepubertal, pubertal and young adults) subdivided into obese and non-obese were studied. Three groups of healthy subjects matched for sex, age and body mass index served as controls. RESULTS: Diabetic patients had serum leptin concentrations similar to those of controls in all three groups. A small non-significant increase in leptin from the prepubertal to the young adult age group for both diabetics and controls was found. A significant association of serum leptin level with body mass index (P < 0.001), female sex (P < 0.001) and age (P < 0.01) in both the diabetic and control group was present. Insulin-dependent diabetes was not associated with higher leptin concentration. CONCLUSIONS: Serum leptin concentrations are similar in diabetic patients and healthy controls. The association between obesity and leptin concentration was similar in the diabetic and non-diabetic subjects. Type 1 diabetes mellitus does not modify serum leptin concentration.

Controversies on the prevention of diabetic nephropathy.

Renal function declines progressively in patients with diabetic nephropathy and the decline may be slowed by some preventive interventions. Optimized and intensive insulin therapy delays the onset and slows the progression of diabetic nephropathy. Moreover, dietary restriction, avoiding a high protein intake, could be effective in reducing glomerular hyperfiltration. Finally, there is evidence that angiotensin-converting enzyme inhibitors reduce renal damage by one or more mechanisms independent of their antihypertensive effects. Some controversial aspects of the prevention of diabetic kidney disease are presented and discussed.

Serum lipids and lipoproteins in patients treated with antiepileptic drugs.

The concentration levels of serum lipids and lipoproteins were measured in three groups of children and adolescents treated with antiepileptic drugs: carbamazepine (14 patients), phenobarbital (20 patients), and valproic acid (20 patients). Patients treated with these drugs revealed significant changes in lipids and lipoproteins, but when the authors reevaluated the three groups of children 1 year after the end of treatment, a complete return to normal of all parameters was observed. These data demonstrate that the changes induced by these drugs are transient and reversible.