A comparative study using insulin pump therapy and continuous glucose monitoring in newly diagnosed very young children with type 1 diabetes: it is possible to bend the curve of HbA1c

AIMS

The target of metabolic control (HbA1c < 7% or 53 mmol/mol) recommended by the ADA and ISPAD is attained by 30% of children with Type 1 Diabetes (T1D). Advances in technologies for T1D aim to improve metabolic outcomes and reduce complications. This observational study assesses the long-term outcomes of advanced technologies for treatment of T1D compared to conventional approach started at onset in a group of very young children with T1D.

METHODS

54 patients with less 4 years old at onset of T1D were enrolled and followed for up to 9 years after diagnosis. 24 subjects started continuous subcutaneous insulin (CSII) treatment and 30 subjects received MDI therapy from onset. Auxological data, HbA1c and total daily insulin dose (TDD/kg) have been collected at admission and every 4 months. HbA1cAUC>6%, rates of acute complications, glycemic variability indices and glucometrics were also recorded.

RESULTS

Patients with CSII therapy had significantly lower mean HbA1c values compared to subjects receiving MDI treatment. CSII approach also recorded lower mean HbA1cAUC>6% and TDD/kg than MDI therapy. At the last download data, the time in range (TIR) was higher in patients with CSII and hyperglycemia events were lower. Better glycemic variability indices have been described during CSII therapy, including mean glycemia, standard deviation, coefficient of variation (CV), glycemia risk index (GRI) and high blood glucose index (HBGI). There was no statistically significant difference between frequency of severe hypoglycemia and ketoacidosis episodes between groups.

CONCLUSIONS

Early initiation of diabetes technologies is safe and able to determine a better long term glycemic control in young children with T1D. It also allows to flatten the trajectory of HbA1c, probably reducing microvascular, macrovascular and neurological complications of diabetes in this very peculiar age group.

Non-Occlusive Mesenteric Ischemia in Children With Diabetic Ketoacidosis: Case Report and Review of Literature

INTRODUCTION

Despite the use of technology, recurrent diabetic ketoacidosis (DKA) prevention remains an unmet need in children and adolescents with T1D and may be accompanied by life-threatening acute complications. We present a rare case of non-occlusive mesenteric ischemia (NOMI) with overt manifestation after DKA resolution and a discussion of recent literature addressing DKA-associated NOMI epidemiology and pathogenesis in children and adolescents.

CASE PRESENTATION

A 13-year-old female with previously diagnosed T1D, was admitted at our emergency department with hypovolemic shock, DKA, hyperosmolar state and acute kidney injury (AKI). Mildly progressive abdominal pain persisted after DKA correction and after repeated ultrasound evaluations ultimately suspect for intestinal perforation, an intraoperative diagnosis of NOMI was made.

CONCLUSION

The diagnosis of DKA-associated NOMI must be suspected in pediatric patients with DKA, persistent abdominal pain, and severe dehydration even after DKA resolution.

Case Report: Off-Label Liraglutide Use in Children With Wolfram Syndrome Type 1: Extensive Characterization of Four Patients

Aims: Wolfram syndrome type 1 is a rare recessive monogenic form of insulin-dependent diabetes mellitus with progressive neurodegeneration, poor prognosis, and no cure. Based on preclinical evidence we hypothesized that liraglutide, a glucagon-like peptide-1 receptor agonist, may be repurposed for the off-label treatment of Wolfram Syndrome type 1. We initiated an off-label treatment to investigate the safety, tolerability, and efficacy of liraglutide in pediatric patients with Wolfram Syndrome type 1. Methods: Pediatric patients with genetically confirmed Wolfram Syndrome type 1 were offered off-label treatment approved by The Regional Network Coordination Center for Rare Diseases, Pharmacological Research IRCCS Mario Negri, and the internal ethics committee. Four patients were enrolled; none refused nor were excluded or lost during follow-up. Liraglutide was administered as a daily subcutaneous injection. Starting dose was 0.3 mg/day. The dose was progressively increased as tolerated, up to the maximum dose of 1.8 mg/day. The primary outcome was evaluating the safety, tolerability, and efficacy of liraglutide in Wolfram Syndrome type 1 patients. Secondary endpoints were stabilization or improvement of C-peptide secretion as assessed by the mixed meal tolerance test. Exploratory endpoints were stabilization of neurological and neuro-ophthalmological degeneration, assessed by optical coherence tomography, electroretinogram, visual evoked potentials, and magnetic resonance imaging. Results: Four patients aged between 10 and 14 years at baseline were treated with liraglutide for 8-27 months. Liraglutide was well-tolerated: all patients reached and maintained the maximum dose, and none withdrew from the study. Only minor transient gastrointestinal symptoms were reported. No alterations in pancreatic enzymes, calcitonin, or thyroid hormones were observed. At the latest follow-up, the C-peptide area under the curve ranged from 81 to 171% of baseline. Time in range improved in two patients. Neuro-ophthalmological and neurophysiological disease parameters remained stable at the latest follow-up. Conclusions: We report preliminary data on the safety, tolerability, and efficacy of liraglutide in four pediatric patients with Wolfram Syndrome type 1. The apparent benefits both in terms of residual C-peptide secretion and neuro-ophthalmological disease progression warrant further studies on the repurposing of glucagon-like peptide-1 receptor agonists as disease-modifying agents for Wolfram Syndrome type 1.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Necrobiosis Lipoidica Diabeticorum: A pediatric case report

Introduction: Necrobiosis lipoidica (NL) is a rare chronic granulomatous dermatitis that usually appears in the lower extremities. It affects about 0.3–1.2% of diabetic patients, the majority of whom have type 1 diabetes. The etiology and pathogenesis of this disorder are still unclear. NL is characterized by skin rash that usually affects the shins. The average onset is 30 years, with females being affected more commonly. There are very few reported cases of necrobiosis lipoidica in children.

Case report: We report a case of a 16 year old girl affected by type 1 diabetes mellitus (15 years disease duration) who developed an erythematous nodular rash on the lower extremities and interscapular area. In the suspect of necrobiosis lipoidica, a skin biopsy was performed (lower extremities and interscapular area). The microscopic evaluation of the pretibial lesions was suggestive of necrobiosis lipoidica. The smaller lesions in the interscapular area showed signs of perivascular dermatitis which could be consistent with early stages of necrobiosis lipoidica. Local treatment with tacrolimus determined a progressive improvement of the lesions.

Conclusion: In patients with T1DM, diagnosis of NL of the lower legs is usually unequivocal. However, diagnosis may be more challenging in the presence of lesions with recent onset and/or atypical clinical presentation and unusual site. In these cases, NL must always be taken in consideration in order to avoid misdiagnosis, wrong/late treatment decisions and progression to ulceration.

Six cases with severe insulin resistance (SIR) associated with mutations of insulin receptor: Is a Bartter-like syndrome a feature of congenital SIR?

Biallelic insulin receptor (INSR) gene mutations cause congenital syndromes of severe insulin resistance (SIR) known as Donohue syndrome (DS) and Rabson-Mendenhall syndrome (RMS). At presentation, DS and RMS are difficult to differentiate since they share many clinical features; however, while patients with DS usually die within 1 year of birth, individuals classified as RMS can reach adult age. INSR mutations can be also found in pubertal females with hyperinsulinism, hyperandrogenism, and acanthosis nigricans (type A SIR). We studied the INSR gene in five subjects with congenital SIR and in a patient with type A SIR. Nine biallelic INSR gene mutations (eight novels, including an in-frame deletion of INSR signal peptide) were identified in patients with congenital SIR; a heterozygous, spontaneous INSR mutation was detected in the patient with type A SIR. Two probands, presenting severe hirsutism at birth, died at the age of 3 months and were classified as DS, while other 2, currently 2 and 3 years old, were diagnosed with RMS (patients 3 and 4). The fifth patient with congenital SIR died when 14 months old. Nephrocalcinosis, hyperaldosteronism, hyperreninemia, and hypokalemia, in the absence of hypertension, were discovered in patients 3 and 5 when 24 and 4 months old, respectively. Patient 3, now 3 years/3 months old, still shows hyperreninemic hyperaldosteronism requiring potassium supplementation. We conclude that renal abnormalities resembling antenatal Bartter's syndrome type II, recently reported also by others, is a common observation in patients with congenital SIR.

Reduction of circulating neutrophils precedes and accompanies type 1 diabetes

Human type 1 diabetes (T1D) is an autoimmune disease associated with major histocompatibility complex polymorphisms, β-cell autoantibodies, and autoreactive T cells. However, there is increasing evidence that innate cells may also play critical roles in T1D. We aimed to monitor peripheral immune cells in early stages of T1D (i.e., in healthy autoantibody-positive subjects) and in more advanced phases of the disease (i.e., at disease onset and years after diagnosis). We found a mild but significant and reproducible peripheral neutropenia that both precedes and accompanies the onset of T1D. This reduction was not due to peripheral neutrophil cell death, impaired differentiation, or the presence of anti-neutrophil antibodies. Neutrophils were observed by electron microscopy and immunohistochemical analysis in the exocrine pancreas of multiorgan donors with T1D (both at onset and at later stages of the disease) and not in that of multiorgan donors with type 2 diabetes or nondiabetic donors. These pancreas-infiltrating neutrophils mainly localized at the level of very small blood vessels. Our findings suggest the existence of a hitherto unrecognized clinical phenotype that might reflect unexplored pathogenic pathways underlying T1D.

Future Perspectives in Glucose Monitoring Sensors

The prevalence of diabetes is increasing. improved glucose control is fundamental to reduce both long-term micro- and macrovascular complications and short-term complications, such as diabetic ketoacidosis and severe hypoglycemia. Frequent blood glucose monitoring is an essential part of diabetes management. However, almost all available blood glucose monitoring devices are invasive. This determines a reduced patient compliance, which in turn reflects negatively on glucose control. Therefore, there is a need to develop noninvasive glucose monitoring devices that will reduce the need of invasive procedures, thus increasing patient compliance and consequently improving quality of life and health of patients with diabetes.

Future Perspectives in Glucose Monitoring Sensors

The prevalence of diabetes is increasing. Improved glucose control is fundamental to reduce both long-term micro- and macrovascular complications and short-term complications, such as diabetic ketoacidosis and severe hypoglycemia. Frequent blood glucose monitoring is an essential part of diabetes management. However, almost all available blood glucose monitoring devices are invasive. This determines a reduced patient compliance, which in turn reflects negatively on glucose control. Therefore, there is a need to develop noninvasive glucose monitoring devices that will reduce the need of invasive procedures, thus increasing patient compliance and consequently improving quality of life and health of patients with diabetes.

Minimal incidence of neonatal/infancy onset diabetes in Italy is 1:90,000 live births

Until early 2000, permanent and transient neonatal diabetes mellitus (NDM), defined as diabetes with onset within 6 weeks from birth that requires insulin therapy for at least 2 weeks, were considered exceedingly rare conditions, with a global incidence of 1:500,000-1:400,000 live births. The new definition of NDM recently adopted, that includes patients with diabetes onset within 6 months of age, has prompted studies that have set the incidence of the permanent form alone between 1:210,000 and 1:260,000 live births. Aim of the present work was to ascertain the incidence of NDM (i.e. permanent + transient form) in Italy for years 2005-2010. Patients referred to the Italian reference laboratory for NDM between years 2005 and 2010 and screened for mutations in common NDM genes (KCNJ11, ABCC8, and INS) and for uniparental isodisomy of chromosome 6 (UDP6) were reviewed. A questionnaire aimed at identifying NDM cases investigated in other laboratories was sent to 54 Italian reference centers for pediatric diabetes. Twenty-seven patients with NDM born between 2005 and 2010 were referred to the reference laboratory. In this group, a mutation of either KCNJ11, ABCC8 or INS was found in 18 patients, and a case with UDP6 was identified. Questionnaires revealed 4 additional cases with transient neonatal diabetes due to UDP6. Incidence of NDM was calculated at 1:90,000 (CI: 1:63,000-1:132,000) live births. Thus, with the definition currently in use, about 6 new cases with NDM are expected to be born in Italy each year.

Sensor-augmented pump therapy in very young children with type 1 diabetes: an efficacy and feasibility observational study

BACKGROUND

Efficacy and feasibility of sensor-augmented pump (SAP) therapy were evaluated in very young children with type 1 diabetes (T1D).

SUBJECTS AND METHODS

SAP (Dexcom [San Diego, CA] Seven Plus™ usage combined with insulin pump) therapy was retrospectively evaluated in 28 children (15 boys) younger than 7 years (mean age, 5.8 ± 1.2 years; range, 3-7 years), with T1D. Glycosylated hemoglobin (HbA1c) was evaluated at baseline and at the end of the study, as were efficacy and feasibility of the system, using a rating scale (with 3 being the most positive).

RESULTS

SAP has been used for at least 6 months by 85% of patients, with an overall good satisfaction (92%). The greatest perceived benefit was the reduced fear of hypoglycemia (score of 3, 81%). HbA1c significantly improved only in patients with baseline HbA1c >7.5% (P = 0.026).

CONCLUSIONS

SAP therapy is effective and feasible in preschool children with T1D. In patients with high HbA1c at baseline it provide a 0.9% decrease, sustained for at least 6 months.

Patients' evaluation of nocturnal hypoglycaemia with GlucoDay continuous glucose monitoring in paediatric patients

A study was conducted to evaluate the accuracy of GlucoDay (A. Menarini Diagnostics) during 48 h of continuous glucose monitoring (CGMS) in type 1 diabetic adolescents and use this novel approach to assess otherwise ignored nocturnal hypoglycaemias, in relationship to intermediate-acting insulin administration timing. Twenty type 1 diabetic adolescents with poor metabolic control were selected from our out-patient department. Equal doses of intermediate insulin were administered at 19:00 and at 22:00 of the first and second night of the study, respectively. Correlation coefficient between GlucoDay and standard glucometer was 0.94; 98.3% of data fall in the A + B area of Error Grid Analysis and 1.7% in the D area. The mean error was 13.9% overall and 16.4% with blood glucose values (BGV) <75 mg/dl. The accuracy, ±15 mg/dl, was 82% for BGV <75 mg/dl and 74% for BGV >75 mg/dl. The CGMS discovered nocturnal hypoglycaemia (NH) in 12/18 patients, but no severe hypoglycaemia. During the first night, 8 asymptomatic NH episodes were found with BGV <60 mg/dl and 12 with BGV <80. During the second night, 4 asymptomatic NH episodes with BGV <60 mg/dl and 5 with BGV <80 were found. Furthermore, during the second night, the mean duration of BGV <126 mg/dl was lower than in the first night. GlucoDay is a reliable device for CGMS in paediatric patients and able to determine asymptomatic NH. Bedtime insulin injections provided safer glycaemic profiles and a lower percentage of hypoglycaemic events, representing a safer insulin administration scheme.

Recommendations for the implementation of international standardization of glycated hemoglobin in Italy

This document is issued by the Italian Society of Clinical Biochemistry and Clinical Molecular Biology (SIBioC) and a number of other National Scientific Societies and Associations in order to promote a coordinated plan for implementing the standardization of glycated hemoglobin (HbA(1c)) measurement in Italy according to the recommendations by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC). Changes in reporting HbA(1c) results, new units, how to relate old and new units, a timeline for changes and definition of the analytical goals are the main issues discussed.

Maturity-onset diabetes of the young in children with incidental hyperglycemia: a multicenter Italian study of 172 families

OBJECTIVE

To investigate the prevalence of maturity-onset diabetes of the young (MODY) in Italian children with incidental hyperglycemia.

RESEARCH DESIGN AND METHODS

Among 748 subjects age 1-18 years with incidental hyperglycemia, minimal diagnostic criteria for MODY were met by 172 families. Mutational analyses of the glucokinase (GCK) and hepatocyte nuclear factor 1alpha (HNF1A) genes were performed.

RESULTS

We identified 85 GCK gene mutations in 109 probands and 10 HNF1A mutations in 12 probands. In GCK patients, the median neonatal weight and age at the first evaluation were lower than those found in patients with HNF1A mutations. Median fasting plasma glucose and impaired fasting glucose/impaired glucose tolerance frequency after oral glucose tolerance testing were higher in GCK patients, who also showed a lower frequency of diabetes than HNF1A patients.

CONCLUSIONS

GCK mutations are the prevailing cause of MODY (63.4%) when the index case is recruited in Italian children with incidental hyperglycemia.

Insulin gene mutations as cause of diabetes in children negative for five type 1 diabetes autoantibodies

OBJECTIVE

Heterozygous, gain-of-function mutations of the insulin gene can cause permanent diabetes with onset ranging from the neonatal period through adulthood. The aim of our study was to screen for the insulin gene in patients who had been clinically classified as type 1 diabetic but who tested negative for type 1 diabetes autoantibodies.

RESEARCH DESIGN AND METHODS

We reviewed the clinical records of 326 patients with the diagnosis of type 1 diabetes and identified seven probands who had diabetes in isolation and were negative for five type 1 diabetes autoantibodies. We sequenced the INS gene in these seven patients.

RESULTS

In two patients whose diabetes onset had been at 2 years 10 months of age and at 6 years 8 months of age, respectively, we identified the mutation G(B8)S and a novel mutation in the preproinsulin signal peptide (A(Signal23)S).

CONCLUSIONS

Insulin gene mutations are rare in absolute terms in patients classified as type 1 diabetic (0.6%) but can be identified after a thorough screening of type 1 diabetes autoantibodies.

Clinical and molecular profile of a new series of patients with immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome: inconsistent correlation between forkhead box protein 3 expression and disease severity

BACKGROUND

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an autoimmune genetic disorder caused by mutation of the forkhead box protein 3 gene (FOXP3), a key regulator of immune tolerance.

OBJECTIVE

We sought to provide clinical and molecular indicators that facilitate the understanding and diagnosis of IPEX syndrome.

METHODS

In 14 unrelated affected male subjects who were given diagnoses of IPEX syndrome based on FOXP3 gene sequencing, we determined whether particular FOXP3 mutations affected FOXP3 protein expression and correlated the molecular and clinical data.

RESULTS

Molecular analysis of FOXP3 in the 14 subjects revealed 13 missense and splice-site mutations, including 7 novel mutations. Enteropathy, generally associated with endocrinopathy and eczema, was reported in all patients, particularly in those carrying mutations within FOXP3 functional domains or mutations that altered protein expression. However, similar genotypes did not always result in similar phenotypes in terms of disease presentation and severity. In addition, FOXP3 protein expression did not correlate with disease severity.

CONCLUSION

Severe autoimmune enteropathy, which is often associated with increased IgE levels and eosinophilia, is the most prominent early manifestation of IPEX syndrome. Nevertheless, the disease course is variable and somewhat unpredictable. Therefore genetic analysis of FOXP3 should always be performed to ensure an accurate diagnosis, and FOXP3 protein expression analysis should not be the only diagnostic tool for IPEX syndrome.

Missense mutations in the TGM2 gene encoding transglutaminase 2 are found in patients with early-onset type 2 diabetes. Mutation in brief no. 982. Online

Transglutaminase 2 (TG2 or TGM2) is a multi-functional enzyme which catalyzes transamidation reactions or acts as a G-protein in intracellular signalling. Tgm2-/- Mice lacking TG2 activity are glucose intolerant and show impairment of insulin secretion, suggesting an important physiological role for TG2 in the pancreatic beta cell. We have previously described a TGM2 heterozygous missense mutation ((c.998A>G, p.N333S) in a 14 year-old patient with insulin-treated diabetes and in his diabetic father. The aim of this study was to further investigate the role of TG2 in early-onset type 2 diabetes. We analysed the TGM2 gene in 205 patients with clinically defined Maturity Onset Diabetes of the Young (MODY) or early-onset type 2 diabetes. We found two novel heterozygous mutations (c.989T>G, p.M330R; c.992T>A, p.I331N), which were not detected in 300 normoglycemic controls. All mutations were in residues which are located close to the catalytic site and impaired transamidating activity in vitro. Gene expression of TGM family genes and localization of TG2 in normal human pancreas indicated that TG2 is the only transglutaminase significantly expressed in human pancreatic islet cells. We conclude that reduced TG2 activity can contribute to disorders of glucose metabolism possibly via an impairment of insulin secretion.

Length of gestation and gender are associated with HLA genotypes at risk for Type 1 diabetes (Italian DIABFIN 3)

AIM

The aim of this study, which is part of the ongoing DIABFIN project, was to correlate HLA class II genotypes, classified for their effect on susceptibility to Type 1 diabetes (T1D), with various risk factors during pregnancy and the neonatal period.

METHODS

Cord blood was collected from 4349 neonates; 1.0% were at high HLA risk (HR), 9.0% at moderate HLA risk (MR), and 90.0% at low HLA risk (LR) for T1D. Information about the mother's pregnancy, type of delivery, the neonates' clinical features at birth, and family history for autoimmune diseases were collected.

RESULTS

Significant correlations were found between the different HLA risk categories and length of gestation, even when adjusted for sex, weight and length at birth of the neonate, birth order and mother's age (adjusted P = 0.007). The male : female ratio tended to increase from the LR to the HR category, from 1.00 and 1.21, respectively, in the LR and MR groups, to 1.62 in the HR group (P = 0.05).

CONCLUSIONS

Length of gestation is inversely correlated with HLA risk categories for T1D. The higher the HLA risk for T1D, the shorter the gestational age, especially in male neonates.

Persistent renal hypertrophy and faster decline of glomerular filtration rate precede the development of microalbuminuria in type 1 diabetes

Soon after the onset of type 1 diabetes, renal hypertrophy and hyperfiltration become manifest, particularly among patients who will subsequently develop diabetic nephropathy. Whether these early renal dysfunctions are involved in the pathogenesis of diabetic nephropathy is currently unclear. We evaluated, during the same day, kidney volume and glomerular filtration rate (GFR) in 146 patients with type 1 diabetes and normal renal function. All the individuals were then monitored for a mean of 9.5 +/- 4.4 years for the development of microalbuminuria. Kidney volume and GFR were reevaluated in a subset of 68 patients 4 years after baseline. During follow-up, microalbuminuria developed in 27 of 146 diabetic patients. At baseline, kidney volume (312.8 +/- 52.6 vs. 281.4 +/- 46.1 vs. 236.8 +/- 41.6 ml/1.73 m(2), P < 0.05) but not GFR was increased in patients predisposed to microalbuminuria. Risk of progression was higher in patients with increased kidney volume (P = 0.0058). Patients predisposed to microalbuminuria showed a stable increase in kidney volume (P = 0.003), along with a faster decline of GFR (P = 0.01). Persistent renal hypertrophy and faster decline of GFR precede the development of microalbuminuria in type 1 diabetes. These findings support the hypothesis that renal hypertrophy precedes hyperfiltration during the development of diabetic nephropathy.

KCNJ11 activating mutations in Italian patients with permanent neonatal diabetes

Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes.

Nationwide cross-sectional survey of 3560 children and adolescents with diabetes in Italy

Clinical characteristics and metabolic control in a large cohort of children with Type 1 diabetes (T1DM) were evaluated. Fifty-three Italian centers for childhood diabetes collected blood samples and clinical records from 3560 consecutive eligible patients aged 1.6-17.10 yr with disease duration >12 months. HbA1c determinations were centralized in a Diabetes Control and Complications Trial-controlled laboratory. HbA1c grand mean was 8.87 +/- 1.77%. Thirty-two percent of the patients had HbA1c values <8.0%. Puberty and disease duration were the main determinants of increase in HbA1c levels (<0.001). HbA1c values were inversely correlated to the frequency of blood glucose monitoring (p<0.001). Among the total population, 53.7% of the patients had 4 or more injections per day, 37.8% three injections, 7.4% < or =2 injections and only 1.1% was on pumps. Daily number of injections increased with age (p<0.001). Hypoglycemia episodes were reported in 17.6% patient-years and diabetic ketoacidosis (DKA) in 1.0% of children, more frequently in those with HbA1c >8.8% (p<0.02). Two thirds of Italian children with T1DM have HbA1c>8% despite regionalized centers, multidisciplinary team approach, free access to appropriate diabetes care, education, frequent blood glucose monitoring and multiple insulin injections.

Insulin therapy and carbohydrate counting

Nutritional management is one of the cornerstones of diabetes care. Many studies have been performed on the correlation between nature and amount of carbohydrate in meal intake and insulin delivery by artificial pancreas in Type 1 diabetic patients. In fact consistency in the amount and source of carbohydrate intake from day to day is associated with improved blood glucose control in people with Type 1 diabetes. Many methods of counting carbohydrate have been used and many are still commonly used in paediatric practice (exchange, portion/serving, grams, glycemic index, carbohydrate/insulin ratio). Carbohydrate counting is a meal planning approach with patients with Type 1 diabetes mellitus that focuses on carbohydrate as the primary nutrient affecting postprandial glycemic response. The aim of this paper is to review published data on the significance of carbohydrate counting on meeting outcome goals and allowing flexibility in food choices.

Younger age at onset and sex predict celiac disease in children and adolescents with type 1 diabetes: an Italian multicenter study

OBJECTIVE

To estimate the prevalence of biopsy-confirmed celiac disease in Italian children and adolescents with type 1 diabetes and to assess whether age at onset of type 1 diabetes is independently associated with diagnosis of celiac disease.

RESEARCH DESIGN AND METHODS

The study group was a clinic-based cohort of children and adolescents with type 1 diabetes cared for in 25 Italian centers for childhood diabetes. Yearly screening for celiac disease was performed using IgA/IgG anti-gliadin and IgA anti-endomysium antibodies.

RESULTS

Of the 4,322 children and adolescents (age 11.8 +/- 4.2 years) identified with type 1 diabetes, biopsy-confirmed celiac disease was diagnosed in 292 (prevalence 6.8%, 95% confidence interval [CI] 6.0-7.6), with a higher risk seen in girls than in boys (odds ratio [OR] 1.93, 1.51-2.47). In 89% of these, diabetes was diagnosed before celiac disease. In logistic regression analyses, being younger at onset of diabetes, being female, and having a diagnosis of a thyroid disorder were independently associated with the risk of having diabetes and celiac disease. In comparison with subjects who were older than 9 years at onset of diabetes, subjects who were younger than 4 years at onset had an OR of 3.27 (2.20-4.85).

CONCLUSIONS

We have provided evidence that 1) the prevalence of biopsy-confirmed celiac disease in children and adolescents with type 1 diabetes is high (6.8%); 2) the risk of having both diseases is threefold higher in children diagnosed with type 1 diabetes at age <4 years than in those age >9 years; and 3) girls have a higher risk of having both diseases than boys.

Genetic prediction of type 1 diabetes in a population with low frequency of HLA risk genotypes and low incidence of the disease (the DIABFIN study)

BACKGROUND

To develop a sensitive, specific screening strategy for predicting genetic risk for type 1 diabetes mellitus (T1DM) in the low-incidence continental Italian population, and to define with this tool, a cohort of high-to-moderate risk infants for an immunological follow-up study aimed at identifying environmental risk factors for T1DM.

METHODS

4855 newborns in three regions of continental Italy were screened for T1DM HLA-DRB1-DQB1 risk genotypes using a reverse line blot typing method. Risk classification was based on odds ratios (OR) found in a preliminary case-control study (356 T1DM patients, 412 controls). Screening efficiency was optimized by allele subtyping.

RESULTS

Screening for well-known T1DM susceptibility genotypes [DRB1*03/*04-DQB1*0302; DRB1*03/*03; DRB1*04/*04-DQB1*0302; DRB1*04-DQB1*0302/X where X is not equal to DRB1*03, DRB1*04-DQB1*0302, DQB1*0602 or DQB1*0603] was associated with <60% sensitivity due to their low frequencies in the general Italian population. Inclusion of an additional genotype from which protective DRB1 and DQB1 alleles had been excluded [DRB1*03/X degrees where DQB1 is not equal to *0301, *0503, *0602, or *0603 and X degrees not equal DRB1*03, DRB1*04-DQB1*0302 or DRB1*07] increased screening sensitivity to 75% (specificity: 85%). Among 4855 newborns, we have found the high-risk genotype [DRB1*03/*04-DQB1*0302; estimated absolute risk (AR) 1/23] to be present in only 0.9%. The moderate-risk genotypes were found in 13.8% of newborns (estimated AR 1/177).

CONCLUSIONS

Risk classification must be tailored to the characteristics of the individual population, in particular, the allelic frequencies in the background population and T1DM prevalence. We have developed a screening strategy with good levels of sensitivity that should prove effective for use throughout the Italian peninsula.

Quality of life and new devices in the management of type 1 diabetes in children and adolescents

Insulin therapy is the cornerstone in treatment of type 1 diabetes in children and adolescents. In order to prevent long-term complication multiple daily injections (MDI) are required. Quality of life is dearly affected by the administrations of 3-4 daily injections with syringe. Insulin pens are new devices realized with the aim of simplifying insulin administration. More recently continuous blood sugar monitoring has become available for clinical studies and its role for better metabolic control and quality of life is now under investigation. The aim of this paper is to review published data on the significance of insulin pen and continuous blood sugar monitoring on quality of life in diabetic children and adolescents.

Occurrence of celiac disease after onset of type 1 diabetes: a 6-year prospective longitudinal study

OBJECTIVE

To investigate the prevalence of celiac disease in a large cohort of children and adolescents at the onset of type 1 diabetes and the occurrence of new cases during a 6-year follow-up.

METHODS

We prospectively studied, by repeated serologic screening, 274 consecutive patients at the onset of type 1 diabetes (age [mean +/- standard deviation]: 8.28 +/- 4.65 years) for 6 subsequent years. One patient had a diagnosis of celiac disease before the onset of diabetes. The immunoglobulin A-antiendomysium antibody test was selected as the screening test; patients with positive results (++ or +++) or with 2 consecutive weak positive tests (+) were considered appropriate for the jejunal biopsy.

RESULTS

At diabetes onset, 15 (5.5%) of 273 patients tested positive with the antiendomysium test; jejunal biopsy was performed in 10, and celiac disease was diagnosed in 9. The prevalence of biopsy-confirmed celiac disease at the manifestation of diabetes was 3.6% (10 of 274 patients). Twelve more patients with a negative antiendomysium antibody test at diabetes onset tested positive during the follow-up within 4 years; 10 of them had biopsies performed, and 7 had celiac disease. Therefore, the overall prevalence of biopsy-confirmed celiac disease in the entire cohort of patients was 6.2%. The age at diabetes onset in patients with and without celiac disease was not different (7.88 +/- 5.69 vs 8.3 +/- 4.58 years). The majority of cases of celiac disease were asymptomatic in their presentation, and no signs of overt malnutrition were documented.

CONCLUSIONS

The prevalence of celiac disease in patients with type 1 diabetes is approximately 20 times higher than in the general population. Sixty percent of cases are already present at diabetes onset, mostly undetected, but an additional 40% of patients develop celiac disease a few years after diabetes onset. Extending screening programs for celiac disease after the onset of type 1 diabetes is recommended, even in the absence of clinical symptoms.

High prevalence of glucokinase mutations in Italian children with MODY. Influence on glucose tolerance, first-phase insulin response, insulin sensitivity and BMI

AIMS/HYPOTHESIS

The aim of this study was to assess the prevalence of glucokinase gene mutations in Italian children with MODY and to investigate genotype/phenotype correlations of the mutants.

METHODS

Screening for sequence variants in the glucokinase gene was performed by denaturing gradient gel electrophoresis and direct sequencing in 132 children with maturity onset diabetes of the young (MODY) and in 9 children with chronic fasting hyperglycaemia but without laboratory evidence for Type I (insulin-dependent) diabetes mellitus and with normoglycaemic parents ("non-classical" MODY).

RESULTS

Altogether 54 mutations were identified in the MODY group (54/132 or 41%) and 3 among the "non-classical" MODY individuals (3/9 or 33%). Paternity testing indicated that the latter mutations have arisen de novo. Mean fasting plasma glucose concentrations of the children with the mutant glucokinase was in the expected impaired fasting glucose range. In contrast, results of the oral glucose tolerance test showed a wide range from normal glucose tolerance (Group 1: 2-h OGTT = 6.7 +/- 1.1 mmol/l; 11 patients) to diabetes (Group 2: 2-h OGTT = 11.5 +/- 0.5 mmol/l; 9 patients), with the remaining in the impaired glucose tolerance range. Disruptive mutations (i.e. nonsense, frameshifts, splice-site) were equally represented in Groups 1 and 2 and were not clearly associated with an impaired first-phase insulin response. Surprisingly, 5 out of 11 children (or 45%) in Group 1 were found to be overweight but no children in Group 2 were overweight. Sensitivity index (SI), calculated by a recently described method, was found to be significantly lower in Group 2 than in Group 1 (SI Group 2 = 0.0013 +/- 0.0009 ml Kg(-1) min(-1)/muU/ml; SI Group 1 = 0.0068 +/- 0.0048, p < 0.0035).

CONCLUSION/INTERPRETATION

Mutations in glucokinase are the first cause of MODY among Italian children selected through a low threshold limit of fasting plasma glucose (i. e. > 5.5 mmol). The lack of correlation between the molecular severity of glucokinase mutations, insulin secretion at intravenous glucose tolerance test and differences in glucose tolerance suggests that factors outside the beta cell are also involved in determining post-load glucose concentrations in these subjects. Our results seem to indicate that the differences observed in the 2-h responses at the OGTT among children with MODY 2 could be related to individual differences in insulin sensitivity.

T cell responses to type 1 diabetes related peptides sharing homologous regions

Glutamic acid decarboxylase (GAD) 65 is a major autoantigen in type 1 diabetes. Regions of homology exist between GAD65 (residues 250-273) and the Coxsackie P2-C protein (residues 28-50) and between GAD65 (residues 506-518) and proinsulin (residues 24-36), and each of these has been reported to be a diabetes-associated T cell target. The aim of this study was to determine whether the homologous regions are shared targets of T lymphocyte reactivity in individual patients with type 1 diabetes. T cell proliferation against the corresponding peptide pairs, GAD254-276 and Coxsackie P2-C32-54 and GAD506-518 and proinsulin24-36, were measured in peripheral blood mononuclear cells from 26 patients with newly diagnosed type 1 diabetes and 24 control subjects. Responses with stimulation indices higher than 3 were found against each of the antigens tested in both patients and control subjects, and no differences were observed between groups. A strong positive correlation was found between responses to the corresponding peptide pairs GAD254-276 and Coxsackie P2-C32-54 (r=0.77, P<0.0001), and between responses to the corresponding peptide pairs GAD506-518 and proinsulin24-36 (r=0.66, P<0.0001). However, a similar correlation was also observed between responses to the noncorresponding pairs Coxsackie P2-C32-54 and proinsulin24-36 (r=0.82, P<0.0001), Coxsackie P2-C32-54 and GAD506-518 (r=0.82, P<0.0001), and GAD254-276 and proinsulin24-36 (r=0.83, P<0.0001). Strikingly, increased responses to peptides were found almost exclusively in subjects with high stimulation indices against the recall antigen tetanus toxoid, further suggesting that peripheral blood T cell responses are related to a general subject hyperreactivity. These data suggest that proliferative T cell responses to peptides containing putative autoreactive epitopes of GAD65 and proinsulin are not specific for type 1 diabetes, that correlation between T cell reactivity to peptides is not restricted to those containing homologous regions, and that non-antigen-specific factors are important determinants of in vitro measurements of T cell reactivity.

Three novel missense mutations in the glucokinase gene (G80S; E221K; G227C) in Italian subjects with maturity-onset diabetes of the young (MODY). Mutations in brief no. 162. Online

The maturity-onset diabetes of the young (MODY), an autosomal dominant form of non-insulin dependent diabetes mellitus (NIDDM), is caused by mutations in the glucokinase (GK, MODY 2) and in the hepatocyte nuclear factor 1a (MODY 3) and 4a (MODY 1) genes. We have screened the glucokinase gene by the polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE) in fifteen subjects with clinical characteristics of MODY and one parent with NIDDM, impaired glucose tolerance or gestational diabetes. PCR products with abnormal mobility in DGGE were directly sequenced. We have identified four mutant alleles, three of them (G80S, E221K, G227C) are new missense mutations located in or near the region of the active site cleft of the enzyme. The mutations co-segregate with hyperglycemia in the families of the three probands, whose biochemical and clinical phenotype is similar to other individuals with MODY 2 mutations.

Cellular and humoral immunity against cow's milk proteins in type 1 diabetes

Cow's milk beta-casein has been proposed as a candidate trigger of autoimmunity associated with type 1 diabetes. In this study, cellular and humoral immunity against beta-casein was compared to that against other major cow's milk proteins in patients with recent onset type 1 diabetes and control subjects. T cell responses were found against alpha-casein, beta-casein, beta-lactoglobulin and bovine serum albumin in both patients with type 1 diabetes (stimulation index: 0.2-22.8, n=23) and control subjects (stimulation index: 0.1-18.2, n=22), with no significant differences between groups. Twelve (52%) patients and nine (41%) control subjects had stimulation indices >3 to at least one protein, including 9 (39%) patients and 4 (18%) control subjects against beta-casein, all but one of these also having elevated responses to alpha-casein. The highest responses (stimulation index >9) were against alpha- and beta-casein in some patients and control subjects who had the HLA DR3 allele. Antibody levels against alpha-casein, beta-casein and beta-lactoglobulin were low in both patients (n=59) and control subjects (n=52). Nevertheless, significantly higher IgG binding to both alpha-casein in ELISA (P=0.02) and beta-casein using ELISA (P=0.02) and RIA (P=0.04) was observed in patients aged <15 years compared to control subjects of similar age. No relationship was found between cellular and humoral immunity against individual antigens. These data show that immune responses to cow's milk are not limited to patients with diabetes and not solely against beta-casein.

Myoclonic encephalopathy and diabetes mellitus in a boy

We describe an 18-month-old boy with insulin-dependent diabetes mellitus who developed idiopathic myoclonic encephalopathy (dancing eye syndrome) at 26 months of age. The neurological symptomatology (multifocal myoclonus, opsoclonus, ataxia, behavioural disturbance) developed within 10 to 14 days after presentation. Biological, neuroradiological, and scintigraphic examination excluded CNS infectious diseases, intoxication, or tumours. At onset of diabetes mellitus, anti-glutamic-acid decarboxylase (GAD) antibodies were observed, and markedly increased in titre when myoclonic encephalopathy occurred. Corticosteroid treatment resulted in a decrease in anti-GAD autoantibody titres and the disappearance of neurological disturbances. As GAD is expressed both in pancreatic beta-cells and cerebellar Purkinje cells, it is possible that a common autoimmune disorder in this patient may account for both the diabetes and myoclonic encephalopathy.

Autoimmune responses to the beta cell autoantigen, insulin, and the INS VNTR-IDDM2 locus

Type 1 diabetes is associated with autoimmunity to insulin. Genetic susceptibility to type 1 diabetes is polygenic and includes the INS VNTR-IDDM2 locus which may regulate the expression of insulin in pancreas and thymus. In order to determine whether insulin autoimmunity could be attributed to a genetic susceptibility conferred by the INS VNTR-IDDM2 locus, peripheral blood T cell proliferation to human insulin and insulin autoantibodies (IAA) was measured in patients with new onset type 1 diabetes and control subjects. IAA were detected in 21 of 53 patients and in none of 25 control subjects, while T cell responses were low (stimulation index range 0.4-7.2) and similar in both groups. Both antibody and T cell responses were higher in younger subjects and IAA were more prevalent in patients with the HLA-DR4 allele. No relationship was observed between humoral and cellular responses to insulin. No association was found between the INS VNTR-IDDM2-susceptible allele and insulin autoimmunity. Increased T cell responses and IAA were found in patients with either the diabetes-susceptible or the diabetes-protective INS VNTR-IDDM2 locus genotypes, and increased T cell responses were also found in control subjects with either susceptible or protective INS VNTR-IDDM2 locus genotypes. This study confirms that primary T cell proliferative responses to insulin are low and detectable also in control subjects. The detection of T cell proliferation and autoantibodies to insulin in subjects with and without the protective INS VNTR-IDDM2 locus genotypes does not support the hypothesis of an allele-specific capacity for tolerance induction which could determine a susceptibility to develop autoimmunity against the insulin protein and subsequently diabetes.

Parameters associated with residual insulin secretion during the first year of disease in children and adolescents with Type 1 diabetes mellitus

Factors associated with residual insulin secretion and spontaneous remission in Type 1 diabetic patients are important in the evaluation of treatment aimed at modifying the natural history of Type 1 DM. We investigated the effect of parameters at onset on residual beta cell function in 215 Type 1 DM children and adolescents. Blood gas analysis, HLA, GAD and IA-2 antibodies before the start of insulin treatment were recorded for each patient. Residual C-peptide secretion was assessed by the glucagon test, and parameters of metabolic control (HbA1c and insulin dose U kg(-1) day(-1)) were examined at disease onset and after 3, 6, and 12 months. Residual C-peptide secretion throughout the first year of disease was significantly reduced in patients with disease onset before age 5. Multiple regression analysis showed that low pH at onset showed a significant and independent association with reduced C-peptide at 3 months (p = 0.02) and that the detection of GAD antibodies had a significant independent association with decreased C-peptide secretion at 6 months of follow-up (p = 0.02). Insulin requirement was higher in the youngest patients group and in patients with GAD antibodies. Spontaneous insulin remission (HbA1c <6% and insulin <0.3 U kg(-1) day(-1)) occurred in 22/192 (11%) patients at 3 months of follow-up, in 15/190 (8%) patients at 6 months and in 8/169 (5%) patient at 12 months. Remission was more prevalent in older patients (p = 0.01) and in patients without detectable GAD antibodies: (14/64 vs 8/128, p = 0.001). Sex, IA-2 antibodies and HLA DR were not independently associated with C-peptide secretion, insulin requirement or remission in the first year of Type 1 DM. This study confirms the association of young age, severe acidosis at disease onset, and GAD antibodies with decreased residual beta-cell function and spontaneous remission during the first year of insulin treatment. These factors should be considered in trials evaluating therapies to retain beta-cell function and induce remission at and after disease onset.

Two-step islet autoantibody screening for risk assessment of type 1 diabetes in relatives

OBJECTIVE

To examine the performance of islet cell antibodies (ICAs) and antibodies to glutamate decarboxylase (GADA), IA-2 (IA-2 antibody [IA-2A]), and insulin (insulin autoantibody [IAA]), alone and in combination, in assessing type 1 diabetes risk within type 1 diabetic families to identify a practical and effective screening strategy for predicting type 1 diabetes in relatives.

RESEARCH DESIGN AND METHODS

ICA, GADA, IA-2A, and IAA were determined in 806 first-degree relatives participating in a prospective type 1 diabetes family study (median follow-up 6.17 years, range 0.6-8.3). The conferred risk of developing type 1 diabetes within 6 years was evaluated by Kaplan-Meier for each antibody marker, used alone or in combination.

RESULTS

ICAs were detected in 3%, GADA in 5.1%, IA-2A in 2.5%, and IAA in 3.7% of relatives; > or =1 antibody markers were detected in 10.7% of relatives and > or =2 were detected in 1.9% of relatives. The risk of type 1 diabetes at 6 years was 1.5% in relatives with only 1 marker and 24.8% in relatives with > or =2 markers. As a practical and effective strategy for type 1 diabetes risk assessment in relatives, this study indicates a first-step screening based on GADA and IA-2A measurement--which identified 6.5% of relatives, including all who developed the disease, with a 6-year type 1 diabetes risk of 9.0%--followed by a second step based on ICA and IAA measurement in relatives with either GADA or IA-2A, which identified a total of 1.9% of all relatives as having > or =2 markers, and a 6-year risk of 24.8%, including 6 of 7 who developed type 1 diabetes.

CONCLUSIONS

A two-step antibody screening, based first on GADA and IA-2A and then on ICA and IAA measurements in identified individuals, is likely to be a practical, sensitive, and effective strategy for predicting type 1 diabetes in first-degree relatives.

Growth changes in children and adolescents with short-term diabetes

OBJECTIVE

Height and weight changes during the first 3 years of diabetes were prospectively followed in 152 diabetic children and adolescents.

RESEARCH DESIGN AND METHODS

The study sample consisted of 152 Caucasian diabetic patients (84 boys; 68 girls) followed from diabetes onset in the Paediatric Diabetes Unit and 80 Caucasian normal subjects (49 boys; 31 girls) assessed in the Outpatient General Paediatric Clinic of the same hospital for routine examination and not affected by problems that might influence growth. Diabetic patients and control subjects were consecutively enrolled in the study between 1989 and 1992; diabetic patients with positive markers for celiac disease (positive antiendomysial antibodies) and thyroid disease (positive antimicrosomial antibodies) or any other chronic disease were not considered in the study. Mean age of diabetic patients (8.9 +/- 4.1 years) and control subjects (8.5 +/- 4.2 years) at recruitment in the study was similar.

RESULTS

At onset of diabetes, the mean height expressed as the height standard deviation score (HSDS) was significantly greater than the expected values (P < 0.0001) and was independent of sex and pubertal stage. During the first 3 years of diabetes, HSDS decreased significantly (F = 6.9; P < 0.001). Meanwhile, growth velocity as standard deviation score (SDS) decreased significantly between the 1st and 2nd year (-0.12 +/- 2.1; -0.76 +/- 2.6, respectively; P < 0.05), but it was similar between the 2nd and 3rd year of diabetes. Weight expressed as SDS increased significantly during the first 2 years of diabetes but not thereafter. Height changes during the study period were independent from pubertal stage and sex. Metabolic control and insulin requirement, in our series, were not clearly related to height and weight changes.

CONCLUSIONS

Diabetic patients at onset of diabetes are taller than age- and sex-matched nondiabetic subjects. During the first years of the disease, linear growth decreases independently of metabolic control and weight changes.

Residual beta-cell function and spontaneous clinical remission in type 1 diabetes mellitus: the role of puberty

To investigate the role of puberty on spontaneous clinical remission and on secretion of residual C-peptide during the first year of type 1 diabetes mellitus, we studied 77 pre-pubertal, 39 pubertal and 41 post-pubertal type 1 diabetic patients. Spontaneous partial clinical remission (HbA1c within the normal range and insulin dose less than 0.3 U x kg(-1) body weight x day(-1) lasting for at least 10 days) decreased with duration of diabetes: months 3 vs 6 vs 12, respectively 13 vs 7 vs 4% (P<0.025). Remission was higher in post-pubertal than pubertal and prepubertal patients: month 6 respectively 20 vs 5 vs 1% (P<0.001). Secretion of C-peptide was significantly lower in pre-pubertal than the other two groups of patients. Basal and stimulated C-peptide secretion were higher in patients in clinical remission than in those who were not: basal value 0.4 (0.26-0.53) vs 0.28 (0.14-0.4) nmol/l (P<0.05); stimulated value 0.63 (0.5-0.95) vs 0.56 (0.31-0.74) nmol/l (P<0.05). Spontaneous remission is less frequent in children and adolescent patients than in adult post-pubertal patients, but different mechanisms may be involved. Low residual insulin secretion seems implicated in children meanwhile low insulin sensitivity could be more important in pubertal patients.

Prevalence and correlations of early microvascular complications in young type I diabetic patients: role of puberty

The prevalence and correlates of the early signs of renal, retinal and neurological microvascular complications were evaluated in 317 young patients with type I diabetes mellitus. Microalbuminuria was detected in 11% of patients and appeared to be strongly and positively related to HbA1c (p < 0.01) and less significantly to duration of diabetes (p < 0.02). Retinopathy was detected in 22.7% of patients and it was associated with duration of diabetes (p < 0.001). Peripheral neuropathy was detected in 18.5% of patients and there was a strong association with HbA1c (p < 0.01) and a weaker one with duration of diabetes (p < 0.05). Microalbuminuria was not detected in prepubertal patients while a similar frequency of retinopathy and neuropathy was observed in prepubertal and postpubertal patients. These results suggest that: 1) In short-term type I diabetic patients neuropathy is the most frequent microvascular complication, but after 10 years of diabetes, retinopathy exceeds the other complications; 2) Short-term metabolic control may influence the frequency of neuropathy and microalbuminuria but not retinopathy; 3) Puberty is involved in the appearance of microalbuminuria.

Frequency and correlates of severe hypoglycaemia in children and adolescents with diabetes mellitus

Frequency and correlates of severe hypoglycaemia have been retrospectively analysed in a cohort of diabetic children and adolescents with median (range) age 14.5 (3.2-25.5) years followed from the onset of the disease by the same diabetic clinic. During the years 1992-1994, 53 of the 187 patients reported 74 hypoglycaemic episodes: the average frequency of hypoglycaemia during the 3 years surveyed was 14.9 episodes/ 100 patients per year. Frequency of hypoglycaemia decreased significantly with age (chi 2 = 24.1; P < 0.0001) and was independent of duration of diabetes. Glycosylated haemoglobin and insulin dose were similar in patients with and without hypoglycaemia, matched for age and duration of diabetes. One out of two hypoglycaemic episodes occurred during sleep and no explanation was available for 50% of episodes.

CONCLUSION

In this study severe hypoglycaemia was more frequent in young children than in adolescents and was independent of metabolic control and insulin dose.