Pathogenesis of murine gammaherpesvirus infection in mice deficient in CD4 and CD8 T cells

Murine gammaherpesvirus is a natural pathogen of wild mice. The virus infects alveolar cells and spleen cells during the primary infection and establishes a latent/persistent infection in B lymphocytes. Little is known about the immunological response to gammaherpesviruses during a primary infection. To address this issue, we investigated the pathogenesis of murine herpesvirus 68 (MHV-68) infection in mice deficient in CD4 or CD8 T-cell populations. Infection of the lung and spleen were greatly exacerbated in CD8-deficient mice, reflected by elevated virus titers in the lung and an increase in the number of infected splenocytes located around germinal centers. This finding contrasts with clearance of virus from the lung and spleen by day 12 postinfection in CD4-depleted animals. These data clearly indicate a major role for CD8 T cells in recovery from an acute MHV-68 infection. Whereas CD4 T cells fail to influence the course of infection in the lung, they do contribute to lymphoproliferation seen in the spleen (splenomegaly) during the primary infection. The significance of these results are discussed in relation to the immune response to other herpesviruses, in particular Epstein-Barr virus, with which MHV-68 shares similar molecular and biological properties.

Type 2 diabetes mellitus in UK children--an emerging problem

AIMS

Type 2 diabetes mellitus has never previously been described in UK children, although an increasing incidence in childhood is recognized in international studies. The prevalence of obesity in UK children is increasing and is a recognized risk factor for the development of diabetes. The aim of this study was to identify and characterize children with Type 2 diabetes in the West Midlands and Leicester.

METHODS

Children were identified by contacting paediatricians responsible for diabetes in five hospitals. Details were collected on demographics, mode of presentation, investigations and treatment on a standard proforma.

RESULTS

Eight girls were identified with Type 2 diabetes, aged 9-16 years and who were of Pakistani, Indian or Arabic origin. They were all overweight (percentage weight for height 141-209%) and had a family history of diabetes in at least two generations. They presented insidiously with hyperglycaemia and glycosuria without ketosis and five were asymptomatic. Islet cell antibodies measured in seven patients were negative. Four had acanthosis nigricans which is a cutaneous marker of insulin resistance and the other four had high plasma levels of insulin and/or C peptide. These patients are distinct from those with maturity-onset diabetes of the young (MODY). All were initially managed with dietary measures, seven have been treated with oral anti-diabetic agents of whom two have subsequently required insulin.

CONCLUSIONS

These are the first UK case reports of Type 2 diabetes in children. Paediatricians need to be aware of the risk of Type 2 diabetes developing in childhood in high-risk ethnic groups, particularly in association with obesity and a positive family history.

First UK survey of paediatric type 2 diabetes and MODY

AIMS

To estimate the UK prevalence of childhood type 2 diabetes and maturity onset diabetes of the young (MODY), and distinguish them from each other and from type 1 diabetes.

METHODS

The British Society for Paediatric Endocrinology and Diabetes Clinical Trials/Audit Group undertook a cross-sectional questionnaire survey of all paediatric diabetes centres during 2000, collecting data on all children with non-type 1 diabetes.

RESULTS

Of 112 children reported to the survey, 25 had type 2 diabetes and 20 had MODY. In contrast to type 1, type 2 patients presented later (12.8 v 9.3 years), were usually female, overweight, or obese (92% v 28%), and a greater proportion were of ethnic minority origin (56% v 22%). In contrast to type 2, MODY patients were younger (10.8 years), less likely to be overweight or obese (50% v 92%), and none were from ethnic minority groups. The crude minimum UK prevalence of type 2 diabetes under 16 years is 0.21/100 000, and of MODY is 0.17/100 000. South Asian children have a relative risk of type 2 diabetes of 13.7 compared to white UK children.

CONCLUSIONS

UK children still have a low prevalence of type 2 diabetes. Children from ethnic minorities are at significantly higher risk, but in white UK children with non-type 1 diabetes a diagnosis of MODY is as likely as type 2 diabetes. Childhood type 2 diabetes is characterised by insulin resistance, and is distinct from both type 1 and MODY.

Ethnic differences in insulin resistance and body composition in United Kingdom adolescents

CONTEXT

Type 2 diabetes is increasingly recognized in childhood, occurring more frequently in the United Kingdom in South Asians and in girls. South Asian children have been shown to be more insulin resistant than white European children, and girls more insulin resistant than boys. It is not clear how these sex and ethnic differences relate to body composition in childhood.

OBJECTIVE

The goal was to evaluate sex and ethnic differences in insulin sensitivity and body composition in healthy adolescents.

DESIGN

This was a cross-sectional cohort study.

SETTING

This was a community-based study.

PARTICIPANTS

One hundred twenty-nine healthy white European and South Asian 14- to 17-yr-old adolescents participated.

INTERVENTIONS

Body composition was assessed by anthropometry and dual-energy x-ray absorptiometry, and insulin sensitivity by homeostasis model assessment.

MAIN OUTCOME MEASURES

The main outcome measures were body fat percentage and insulin sensitivity.

RESULTS

We confirmed that South Asian adolescents were less insulin sensitive than white European adolescents (homeostasis model assessment of insulin sensitivity, 52.4 vs. 58.9%, P < 0.05), with a trend toward lower insulin sensitivity in girls. South Asian adolescents had significantly more body fat than white European adolescents (girls, 30.6 vs. 26.0%, P < 0.005; boys, 20.8 vs. 14.8%, P < 0.001), with more central fat (waist-thigh ratio in girls, 1.36 vs. 1.25, P < 0.001; boys, 1.52 vs. 1.42, P < 0.001). The sex-ethnic differences in insulin sensitivity were no longer seen when body fat was included as a covariate.

CONCLUSIONS

Ethnic differences in insulin sensitivity are associated with ethnic differences in body fat. South Asian adolescents are more insulin resistant, with more body fat than white European adolescents, which may contribute to their increased risk of developing type 2 diabetes.

Persistent Müllerian duct syndrome: lessons learned from managing a series of eight patients over a 10-year period and review of literature regarding malignant risk from the Müllerian remnants

Study Type--Therapy (case series) Level of Evidence 4. What's known on the subject? and What does the study add? Approximately 200 cases of persistent Müllerian duct syndrome have been reported over the last 50 years and most authors suggest leaving the Müllerian remnant in situ because of the difficulty in dissection and the presumed absence of risk of malignancy. However, with increasing reports of Müllerian malignancies emerging, we report our 10-year experience of managing patients with persistent Müllerian duct syndrome, with removal of müllerian remnants. This case series shows that there is an increased risk of Müllerian malignancy that was previously unknown. With the laparoscopic approach, orchidopexy with simultaneous removal of Müllerian remnants could be accomplished with minimal surgical trauma and the benefit of no malignancy risk in the future. This is a new technique that has not been previously performed. Considering the current evidence of malignancy in the Müllerian remnant, surgeons would need to discuss with families about removal of remnants or long-term monitoring.

OBJECTIVES

• To describe the presentation and management of eight patients with persistent Müllerian duct syndrome (PMDS) seen over a 10-year period at our tertiary centre. • To review the literature of Müllerian malignancies reported in PMDS.

PATIENTS AND METHODS

• The hospital records of eight patients with PMDS were retrospectively reviewed between 2001 and 2011. • Extensive PubMed searches for PMDS and Müllerian malignancy were performed.

RESULTS

• Eleven cases with PMDS and malignancy of the Müllerian remnants were identified. • From our own PMDS series: five males presented with bilateral undescended testes and three had unilateral undescended testis. • We found that the Müllerian remnants could be removed by laparoscopy and three patients had simultaneous laparoscopic removal of the Müllerian structures and laparoscopic orchidopexy.

CONCLUSIONS

• The principle aim of orchidopexy with simultaneous laparoscopic removal of the Müllerian structures can be accomplished with minimal surgical trauma and the benefit of no malignancy risk in the future. • Surgeons should consider excision of the Müllerian remnants where possible.

Abnormal Neurodevelopmental Outcomes are Common in Children with Transient Congenital Hyperinsulinism

INTRODUCTION

Neuroglycopenia is recognized to be associated with abnormal neurodevelopmental outcomes in 26-44% of children with persistent congenital hyperinsulinism (P-CHI). The prevalence of abnormal neurodevelopment in transient CHI (T-CHI) is not known. We have aimed to investigate abnormal neurodevelopment and associated factors in T-CHI and P-CHI.

MATERIALS AND METHODS

A cohort of children with CHI (n = 67, age 2.5-5 years) was assessed at follow-up review and noted to have normal or abnormal (mild or severe) neurodevelopmental outcomes for the domains of speech and language, motor, and vision. Children were classified as P-CHI (n = 33), if they had undergone surgery or remained on medical therapy, or T-CHI (n = 34), if medical treatment for hypoglycemia was stopped.

RESULTS

Overall, abnormal neurodevelopment was present in 26 (39%) children with CHI, of whom 18 (69%) were severe. Importantly, the incidence of abnormal neurodevelopment in T-CHI was similar to that in P-CHI (30 vs. 47% respectively, p = 0.16). The prevalence of severe abnormal neurodevelopment in speech, motor, and vision domains was similar in both T-CHI and P-CHI children. For this cohort, we found that the severity of disease [based upon maximal diazoxide dose (odds ratio 95% confidence intervals) 1.3 (1.1; 1.5), p = 0.03], and early presentation of CHI <7 days following birth [5.9 (1.3; 27.8), p = 0.02] were significantly associated with abnormal neurodevelopment. There was no significant association with gender, genotype, or the histopathological basis of CHI.

CONCLUSION

Abnormal neurodevelopment was evident in one third of children with both T-CHI and P-CHI, early presentation and severe CHI being risk factors. Early recognition and rapid correction of hypoglycemia are advocated to avoid abnormal neurodevelopment in children with CHI.

Syndromic obesity and diabetes: changes in body composition with age and mutation analysis of ALMS1 in 12 United Kingdom kindreds with Alstrom syndrome

CONTEXT

Alström syndrome (AS) is a monogenic form of infancy-onset obesity and insulin resistance, caused by ALMS1 mutations. The natural history of the insulin resistance is unknown, in particular how this relates to changes in body composition. It is also unclear how ALMS1 mutations relate to the characteristic phenotype.

OBJECTIVES

Our objectives were to characterize body composition and metabolic parameters, to establish ALMS1 mutation spectrum of United Kingdom AS patients, and to determine whether a genotype-phenotype correlation exists.

DESIGN AND PATIENTS

We conducted a cross-sectional cohort study of 12 unrelated subjects with AS. Age-standardized body composition was assessed by anthropometry and dual-energy x-ray absorptiometry and insulin sensitivity by homeostasis model assessment. The exons and intron-exon boundaries of ALMS1 were directly sequenced.

SETTING

The study was performed during the annual Alström Syndrome UK multidisciplinary screening clinic.

RESULTS

AS patients have early-onset obesity, but body mass index, waist circumference, and body fat from dual-energy x-ray absorptiometry were negatively correlated with age (r = -0.37, P = 0.2; r = -0.84, P = 0.002; and r = -0.6, P = 0.05). Despite this, insulin resistance increased, demonstrated by raised fasting insulin and fall in homeostasis model assessment insulin sensitivity with age (r = -0.64, P = 0.02). ALMS1 mutations were identified in 10 of 12 patients, with a potential founder mutation in exon 16 present in five [np 10775del (C); Del3592fs/ter3597]. No genotype-phenotype correlation was observed.

CONCLUSIONS

We identified mutations in ALMS1 in more than 80% of patients with no genotype-phenotype correlation. In AS, severe childhood obesity, waist circumference, and body fat decrease with age, whereas insulin resistance increases. The abdominal obesity, insulin resistance, diabetes, hypertriglyceridemia, and hypertension suggest that AS could represent a monogenic model for the metabolic syndrome.

The contribution of rapid KATP channel gene mutation analysis to the clinical management of children with congenital hyperinsulinism

OBJECTIVE

In children with congenital hyperinsulinism (CHI), K(ATP) channel genes (ABCC8 and KCNJ11) can be screened rapidly for potential pathogenic mutations. We aimed to assess the contribution of rapid genetic testing to the clinical management of CHI.

DESIGN

Follow-up observational study at two CHI referral hospitals.

METHODS

Clinical outcomes such as subtotal pancreatectomy, (18)F-Dopa positron emission tomography-computed tomography (PET-CT) scanning, stability on medical treatment and remission were assessed in a cohort of 101 children with CHI.

RESULTS

In total, 32 (32%) children had pathogenic mutations in K(ATP) channel genes (27 in ABCC8 and five in KCNJ11), of which 11 (34%) were novel. In those negative at initial screening, other mutations (GLUD1, GCK, and HNF4A) were identified in three children. Those with homozygous/compound heterozygous ABCC8/KCNJ11 mutations were more likely to require a subtotal pancreatectomy CHI (7/10, 70%). Those with paternal heterozygous mutations were investigated with (18)F-Dopa PET-CT scanning and 7/13 (54%) had a focal lesionectomy, whereas four (31%) required subtotal pancreatectomy for diffuse CHI. Those with maternal heterozygous mutations were most likely to achieve remission (5/5, 100%). In 66 with no identified mutation, 43 (65%) achieved remission, 22 (33%) were stable on medical treatment and only one child required a subtotal pancreatectomy.

CONCLUSIONS

Rapid genetic analysis is important in the management pathway of CHI; it provides aetiological confirmation of the diagnosis, indicates the likely need for a subtotal pancreatectomy and identifies those who require (18)F-Dopa PET-CT scanning. In the absence of a mutation, reassurance of a favourable outcome can be given early in the course of CHI.

Adaptor protein-2 sigma subunit mutations causing familial hypocalciuric hypercalcaemia type 3 (FHH3) demonstrate genotype-phenotype correlations, codon bias and dominant-negative effects

The adaptor protein-2 sigma subunit (AP2σ2) is pivotal for clathrin-mediated endocytosis of plasma membrane constituents such as the calcium-sensing receptor (CaSR). Mutations of the AP2σ2 Arg15 residue result in familial hypocalciuric hypercalcaemia type 3 (FHH3), a disorder of extracellular calcium (Ca²⁺_o) homeostasis. To elucidate the role of AP2σ2 in Ca²⁺_o regulation, we investigated 65 FHH probands, without other FHH-associated mutations, for AP2σ2 mutations, characterized their functional consequences and investigated the genetic mechanisms leading to FHH3. AP2σ2 mutations were identified in 17 probands, comprising 5 Arg15Cys, 4 Arg15His and 8 Arg15Leu mutations. A genotype–phenotype correlation was observed with the Arg15Leu mutation leading to marked hypercalcaemia. FHH3 probands harboured additional phenotypes such as cognitive dysfunction. All three FHH3-causing AP2σ2 mutations impaired CaSR signal transduction in a dominant-negative manner. Mutational bias was observed at the AP2σ2 Arg15 residue as other predicted missense substitutions (Arg15Gly, Arg15Pro and Arg15Ser), which also caused CaSR loss-of-function, were not detected in FHH probands, and these mutations were found to reduce the numbers of CaSR-expressing cells. FHH3 probands had significantly greater serum calcium (sCa) and magnesium (sMg) concentrations with reduced urinary calcium to creatinine clearance ratios (CCCR) in comparison with FHH1 probands with CaSR mutations, and a calculated index of sCa × sMg/100 × CCCR, which was ≥ 5.0, had a diagnostic sensitivity and specificity of 83 and 86%, respectively, for FHH3. Thus, our studies demonstrate AP2σ2 mutations to result in a more severe FHH phenotype with genotype–phenotype correlations, and a dominant-negative mechanism of action with mutational bias at the Arg15 residue.

Factors Determining Patient Choice of Device for GH Therapy

AIM

To assess the factors determining patient choice of GH device, and whether offering free patient choice improves compliance with GH therapy.

METHODS

A prospective cross-sectional study performed on patients offered free choice of GH device in a regional growth clinic. In a subgroup having home delivery, GH compliance was assessed using ampoule counts.

RESULTS

125 patients (74 (59%) male), median (range) 9.30 (1.0-18.3) years were commenced on GH from January 2001 to March 2004, and offered free choice of device. 68 (54%) chose a needled device, and 57 (46%) needle-free. There was no statistical difference in age, sex or diagnostic category between the two groups. Light blue devices were more likely to be chosen by males (p=0.056). Questionnaires giving reasons for choosing a device were available in 40, and a further 50 gave reasons for both choosing a specific device and not choosing others. Other than choice of needled/needle-free device, the factor most likely to determine choice was 'ease of use'. Only 6 (4.8%) subsequently changed device, and compliance remained high but unchanged at approximately 90%.

CONCLUSIONS

There are no specific features which determine what GH device a patient will choose. For those units offering free patient choice, a wide range of different devices should be made available.

The emergence of type 2 diabetes in childhood

Type 1 diabetes (with predominant insulin deficiency) was until recently assumed to be the diagnosis of almost all children presenting with glucose intolerance. This requires insulin treatment via subcutaneous injections, and most patients develop microvascular and macrovascular complications in adulthood. Advances in genetics in the 1990s identified a group of genetic disorders of pancreatic beta-cell function (maturity-onset diabetes of the young) for which the outlook is better than type 1, genetic testing is available, and oral medication is the preferred treatment. In 2000, the first cases of type 2 diabetes (predominant insulin resistance) were reported in UK children, reflecting a trend seen in North America over the last 20 years. Affected children are usually overweight or obese, often female, pubertal, predominantly of ethnic minority (South Asian) origin and have a family history of type 2 diabetes. The diagnosis is aided by demonstration of insulin resistance, and may include measurement of fasting insulin and C-peptide, markers of the metabolic syndrome (fasting lipids, sex hormone binding globulin) and absence of autoantibodies against beta-cell components (e.g. glutamic acid decarboxylase). Management is aimed towards weight stabilization in the growing child, education on healthy lifestyles and the treatment of hyperglycaemia with both insulin and insulin-sensitizing agents. The underlying cause of type 2 diabetes in children is likely to be related to the epidemic of childhood obesity. There is emerging evidence of an appalling outlook for these young people in terms of miscarriages and microvascular and cardiovascular complications, which are likely to present an enormous economic and health services burden over the next 20 years.

The neuroendocrine sequelae of paediatric craniopharyngioma: a 40-year meta-data analysis of 185 cases from three UK centres

OBJECTIVES

The management of paediatric craniopharyngiomas was traditionally complete resection (CR), with better reported tumour control compared to that by partial resection (PR) or limited surgery (LS). The subsequent shift towards hypothalamic sparing, conservative surgery with adjuvant radiotherapy (RT) to any residual tumour aimed at reducing neuroendocrine morbidity, has not been systematically studied. Hence, we reviewed the sequelae of differing management strategies in paediatric craniopharyngioma across three UK tertiary centres over four decades.

METHODS

Meta-data was retrospectively reviewed over two periods before (1973-2000 (Group A: n = 100)) and after (1998-2011 (Group B: n = 85)) the introduction of the conservative strategy at each centre.

RESULTS

Patients had CR (A: 34% and B: 19%), PR (A: 48% and B: 46%) or LS (A: 16% and B: 34%), with trends reflecting the change in surgical approach over time. Overall recurrence rates between the two periods did not change (A: 38% vs B: 32%). More patients received RT in B than A, but recurrence rates were similar: for A, 28% patients received RT with 9 recurrences (32%); for B, 62% received RT with 14 recurrences (26%). However, rates of diabetes insipidus (P = 0.04), gonadotrophin deficiency (P < 0.001) and panhypopituitarism (P = 0.001) were lower in B than those in A. In contrast, post-operative obesity (BMI SDS >+2.0) (P = 0.4) and hypothalamic (P = 0.1) and visual (P = 0.3) morbidity rates were unchanged.

CONCLUSION

The shift towards more conservative surgery has reduced the prevalence of hormone deficiencies, including diabetes insipidus, which can be life threatening. However, it has not been associated with reduced hypothalamic and visual morbidities, which remain a significant challenge. More effective targeted therapies are necessary to improve outcomes.

Childhood idiopathic chondrolysis of the hip: MRI features

BACKGROUND

Childhood idiopathic chondrolysis of the hip (ICH) causes progressive destruction of the articular cartilage of the hip joint with associated bone remodelling. The MRI features of this disease have not previously been described.

OBJECTIVE

To document the MRI features of childhood ICH and determine which features may help distinguish ICH from other causes of hip joint destruction in the paediatric population.

MATERIALS AND METHODS

A retrospective review of the MRI examinations of children with clinically diagnosed ICH. All children had undergone synovial biopsy and/or joint aspiration with plain hip radiography to exclude causes of secondary chondrolysis.

RESULTS

Ten MRI examinations were performed on six children. Cartilage loss, small hip joint effusions, bone remodelling and significant regional muscle wasting were seen in all children. Cartilage loss was most severe in the central part of the joint. Synovial enhancement was not a constant feature of ICH. Serial imaging in three children showed disease progression.

CONCLUSIONS

MRI in ICH clearly demonstrates cartilage loss and enables delineation of bone and muscle abnormalities. It is helpful in the differential diagnosis of hip joint disease in children and may provide further information on the progression and aetiology of ICH.

Feeding Problems Are Persistent in Children with Severe Congenital Hyperinsulinism

BACKGROUND

Congenital hyperinsulinism (CHI) is a rare but severe disorder of hypoglycemia in children, often complicated by brain injury. In CHI, the long-term prevention of hypoglycemia is dependent on reliable enteral intake of glucose. However, feeding problems (FPs) often impede oral glucose delivery, thereby complicating the management of hypoglycemia. FPs have not been systematically characterized in follow-up in a cohort with CHI.

AIMS

We aimed to determine the prevalence, types, and persistence of FPs in a cohort of children with CHI and investigate potential causal factors.

METHODS

FPs were defined as difficulty with sucking, swallowing, vomiting, and food refusal (or a combination) in an observational study in 83 children in a specialized CHI treatment center. The prevalence of FPs at diagnosis, 6, and 12 months after diagnosis were noted. Genetic mutation status and markers of severity of CHI were tested for association with FPs.

RESULTS

A third of children with CHI had FPs (n = 28), of whom 93% required antireflux medication and 75% required nasogastric and gastrostomy tube feeding. Sucking and swallowing problems were present at diagnosis but absent later. Vomiting was present in 54% at 6 months, while food refusal was present in 68% at 6 months and 52% at 12 months. The age at commencing and stopping nasogastric tube feeding did not correlate with FPs frequency at 6 and 12 months. Children with FPs had severe hypoglycemia at diagnosis and required glucagon infusion more often [odds ratio (OR) (95% confidence intervals) (95% CI) 28.13 (2.6-300.1), p = 0.006] to normalize glucose levels. FPs were more frequent in those with diffuse CHI undergoing subtotal pancreatectomy [n (%) = 10 (35%) vs. 0 (0%), p < 0.001], in contrast to those with spontaneous resolution [6 (22%) vs. 32 (58%), p = 0.002]. Those undergoing focal lesionectomy also had reduced FPs at 6 months after diagnosis [OR (95% CI) 0.01 (0.0-0.2), R (2) = 0.42, p = 0.004]. These observations suggest that persistence of hyperinsulinism was associated with FPs.

CONCLUSION

FPs occur in a significant proportion of children with CHI. Severe hyperinsulinism, rather than nasogastric tube feeding or medications, is the main factor associated with FPs.

A pilot interventional study to evaluate the impact of cholecalciferol treatment on HbA1c in type 1 diabetes (T1D)

BACKGROUND

Higher 25(OH)D3 levels are associated with lower HbA1c, but there are limited UK interventional trials assessing the effect of cholecalciferol on HbA1c.

AIMS

(1) To assess the baseline 25(OH)D3 status in a Manchester cohort of children with type 1 diabetes (T1D). (2) To determine the effect of cholecalciferol administration on HbA1c.

METHODS

Children with T1D attending routine clinic appointments over three months in late winter/early spring had blood samples taken with consent. Participants with a 25(OH)D3 level <50 nmol/L were treated with a one-off cholecalciferol dose of 100,000 (2-10 years) or 160,000 (>10 years) units. HbA1c levels before and after treatment were recorded.

RESULTS

Vitamin D levels were obtained from 51 children. 35 were Caucasian, 11 South Asian and 5 from other ethnic groups. 42 were vitamin D deficient, but 2 were excluded from the analysis. All South Asian children were vitamin D deficient, with mean 25(OH)D3 of 28 nmol/L. In Caucasians, there was a negative relationship between baseline 25(OH)D3 level and HbA1c (r = -0.484, P < 0.01). In treated participants, there was no significant difference in mean HbA1c at 3 months (t = 1.010, P = 0.328) or at 1 year (t = -1.173, P = 0.248) before and after treatment. One-way ANCOVA, controlling for age, gender, ethnicity, BMI and diabetes duration showed no difference in Δ HbA1c level.

CONCLUSION

We report important findings at baseline, but in children treated with a stat dose of cholecalciferol, there was no effect on HbA1c. Further studies with larger sample sizes and using maintenance therapy are required.

Reduced Glycemic Variability in Diazoxide-Responsive Children with Congenital Hyperinsulinism Using Supplemental Omega-3-Polyunsaturated Fatty Acids; A Pilot Trial with MaxEPA(R.)

OBJECTIVE

Congenital hyperinsulinism (CHI) is a rare condition of hypoglycemia where therapeutic options are limited and often complicated by side-effects. Omega-3-polyunsaturated fatty acids (PUFA), which can suppress cardiac myocyte electrical activity, may also reduce ion channel activity in insulin-secreting cells. PUFA supplements in combination with standard medical treatment may improve glucose profile and may reduce glycemic variability in diazoxide-responsive CHI.

DESIGN

Open label pilot trial with MaxEPA(R) liquid (eicosapentaenoic and docosahexaenoic acid) PUFA (3 ml/day for 21 days) in diazoxide-responsive CHI patients (https://eudract.ema.europa.eu/, EudraCT number 201100363333).

METHODS

Glucose levels were monitored pre-treatment, end of treatment, and at follow-up by subcutaneous continuous glucose monitoring systems (CGMS) in 13 patients (7 girls) who received PUFA. Outcome measures were an improved glucose profile, reduced glycemic variability quantified by a reduction in the frequency of glucose levels <4 and >10 mmol/l, and safety of PUFA. All children were analyzed either as intention to treat (n = 13) or as per protocol (n = 7).

RESULTS

Mean (%) CGMS glucose levels increased by 0.1 mmol/l (2%) in intention to treat and by 0.4 mmol/l (8%) in per protocol analysis (n = 7). The frequency of CGMS <4 mmol/l was significantly less at the end of treatment than in the pre-treatment period [556 (7%) vs. 749 (10%)]. Similarly, the frequency of CGMS >10 mmol/l, was also less at the end of treatment [27 (0.3%) vs. 49 (0.7%)]. Except for one child with increased LDL cholesterol, all safety parameters were normal.

CONCLUSION

MaxEPA(R) was safe and reduced glycemic variability, but did not increase glucose profiles significantly in diazoxide-responsive CHI. The supplemental value of PUFA should be evaluated in a comprehensive clinical trial.

Heterozygous Insulin Receptor (INSR) Mutation Associated with Neonatal Hyperinsulinemic Hypoglycaemia and Familial Diabetes Mellitus: Case Series

Mutations in the insulin receptor (INSR) gene are associated with insulin resistance and hyperglycaemia. Various autosomal dominant heterozygous INSR mutations leading to hyperinsulinemic hypoglycaemia (HH) have been described in adults and children (more than 3 years of age) but not in the neonatal period. Family 1: A small for gestational age (SGA) child born to a mother with gestational diabetes presented with persistent hypoglycaemia, was diagnosed with HH and responded well to diazoxide treatment. Diazoxide was gradually weaned and discontinued by 8 months of age. Later, the younger sibling had a similar course of illness. On genetic analysis a heterozygous INSR missense variant p.(Met1180Lys) was found in the siblings, mother and grandfather but not in the father. Family 2: A twin preterm and SGA baby presented with persistent hypoglycaemia, which was confirmed as HH. He responded to diazoxide, which was subsequently discontinued by 10 weeks of life. Genetic analysis revealed a novel heterozygous INSR missense variant p.(Arg1119Gln) in the affected twin and the mother. Family 3: An SGA child presented with diazoxide responsive HH. Diazoxide was gradually weaned and discontinued by 9 weeks of age. Genetic analysis revealed a novel heterozygous INSR p.(Arg1191Gln) variant in the proband and her father. We report, for the first time, an association of INSR mutation with neonatal HH responsive to diazoxide therapy that resolved subsequently. Our case series emphasizes the need for genetic analysis and long-term follow up of these patients.

The effect of prelung transplant clinical status on post-transplant survival of children with cystic fibrosis

The aim of this study was to determine whether transplanting paediatric cystic fibrosis (CF) patients later in the course of their disease was detrimental to their post-transplant survival. Data was collected from 51 children with CF undergoing lung or heart-lung transplantation May 1988-March 1999. The following risk factors were tested by Cox proportional hazards modelling: age at transplant; sex; donor/recipient sex mismatch; donor/recipient cytomegalovirus (CMV) mismatch; cold and warm graft ischaemic times; and donor age. Pretransplant forced expiratory volume in one second (FEV1), minimum oxygen saturation obtained during 12 min walk (Sa,O2min), and a survival probability score (SP) calculated from FEV1, age adjusted resting heart rate, age, sex, blood haemoglobin (Hb), and serum albumin were then added to the model. None of the risk factors were significantly correlated with death during the study period. No evidence that clinical status prior to transplant has any effect upon the post-transplant survival of children with cystic fibrosis was found.

An observational study of type 2 diabetes within a large Australian tertiary hospital pediatric diabetes service

BACKGROUND

Type 2 diabetes mellitus (T2DM) is emerging as a significant clinical problem within the pediatric population.

OBJECTIVE

The objective of this study was to identify patients with T2DM in a large tertiary hospital diabetes service and examine aspects relating to clinical course and management.

METHODS

An initial audit of our diabetes service (over 6 yr) was followed by a 2-yr period of prospective case ascertainment to identify patients with T2DM. Comprehensive data collection was then undertaken in these individuals.

RESULTS

Within our service (n = 1574), 33 young people with T2DM were identified. Significant levels of co-morbidity were evident - dyslipidaemia (56%), microalbuminuria (45%), hypertension (30%) and abnormal retinal findings (25%). Hypertension was more likely in those with greater initial and follow-up body mass index (BMI) [mean (SD) BMI: 36.3 (5.0) vs. 28.0 (6.3) kg/m(2) , p = 0.001, and 36.8 (5.3) vs. 28.5 (7.8) kg/m(2) , p = 0.007, respectively] and BMI standard deviation score (SDS) [mean (SD) BMI SDS: 2.34 (0.30) vs. 1.72 (0.66), p = 0.001, and 2.26 (0.31) vs. 1.38 (0.87), p < 0.001, respectively], whereas abnormal retinal findings were seen in those with higher HbA1c values at last appointment [geometric mean (range) 10.9 (8.4-13.6) vs. 7.4 (5.6-12.5)%, p = 0.01) and those with greater increases in HbA1c over time (+4.1 (3.1) vs. +0.2 (1.9)%, p = 0.009). Of the 33,9 (27%) were lost to follow-up.

CONCLUSIONS

At present, T2DM in youth remains a low burden on our services. Patients with this diagnosis, however, have significant problems that present a major challenge to the development of effective management strategies.

The association of cardiac ventricular hypertrophy with congenital hyperinsulinism

OBJECTIVE

Ventricular hypertrophy (VH) has been observed in children with congenital hyperinsulinism (CHI), a condition of hypoglycaemia characterised by dysregulated insulin secretion, but the prevalence is not known.

PATIENTS AND METHODS

Cardiac assessment was performed in children (n=49) with CHI at diagnosis and follow-up. Two dimensional and Doppler echocardiography studies were used to assess cardiac structures, while M-mode study was used to measure left ventricular (LV) dimensions, subsequently converted to Z scores. Where possible, LV hypertrophy was confirmed by LV mass index (g/m(2.7)) >95th centile.

RESULTS

Cardiac structural lesions were found in 14 (28%) children. At initial echocardiography, VH was present in 31 (65%) children with median (range) LV posterior wall dimension in diastole Z scores of +1.6 (-2.4 to +5.8) and interventricular septal wall dimension in end diastole Z scores of +1.9 (-1.7 to +17.2). At follow-up echocardiography, performed after an interval of 178 (45-390) days, VH persisted in 16 (33%) children. In regression analysis, the presence of VH (odds ratio (95% confidence intervals) 1.1 (1.0-1.2), P=0.04) at initial echocardiography was correlated with maximum glucose requirement at diagnosis, indicating that severity of CHI at presentation may play a role in the pathogenesis of VH.

CONCLUSIONS

A significant proportion of children with CHI have cardiac structural lesions. A majority also have VH, which may be associated with the severity of CHI at diagnosis. VH may persist in some children, which requires careful long-term cardiac review.

Maternal attitude towards delaying puberty in girls with and without a disability: a questionnaire-based study from the United Arab Emirates

BACKGROUND

Parental anxiety about the impact of puberty/menses, particularly in girls with severe disability leads to seeking therapeutic pubertal suppression. We aim to explore maternal attitudes and reasons for seeking pubertal suppression.

METHODS

Mothers of girls receiving gonadotropin -releasing hormone analogue therapy in Mafraq hospital, Abu Dhabi were enrolled in the study. A semistructured interview was conducted to ascertain possible reasons for delaying puberty. The study group was divided into girls with a disability with central precocious puberty (CPP) or normal puberty and girls without a disability presenting with CPP.

RESULTS

42 mother-daughter pairs were enrolled and divided into two groups; group A: 15 girls with CPP with no disability; group B: 27 girls with disability (10 had CPP (group B1) and 17 had normal pubertal timing (group B2)). Mothers in group A aimed to delay puberty, while in group B, 13 (48%) mothers desired to halt puberty and 7 (26%) requested permanent surgical intervention. Fear of short stature (15, 100%), inability to cope psychologically (10, 67%) and fear of peer rejection (9, 60%) were the main concerns in group A. In group B, mothers were concerned about menstrual hygiene management (25, 92.5%), fear of child abuse or unwanted pregnancy (15, 55%) and fear of inability to express pain/discomfort with menstruation (8, 30%).

CONCLUSION

Mothers of girls with a disability commonly seek medical help to delay/halt puberty due to concerns about menstrual hygiene. Short final height was the main concern for girls without a disability. Culture and religion play an important role in puberty management in girls with a disability.