Celiac disease in children and adolescents with type I diabetes: importance of hypoglycemia

BACKGROUND

Symptomatic hypoglycemia is an unavoidable problem in the treatment of type I diabetes. Celiac disease is associated with malabsorption and may therefore represent an important risk factor.

METHODS

The frequency of symptomatic hypoglycemia in patients with type I diabetes and celiac disease (cases) was compared with those of patients who had diabetes without celiac disease (controls). For this purpose, each case was matched for age, sex, and duration of disease with one to two control patients. Indices of metabolic control (hemoglobin [Hb]A1c, frequency of hypoglycemia, and total insulin requirement) were retrieved for the 18 months before and after diagnosis of celiac disease.

RESULTS

Eighteen patients (6 males and 12 females) had diagnosed celiac disease and were matched with 26 control patients (10 males and 16 females). There was no difference in age (11.0 years; range, 1.8-21.9 vs. 13.1 years; range, 2.3-22; P = 0.3) and duration of disease (8.4 years; range, 1.2-19.3 vs. 8.3 years; range, 1.1-18.7; P = 0.3) between the two groups. During the 6 months before and after diagnosis of celiac disease the cases had significantly more hypoglycemic episodes than the controls (means +/- SD; 4.5+/-4 vs. 2.0+/-2.2 episodes/months, P = 0.01). This was reflected by a progressive reduction in insulin requirement over the 12 months before diagnosis reaching a nadir at time 0 (0.6+/-0.2 vs. 0.9+/-0.3, P = 0.05).

CONCLUSION

These data suggest that underlying celiac disease is associated with an increased risk of symptomatic hypoglycemia and that the introduction of a gluten-free diet with normalization of the intestinal mucosa may reduce its frequency.

Increased circulating nitric oxide in young patients with type 1 diabetes and persistent microalbuminuria: relation to glomerular hyperfiltration

Hyperglycemia has been causally linked to vascular and glomerular dysfunction by a variety of biochemical mechanisms, including a glucose-dependent abnormality in nitric oxide (NO) production and action. NO is a candidate for mediating hyperfiltration and the increased vascular permeability induced by diabetes. Serum nitrite and nitrate (NO2-+ NO3-) concentrations were assessed as an index of NO production in 30 adolescents and young adults with type 1 diabetes, 15 with and 15 without microalbuminuria (albumin excretion rate [AER] between 20 and 200 microg/min), compared with a well-balanced group of healthy control subjects. In all subjects, glomerular filtration rate (GFR) was determined by radionuclide imaging. Our study showed that NO2- + NO3- serum content and GFR values were significantly higher in microalbuminuric diabetic patients than in the other 2 groups. GFR was significantly and positively related to AER levels (r2 = 0.75, P < 0.0001), whereas NO2- + NO3- serum content was independently associated with both AER and GFR values (beta = 2.086, P = 0.05, beta = 1.273, P = 0.0085, respectively), suggesting a strong link between circulating NO, glomerular hyperfiltration, and microalbuminuria in young type 1 diabetic patients with early nephropathy. Interestingly, mean HbA1c, serum concentration was significantly higher in microalbuminuric than in normoalbuminuric diabetic subjects (P < 0.05) and was independently associated with AER values, suggesting a role for chronic hyperglycemia in the genesis of diabetic nephropathy. Moreover, HbA1c serum concentration was significantly and positively related to NO2 + NO3 serum content (r2 = 0.45, P = 0.0063) and GFR values (r2 = 0.57, P = 0.0011), suggesting that chronic hyperglycemia may act through a mechanism that involves increased NO generation and/or action. In conclusion, we suggest that in young type 1 diabetic patients with early nephropathy, chronic hyperglycemia is associated with an increased NO biosynthesis and action that contributes to generating glomerular hyperfiltration and persistent microalbuminuria.

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.

The effect of subclinical hypothyroidism on metabolic control in children and adolescents with Type 1 diabetes mellitus

AIMS

Associated autoimmune phenomena might influence metabolic control in children and adolescents with Type 1 diabetes mellitus. A retrospective case control study was performed in order to explore the effect of subclinical hypothyroidism on metabolic control in Type 1 diabetes mellitus.

PATIENTS AND METHODS

For this purpose each patient with Type 1 diabetes and subclinical hypothyroidism (cases) was matched for age, duration of disease and, if possible, for sex, with two to three diabetic patients without hypothyroidism (controls). Parameters of metabolic control such as HbA1c, total insulin requirement and frequency of symptomatic hypoglycaemia were retrieved for 12, 6 and 3 months before and after diagnosis of hypothyroidism.

RESULTS

Thirteen patients (two male/11 female) patients were diagnosed with subclinical hypothyroidism and were matched with 31 controls (nine male/22 female). There was no difference (mean and range) in terms of age (11.9 years (4.4-18.1) vs. 11.7 years (3.5-18.1), P = 0.9) and duration of disease (5.1 years (1.2-10.5) vs. 4.38 years (0.9-10.8), P = 0.6) between the two groups. There was no difference in HbA1c and total insulin requirement between the two groups at any time point of assessment (anova P = 0.8 and P = 0.1, respectively). Patients with hypothyroidism had significantly more symptomatic hypoglycaemic episodes during the 12 months before diagnosis (anova P = 0.05), increasing progressively during this time period and reaching a peak at time 0 (5.5+/-0.4 vs. 1.6+/-0.1 episodes/month, P = 0.01). No difference could be detected within 6 months of starting substitution therapy (2.4+/-0.2 vs. 1.6+/-0.1 episodes/week, P = 0.8).

CONCLUSIONS

These data suggest that subclinical hypothyroidism is associated with an increased risk of symptomatic hypoglycaemia. The prompt introduction of substitution therapy is recommended as it reduces its frequency.

Enhanced soluble CD40 ligand contributes to endothelial cell dysfunction in vitro and monocyte activation in patients with diabetes mellitus: effect of improved metabolic control

AIMS/HYPOTHESIS

Inflammation plays a pathogenic role in the development of accelerated atherosclerosis in diabetes. Soluble CD40 ligand (sCD40L) is enhanced in diabetes; however, the molecular mechanisms linking sCD40L to accelerated atherosclerosis in diabetes are still unclear. We tested the hypothesis that sCD40L may be involved in the vascular complications in diabetes and exerts its effect by triggering inflammatory reactions on mononuclear and endothelial cells (ECs).

METHODS

We studied 70 patients, 40 with type 2 and 30 with type 1 diabetes, with a history or physical examination negative for cardiovascular disease, and 40 non-diabetic and 30 healthy subjects, matched with the type 2 and type 1 diabetic patients, respectively. Plasma and serum sCD40L, and plasma soluble intercellular adhesion molecule-1, soluble vascular cell adhesion molecule-1, E-selectin and monocyte chemo-attractant protein-1 (MCP-1) were measured. Adhesion molecules and MCP-1 release, the ability to repair an injury in ECs, and O2- generation in monocytes were analysed in vitro after stimulation with serum from patients or controls.

RESULTS

Type 2 and type 1 diabetic patients had significantly higher sCD40L levels than controls. Furthermore, high sCD40L was associated with in vitro adhesion molecules and MCP-1 release, impaired migration in ECs and enhanced O2- generation in monocytes. Improved metabolic control was associated with a reduction of plasma sCD40L by 37.5% in 12 type 1 diabetic patients. Furthermore, elevated sCD40L in diabetic patients was significantly correlated with HbA1c levels.

CONCLUSIONS/INTERPRETATION

Upregulation of sCD40L as a consequence of persistent hyperglycaemia in diabetic patients results in EC activation and monocyte recruitment to the arterial wall, possibly contributing to accelerated atherosclerosis development in diabetes.

Monogenic Diabetes Accounts for 6.3% of Cases Referred to 15 Italian Pediatric Diabetes Centers During 2007 to 2012

CONTEXT

An etiologic diagnosis of diabetes can affect the therapeutic strategy and prognosis of chronic complications.

OBJECTIVE

The aim of the present study was to establish the relative percentage of different diabetes subtypes in patients attending Italian pediatric diabetes centers and the influence of an etiologic diagnosis on therapy.

DESIGN, SETTING, AND PATIENTS

This was a retrospective study. The clinical records of 3781 consecutive patients (age, 0 to 18 years) referred to 15 pediatric diabetes clinics with a diagnosis of diabetes or impaired fasting glucose from January 1, 2007 to December 31, 2012 were examined. The clinical characteristics of the patients at their first referral to the centers, type 1 diabetes-related autoantibodies, molecular genetics records, and C-peptide measurements, if requested for the etiologic diagnosis, were acquired.

MAIN OUTCOME MEASURES

The primary outcome was to assess the percentage of each diabetes subtype in our sample.

RESULTS

Type 1 diabetes represented the main cause (92.4%) of diabetes in this group of patients, followed by monogenic diabetes, which accounted for 6.3% of cases [maturity onset diabetes of the young (MODY), 5.5%; neonatal diabetes mellitus, 0.6%, genetic syndromes, 0.2%]. A genetic diagnosis prompted the transfer from insulin to sulphonylureas in 12 patients bearing mutations in the HNF1A or KCNJ11 genes. Type 2 diabetes was diagnosed in 1% of the patients.

CONCLUSIONS

Monogenic diabetes is highly prevalent in patients referred to Italian pediatric diabetes centers. A genetic diagnosis guided the therapeutic decisions, allowed the formulation of a prognosis regarding chronic diabetic complications for a relevant number of patients (i.e.,GCK/MODY), and helped to provide genetic counseling.

An ATP-binding mutation (G334D) in KCNJ11 is associated with a sulfonylurea-insensitive form of developmental delay, epilepsy, and neonatal diabetes

Mutations in the pancreatic ATP-sensitive K(+) channel (K(ATP) channel) cause permanent neonatal diabetes mellitus (PNDM) in humans. All of the K(ATP) channel mutations examined result in decreased ATP inhibition, which in turn is predicted to suppress insulin secretion. Here we describe a patient with severe PNDM, which includes developmental delay and epilepsy, in addition to neonatal diabetes (developmental delay, epilepsy, and neonatal diabetes [DEND]), due to a G334D mutation in the Kir6.2 subunit of K(ATP) channel. The patient was wholly unresponsive to sulfonylurea therapy (up to 1.14 mg . kg(-1) . day(-1)) and remained insulin dependent. Consistent with the putative role of G334 as an ATP-binding residue, reconstituted homomeric and mixed WT+G334D channels exhibit absent or reduced ATP sensitivity but normal gating behavior in the absence of ATP. In disagreement with the sulfonylurea insensitivity of the affected patient, the G334D mutation has no effect on the sulfonylurea inhibition of reconstituted channels in excised patches. However, in macroscopic rubidium-efflux assays in intact cells, reconstituted mutant channels do exhibit a decreased, but still present, sulfonylurea response. The results demonstrate that ATP-binding site mutations can indeed cause DEND and suggest the possibility that sulfonylurea insensitivity of such patients may be a secondary reflection of the presence of DEND rather than a simple reflection of the underlying molecular basis.

Circulating monocyte chemoattractant protein-1 and early development of nephropathy in type 1 diabetes

OBJECTIVES

To investigate the possible role of hyperglycemia-dependent monocyte chemoattractant protein (MCP)-1 biosynthesis in the pathophysiology of early nephropathy in type 1 diabetes.

RESEARCH DESIGN AND METHODS

We studied 30 patients with type 1 diabetes (15 with and 15 without microalbuminuria) compared with matched healthy control subjects. Plasma MCP-1 and plasma oxidant status (vitamin E, fluorescent products of lipid peroxidation [FPLPs], malondialdehyde [MDA]), HbA(1c), and albumin excretion rate [AER]) were evaluated at baseline. Furthermore, MCP-1, vitamin E, AER, and HbA(1c) were also analyzed in the microalbuminuric diabetic patients and in the healthy volunteers after 8 weeks of high-dose (600 mg b.i.d.) vitamin E treatment.

RESULTS

FPLPs, MDA, and MCP-1 were significantly higher, whereas vitamin E was significantly lower in patients with microalbuminuria and poorer glycemic control as compared with normoalbuminuric patients and healthy control subjects. Plasma MCP-1 was positively correlated with HbA(1c), FPLPs, MDA, and AER, whereas plasma MCP-1 showed an inverse correlation with vitamin E. Interestingly, both MCP-1 and AER decreased significantly after vitamin E treatment, despite no changes in HbA(1c) values.

CONCLUSIONS

This study suggests that prolonged hyperglycemia may lead to early renal complications in type 1 diabetes by inducing MCP-1 biosynthesis via enhanced oxidative stress. Long-term treatment of high-dose vitamin E significantly decreased MCP-1, thus providing a rationale basis for evaluating vitamin E supplementation as therapy adjuvant to conventional insulin treatment in type 1 diabetic patients in whom an acceptable glycemic control is difficult to achieve despite appropriate insulin treatment.

Insulin degludec in combination with bolus insulin aspart is safe and effective in children and adolescents with type 1 diabetes

Insulin degludec (IDeg) once-daily was compared with insulin detemir (IDet) once- or twice-daily, with prandial insulin aspart in a treat-to-target, randomized controlled trial in children 1-17 yr with type 1 diabetes, for 26 wk (n = 350), followed by a 26-wk extension (n = 280). Participants were randomized to receive either IDeg once daily at the same time each day or IDet given once or twice daily according to local labeling. Aspart was titrated according to a sliding scale or in accordance with an insulin:carbohydrate ratio and a plasma glucose correction factor. Randomization was age-stratified: 85 subjects 1-5 yr. (IDeg: 43), 138 6-11 yr (IDeg: 70) and 127 12-17 yr (IDeg: 61) were included. Baseline characteristics were generally similar between groups overall and within each stratification. Non-inferiority of IDeg vs. IDet was confirmed for HbA1c at 26 wk; estimated treatment difference (ETD) 0.15% [-0.03; 0.32]95% CI . At 52 wk, HbA1c was 7.9% (IDeg) vs. 7.8% (IDet), NS; change in mean FPG was -1.29 mmol/L (IDeg) vs. +1.10 mmol/L (IDet) (ETD -1.62 mmol/L [-2.84; -0.41]95% CI , p = 0.0090) and mean basal insulin dose was 0.38 U/kg (IDeg) vs. 0.55 U/kg (IDet). The majority of IDet treated patients (64%) required twice-daily administration to achieve glycemic targets. Hypoglycemia rates did not differ significantly between IDeg and IDet, but confirmed and severe hypoglycemia rates were numerically higher with IDeg (57.7 vs. 54.1 patient-years of exposure (PYE) [NS] and 0.51 vs. 0.33, PYE [NS], respectively) although nocturnal hypoglycemia rates were numerically lower (6.0 vs. 7.6 PYE, NS). Rates of hyperglycemia with ketosis were significantly lower for IDeg vs. IDet [0.7 vs. 1.1 PYE, treatment ratio 0.41 (0.22; 0.78)95% CI , p = 0.0066]. Both treatments were well tolerated with comparable rates of adverse events. IDeg achieved equivalent long-term glycemic control, as measured by HbA1c with a significant FPG reduction at a 30% lower basal insulin dose when compared with IDet. Rates of hypoglycemia did not differ significantly between the two treatment groups; however, hyperglycemia with ketosis was significantly reduced in those treated with IDeg.

Prevalence of hypospadias in Italy according to severity, gestational age and birthweight: an epidemiological study

Background

Hypospadias is a congenital displacement of the urethral meatus in male newborns, being either an isolated defect at birth or a sign of sexual development disorders. The aim of this study was to assess the prevalence rate of hypospadias in different Districts of Italy, in order to make a comparison with other countries all over the world.

Methods

We reviewed all the newborns file records (years 2001–2004) in 15 Italian Hospitals.

Results

We found an overall hypospadias prevalence rate of 3.066 ± 0.99 per 1000 live births (82.48% mild hypospadias, 17.52% moderate-severe). In newborns Small for Gestational Age (birthweight < 10^th percentile) of any gestational age the prevalence rate of hypospadias was 6.25 per 1000 live births. Performing multivariate logistic regression analysis for different degrees of hypospadias according to severity, being born SGA remained the only risk factor for moderate-severe hypospadias (p = 0.00898) but not for mild forms (p > 0.1).

Conclusion

In our sample the prevalence of hypospadias results as high as reported in previous European and American studies (3–4 per 1000 live births). Pathogenesis of isolated hypospadias is multifactorial (genetic, endocrine and environmental factors): however, the prevalence rate of hypospadias is higher in infants born small for gestational age than in newborns with normal birth weight.

Controlled study in diabetic children comparing insulin-dosage adjustment by manual and computer algorithms

A controlled trial of a new microprocessor device for insulin-dosage adjustment was undertaken in two matched groups of a priori well-controlled diabetic children. A prospective study design with three equal 8-wk periods was used. In the first period, both groups used manual methods for insulin-dosage adjustment after manual criteria. In the second period, one group of children adjusted insulin dosage by computer algorithms, whereas the other continued to use manual methods. In the third period, both groups again adjusted insulin by traditional methods. Mean premeal glycemia and glycosylated hemoglobin levels did not change in either group throughout the study. During the second period, episodes of hypoglycemia were more frequent in children without the computer than in those who used the device. In keeping with the latter outcome, the group that used the microprocessor device was given less insulin in the second period than the first (0.88 +/- 0.02 vs. 0.94 +/- 0.02 U.kg-1.day-1, P less than 0.0001) and in comparison to the control group of patients who concurrently were given an increased insulin dose in the second period compared with the first. This study showed that insulin treatment through specific computer-mediated dosage-adjusting algorithms was safe and minimized hypoglycemia by effectively accommodating seasonally changing insulin requirements. We recommend the device to help diabetic children and their families in the care of insulin-dependent diabetes.

Molecular characterization of 6 unrelated Italian patients with 5alpha-reductase type 2 deficiency

Steroid 5alpha-reductase (5alphaR) deficiency (OMIM number #264600) is a rare 46,XY disorder of sex differentiation caused by mutations in the 5alphaR type 2 gene (SRD5A2) resulting in dihydrotestosterone deficiency during fetal development. We report on the analysis of the SRD5A2 gene in 6 unrelated 46,XY Italian patients with external genitalia morphology ranging from predominantly female to nearly completely male. Three subjects were seen and assessed at birth, 1 patient was referred to us before puberty, and 2 at postpubertal age. Six different causative mutations (5 missense and 1 nonsense) and a rare polymorphism were identified. Four patients presented homozygous single-base substitutions. These SRD5A2 mutations were located in exon 2 (variant Cys133Gly), exon 4 (Gly196Ser and Ala207Asp) and exon 5 (Tyr235Phe). A fifth subject was a compound heterozygote who carried a nonsense mutation in exon 1 (Trp53X) and a second SRD5A2 alteration in exon 5 (Tyr235Phe). The final patient presented a mutation in only 1 allele (Gly34Trp) together with the Ala49Thr variant. The molecular characterization of these patients made it possible to identify novel mutations and to confirm, before gender assignment or any surgical approach, the suspected 5alphaR deficiency in 2 newborns, 1 of whom had inconclusive hormonal data. 5alphaR deficiency in subjects without parental consanguinity and the presence of compound heterozygotic patients suggest that SRD5A2 mutations carrier frequency may be higher than previously thought.

Health-related quality of life and treatment preferences in adolescents with type 1 diabetes. The VIPKIDS study

A multi-centre, observational, cross-sectional study was carried out to determine whether the health-related quality of life (HRQOL) of adolescents with type 1 diabetes is affected by different insulin treatment systems, and which features of HRQOL are impacted by the respective insulin treatment. The study regarded 577 adolescents, aged 10-17 years, with type 1 diabetes treated with continuous subcutaneous insulin infusion (CSII) (n = 306) or multiple daily injections (MDI) (n = 271). The Insulin Delivery System Rating Questionnaire was validated in Italian and was self-completed by the subjects during a routine visit to the centres. Subjects were compared following the domains of the questionnaire. Good HRQOL was seen in subjects treated with either MDI or CSII. Significant differences were not found in the domains for general diabetes, including diabetes worries, social burden and psychological well-being. Multiple quantile regression analysis showed that CSII confers significant advantages in terms of HRQOL with improvements in treatment satisfaction, perceived clinical efficacy and reduction in treatment interference with daily activities. This favourable impact was more evident in subjects reporting lower HRQOL scores, suggesting that CSII may be especially useful for individuals perceiving a poor HRQOL. Analysis of the domains indicated that CSII was associated with a higher HRQOL than MDI. Life-course HRQOL evaluation using a standardised questionnaire can ensure better chronic disease management. This is particularly important when providing individualised care for adolescents, as they become increasingly responsible for managing their diabetes.

Early diagnosis of 5alpha-reductase deficiency in newborns

5Alpha-reductase-2 deficiency is a rare autosomal recessive form of 46,XY disorders of sex differentiation (DSD), caused by mutations in the steroid 5alpha-reductase type 2 gene (SRD5A2), presenting at birth with variable degrees of undervirilization. We report on three Italian newborns with 46,XY DSD in whom the evaluation of testosterone, dihydrotestosterone, testosterone/dihydrotestosterone (T/DHT) ratio and molecular analysis of the 5alpha-reductase type 2 gene was made in their first month of life. Baseline T/DHT ratio suggested 5alpha-reductase-2 deficiency; the diagnosis was confirmed by molecular genetics (homozygous mutation in exon 4 [G196S], heterozygous mutation in exon 1 and 5 [W35X/Y235F], heterozygous mutation plus polymorphism in exon 1 [G34W/A49T]). Proper investigation permitted early reassignment to male sex in two babies, assigned to female sex just after birth. In infancy, the T/DHT ratio, assessed by suitable assay methods and evaluated by age-appropriate reference values, seems to be able to select newborns affected by 5alpha-reductase-2 deficiency. Molecular analysis of the SRD5A2 gene should be warranted in newborns with abnormal ratio before sex assignment.

Infant and toddler type 1 diabetes: complications after 20 years' duration

OBJECTIVE

To compare the effect of the prepubertal duration of diabetes on the occurrence of complications in two groups of patients after the same number of years of the disease.

RESEARCH DESIGN AND METHODS

This multicenter study enrolled 105 patients aged 16-40.3 years; 53 were prepubertal at diagnosis (aged 0-3) and 52 were pubertal (Tanner stage) and aged 9-14.9. The mean duration of disease was 19.8 and 19.5 years for prepubertal and pubertal patients, respectively. In all patients, retinal photographs were taken and centrally graded. Urinary albumin excretion (UAE; 86 case subjects), blood pressure (BP; 89 case subjects), and lifetime HbA(1c) (72 case subjects) were also evaluated.

RESULTS

The prevalence of diabetic retinopathy (DR) was higher in pubertal than in prepubertal patients, both for any grade DR (71 vs. 40%, P = 0.002) and for mild or more severe DR (P = 0.005). The prevalence of abnormal UAE was not different in the two groups. Hypertension was found only in three patients, all pubertal at diagnosis. In the small group with moderate-to-severe DR, lifetime HbA(1c) levels, as percentages above the upper normal reference value, were higher (P < 0.01) in prepubertal than in pubertal patients.

CONCLUSIONS

If diabetes is diagnosed in infants or toddlers and the prepubertal duration of diabetes is very long, the patients seem to be protected against DR. This protection disappears if lifetime metabolic control is bad. Instead, when onset is at puberty, the DR risk is higher and less dependent on metabolic control and may be influenced by age-related factors, such as BP.

Identification and characterization of different SHOX gene deletions in patients with Leri-Weill dyschondrosteosys by MLPA assay

Deletions of the SHOX gene (Xp22-Yp11.3) are associated with Leri-Weill dyschondrosteosys (LWD) and idiopathic short stature. It has been estimated that SHOX deletions occur in 1,000-2,000 individuals in the total population, suggesting that this alteration should be investigated in all cases with unexplained short stature. SHOX deletions are currently investigated using fluorescence in situ hybridization (FISH) or molecular analysis of intragenic CA repeats. However, both techniques show some limitations. In the present study, the use of the multiple ligation probe amplification (MLPA) assay for the identification and characterization of SHOX deletions in 15 LWD patients, 3 of which carriers of chromosome abnormalities involving the SHOX gene, is reported. MLPA analysis demonstrated the heterozygous deletion of SHOX in seven patients (46.6%), disclosing the presence of two different proximal breakpoints. In patients with abnormal karyotype, MLPA analysis was able to identify the chromosomal rearrangement, showing, in addition to the SHOX deletions, the gain or loss of other genes mapped on the X and Y chromosomes. Since MLPA analysis can be carried out on a simple buccal swab, avoiding invasive peripheral blood collection, this technique represents a fast, simple and high throughput approach in the screening of SHOX deletions, able to provide more information as compared to FISH and microsatellite analysis.

Serum angiogenin concentrations in young patients with diabetes mellitus

BACKGROUND

Angiogenin serum levels were measured in a large group of type 1 diabetic young patients, looking at whether increased Angiogenin concentrations are associated with long-term glycemic control and microvascular complications.

MATERIALS AND METHODS

Four groups of patients were compared to 223 age- and sex- matched healthy controls: 196 type 1 diabetic patients (age range 3-24 years, onset of diabetes before the age of 12 years; duration of disease longer than 2 years), without microvascular complications were divided into three groups on the basis of age (group 1, n = 37, age < 6 years; group 2, n = 71, age 6-12 years; group 3, n = 88, age > 12 years); 53 adolescents and young adults (age 16.1-29.7 years) with diabetic microvascular complications (background, preproliferative or proliferative retinopathy, albumin excretion rate 20-200 microg min-1) (group 4).

RESULTS

Angiogenin serum levels were significantly increased in diabetic pre-school and pre-pubertal children, and particularly elevated in pubertal subjects compared with age- and sex-matched controls. Adolescents and young adults with microvascular complications had very high angiogenin concentrations. One-year mean HbA1c values were correlated with angiogenin levels (r = 0.389; p < 0.01). In poorly controlled diabetics (HbA1c > 10%), long-term (2 years) improvement of glycemic control determined a significant reduction of angiogenin concentrations in both pre-school and pre-pubertal children as well as in pubertal youngsters.

CONCLUSIONS

Angiogenin serum concentrations are increased in diabetic children even before puberty. Severity of microvascular complications is associated with markedly increased angiogenin serum levels. Long-term tight glycemic control determines a consistent reduction of angiogenin concentrations.

Homocysteine levels during fasting and after methionine loading in adolescents with diabetic retinopathy and nephropathy

OBJECTIVE

To assess plasma homocysteine levels in adolescents and young adults with type 1 (insulin-dependent) diabetes with and without microvascular complications.

STUDY DESIGN

Homocysteine levels were measured during fasting and after methionine loading in plasma of 61 patients with onset of diabetes before the age of 12 years and duration of disease longer than 7 years. They had an albumin excretion rate (AER) between 20 and 200 microg/min in 2 of 3 overnight urine collections in a period of 6 months and/or retinopathy. Patients with persistent microalbuminuria were divided into 2 groups: subjects with AER of 20 to 70 microg/min and patients with AER of 70 to 200 microg/min. Adolescents (n = 54) without signs of diabetic retinopathy or nephropathy and matched control subjects (n = 63) were also studied.

RESULTS

Homocysteine concentrations before and after methionine load were higher in adolescents with diabetic complications than in healthy subjects (fasting values: 12. 4 +/- 7.9 micromol/L vs 7.8 +/- 4.2 micromol/L; P <.01; after methionine load: 28.1 +/- 13.2 micromol/L vs 16.6 +/- 7.3 micromol/L; P <.005). Values of 11.9 micromol/L or higher were considered to constitute fasting hyperhomocysteinemia. The increase of homocysteine concentrations was particularly evident in young diabetic patients with AER >70 microg/min (fasting values: 14.7 +/- 5.6 micromol/L; after methionine load: 34.2 +/- 12.6 micromol/L) and in patients with proliferative retinopathy (fasting values: 15.1 +/- 5.0 micromol/L; after methionine load: 36.8 +/- 12.5 micromol/L).

CONCLUSIONS

Increased plasma homocysteine concentrations may contribute to increased morbidity and death from cardiovascular disease in adolescents and young adults with diabetic retinopathy and nephropathy.

Increased vascular endothelial growth factor serum concentrations may help to identify patients with onset of type 1 diabetes during childhood at risk for developing persistent microalbuminuria

This study was designed to evaluate whether vascular endothelial growth factor serum concentrations may identify adolescents with onset of type 1 diabetes during childhood at greater risk to develop persistent microalbuminuria and incipient diabetic nephropathy. In January 1989, vascular endothelial growth factor serum levels were measured in 101 normoalbuminuric diabetic children and adolescents (aged 7-14.9 yr; onset of diabetes before age 18 yr; duration of diabetes >7 yr). Participants were clinically examined at baseline and annually thereafter. Vascular endothelial growth factor serum concentrations were measured every year during the 8-yr follow-up period. Over 8 yr, 11 of 101 patients (10.9%) developed persistent microalbuminuria; no patient developed overt nephropathy. The risk of developing microalbuminuria was higher in children with increased vascular endothelial growth factor serum levels (using 160 pg/ml as the arbitrary cut-off point; group 1) compared with those with normal vascular endothelial growth factor serum levels at the beginning of the study (group 2; 19.2 vs. 2.0%; P < 0.01; sensitivity, 90.9%; specificity, 53.3%). The odds ratio for the occurrence of microalbuminuria after adjustment for confounding variables (albumin excretion rate, sex, hemoglobin A(1c), mean blood pressure, cholesterol, and triglycerides) in type 1 diabetic adolescents with elevated vascular endothelial growth factor serum levels was 4.1 (95% confidence interval, 2.0-10.9). These results suggest that vascular endothelial growth factor serum concentrations may be one of the predictors and risk factors for microalbuminuria and incipient diabetic nephropathy in adolescents and young adults with onset of diabetes during childhood. Persistently increased vascular endothelial growth factor serum levels may help to identify normotensive, normoalbuminuric patients with type 1 diabetes who are predisposed to develop persistent microalbuminuria later in life.

Serum and urinary nitrites and nitrates and Doppler sonography in children with diabetes

OBJECTIVE

The aim of the present study was to evaluate serum and urinary nitric oxide (NO) concentrations in children and adolescents with diabetes compared with age-matched healthy control subjects to find out whether Doppler ultrasonography could be used to detect changes in renal resistive indexes (RIs) in children with diabetes and to assess whether there are correlations between these parameters and NO excretion.

RESEARCH DESIGN AND METHODS

We studied 42 children with type 1 diabetes and 41 matched healthy control subjects, both divided into prepubertal or pubertal children. Serum and urinary nitrite and nitrate (NO2-+NO3-) concentrations were evaluated as an index of NO production. Doppler ultrasonographic registration of intrarenal RI was performed.

RESULTS

Compared with healthy control subjects, children with diabetes had significantly increased concentrations of serum (30.26 +/- 6.52 vs. 24.47 +/- 7.27 mmol/l, P = 0.001) and urinary NO2-+NO3- (345.07 +/- 151.35 vs. 245.86 +/- 80.25 mmol/l, P = 0.002); the same was true for Doppler RI values (0.64 +/- 0.03 vs. 0.60 +/- 0.04, P = 0.035). This occurs in both prepubertal and the pubertal children. A significant positive correlation was found between serum and urinary NO2-+NO3- levels (P = 0.002, r = 0.374). Serum NO2-+NO3- concentrations also correlated positively with Doppler RI (P = 0.032, r = 0.262) and HbA1c (A1C) (P = 0.004, r = 0.329); urinary NO2-+NO3- concentrations correlated positively with A1C (P = 0.001, r = 0.394). Doppler RI correlated positively with A1C (P = 0.000, r = 0.424).

CONCLUSIONS

This study demonstrates that in children with diabetes, chronic hyperglycemia may act through a mechanism that involves increased NO production and/or action and contributes to generating intrarenal hemodynamic abnormalities, which are detectable by Doppler ultrasonography even in early diabetic nephropathy.

High frequency of diabetic ketoacidosis at diagnosis of type 1 diabetes in Italian children: a nationwide longitudinal study, 2004-2013

This longitudinal population-based study analyses the frequency of diabetic ketoacidosis (DKA) at type 1 diabetes diagnosis in Italian children under 15 years of age, during 2004-2013. DKA was defined as absent (pH ≥ 7.30), mild/moderate (7.1 ≤ pH < 7.30) and severe (pH < 7.1). Two multiple logistic regression models were used to evaluate the time trend of DKA frequency considered as present versus absent and severe versus absent, adjusted for gender, age group and geographical area of residence at diagnosis. Overall, 9,040 cases were ascertained. DKA frequency was 40.3% (95%CI: 39.3-41.4%), with 29.1% and 11.2% for mild/moderate and severe DKA, respectively. Severe DKA increased significantly during the period (OR = 1.03, 95%CI: 1.003-1.05). Younger-age children and children living in Southern Italy compared to Central Italy were at significantly higher risk of DKA and severe DKA. Family history of type 1 diabetes and residence in Sardinia compared to Central Italy were significantly associated with a lower probability of DKA and severe DKA. The high frequency of ketoacidosis in Italy over time and high variability among age groups and geographical area of residence, strongly suggests a continuing need for nationwide healthcare strategies to increase awareness of early detection of diabetes.

Effects of vitamin E supplementation on intracellular antioxidant enzyme production in adolescents with type 1 diabetes and early microangiopathy

Defective intracellular antioxidant enzyme production (IAP) has been demonstrated in adults with diabetic nephropathy. To evaluate the effects on IAP of vitamin E administration in adolescents with type 1 diabetes and early signs of microangiopathy, 12 adolescents (aged 11-21 y; diabetes duration 10-18) were studied. Eight had retinopathy [background (four), preproliferative (three), or proliferative (one)], four had persistent microalbuminuria, and seven had both. Skin fibroblasts were obtained by biopsies and cultured in Dulbecco's modified Eagle's medium. CuZn superoxide dismutase (SOD), MnSOD, catalase (CAT), and glutathione-peroxidase (GPX) activity and mRNA expression were measured before and after 3 mo of synthetic vitamin E supplementation (600 mg twice daily); on both occasions, IAP was evaluated at different ex vivo glucose concentrations (5 and 22 mM). Ten adolescents with type 1 diabetes (aged 12-20 y) without angiopathy and eight healthy volunteers (aged 15-22 y) participated as control subjects. Vitamin E serum levels were measured throughout the study. In normal glucose concentrations, CuZnSOD, MnSOD, CAT, and GPX activity and mRNA expression were not different among the groups. In high glucose, CuZnSOD activity and mRNA increased similarly in all groups [angiopathics: 0.96 +/- 0.30 U/mg protein; 9.9 +/- 3.2 mRNA/glyceraldehyde-3-phosphate dehydrogenase). CAT and GPX activity and mRNA did not increase in high glucose only in adolescents with angiopathy (0.35 +/- 0.09; 4.2 +/- 0.1 and 0.52 +/- 0.14; 2.4 +/- 0.9, respectively). MnSOD did not change in any group. Vitamin E supplementation had no effect on any enzymatic activity and mRNA in both normal and hyperglycemic conditions. Adolescents with early signs of diabetic angiopathy have defective IAP and activity, which are not modified by vitamin E.