Haemophilia A and cardiovascular morbidity in a female SHAM syndrome carrier due to skewed X chromosome inactivation.

We have recently described a severe haemophilia A and moyamoya (SHAM) syndrome caused by Xq28 deletions encompassing F8 and the BRCC3 familial moyamoya gene. The phenotype includes haemophilia A, moyamoya angiopathy, dysmorphia and hypertension. The genetic analysis of the family of our SHAM patient demonstrated carrier state in proband's mother and sister. The patient's mother is apparently well, whereas his currently 18-years-old sister presents with mild haemophilia A, coarctation of the aorta, hypertension, and ventricular arrhythmia. We performed X chromosome inactivation assay based on HpaII methylation analysis of a polymorphic short tandem repeat (STR) in the X linked AR (androgen receptor) gene and used quantitative real-time RT PCR to measure the expression of genes from the deleted region in proband's family members. We found an extremely skewed X chromosome inactivation pattern in the female members of the family leading to preferential inactivation of the X chromosome without Xq28 deletion in patient's sister. We demonstrated differential expression of the genes from the deleted region in four members of the family, that tightly correlates with the clinical features. In conclusion, we show that the haematologic and cardiovascular morbidity and the discrepancy between patient's sister and mother despite the same genetic lesion are due to skewed X chromosome inactivation leading to clinically relevant differential expression of SHAM syndrome genes. This report highlights the role for BRCC3 in cardiovascular physiology and disease, and demonstrates that in some complex hereditary syndromes full diagnostics may require the examination of both genetic and epigenetic events.

Altered platelets' morphological parameters in children with type 1 diabetes ­ a case-control study.

BACKGROUND: Platelet hyperreactivity is a factor which contributes towards increased risk of cardiovascular events in adults with type 2 diabetes (T2DM). However, little is known about platelets' disturbances among children with type 1 diabetes (T1DM). The aim of the study was to investigate whether platelets' morphology or function are altered in children with type 1 diabetes, potentially predisposing them to cardiovascular events in the future. METHODS: The study group consisted of 389 children with T1DM during the 2008-2010 period. Patients with acute diabetes complications and ongoing infections were excluded from the study. An equinumerous (N = 389), age and sex-matched control group was assembled from children undergoing routine, minor surgical procedures in the same hospital. Platelet: count (PLT), mean volume (MPV), distribution width (PDW) and platelet large cell ratio (P-LCR) as well as HbA1c levels were measured. For statistical analysis we used Chi-square tests, the student's t-test, one-way analysis of variance (ANOVA), the Pearson's correlation coefficient and linear regression models in order to adjust for covariates. RESULTS: MPV, PDW and P-LCR were significantly higher among children with diabetes in comparison with the control group (MPV 10.47+/-0.85 fL vs 10.23+/-0.94 fL, p = 0.0007; PDW 12.09+/-1.80% vs 11.66+/-1.90%, p = 0.0032; P-LCR 28.21+/-6.15% vs 26.29+/-6.38%, p < 0.0001). PLT however, were shown to be similar (263.55+/-60.04 vs 268.77+/-65.78 10(3)/µl; p = 0.5637). In both cases and controls age was inversely correlated with platelet count (for study group: r = -0.30, p < 0.0001; for control group: r = -0.34, p < 0.0001), positively correlated with MPVs (r = 0.20, p < 0.0001; r = 0.26, p < 0.0001), PDW (r = 0.25, p < 0.0001 and r = 0.24, p < 0.0001) and P-LCR (r = 0.26, p < 0.0001; r = 0.26, p < 0.0001). After adjustment for confounding factors, higher platelet counts were associated with poorer metabolic control (beta = 0.20; 0.0001). CONCLUSIONS: Platelets of paediatric patients with T1DM show morphological evidence of hyperreactivity (higher MPV, PDW and P-LCR), while poorer metabolic control increases their number potentially predisposing the patients to future cardiovascular events.

Hypoglycemia and glycemic variability among children with acute lymphoblastic leukemia during maintenance therapy.

Symptomatic, chemotherapy-related hypoglycemia is a rare complication associated with the administration of purine analogs. The aim of the study was to evaluate 24 h glucose variability and frequency of hypoglycemia among patients with acute lymphoblastic leukemia (ALL) during maintenance therapy (MT). Eighteen children with ALL underwent continuous glucose monitoring (CGM). The number of episodes of hypoglycemia and glucose variability were analyzed. Serum alanine aminotransferase, asparagine aminotransferase, and γ-glutamyl transferase levels were measured as liver function markers. The mean glucose level in CGM equaled 105 ± 13 mg/dL, with standard deviation (SD) 13.8 ± 6.1 mg/dL, and the mean amplitude of glycemic excursions (MAGE) equaled 44.7 ± 19.9 mg/dL. Eight patients had at least one measurement below 70 mg/dL while four patients had measurements below 50 mg/dL. Children with hypoglycemia in CGM examination had a lower median body mass index standard deviation score (BMI Z-score) (-0.65 [-0.94 to -0.27] vs. -0.14 [-0.29 to 0.35]; p = 0.05) and shorter duration of MT (6.5 [4-15] vs. 22.5 [16.5-28] weeks; p = 0.004). Glucose variability parameters were strongly correlated with BMI Z-score and liver function enzymes. Hypoglycemia, particularly at night-time, may develop as a complication of MT in children with ALL. The risk factors for low glucose level are low BMI Z-score and initiation of MT.

[Evaluation of preserved insulin secretion in children and adolescents with type 1 diabetes]. / Ocena zachowanej przetrwalej insulinosekrecji u dzieci i mlodziezy z cukrzyca typu 1.

INTRODUCTION: The pathogenesis of type 1 diabetes is connected with immune-mediated beta-cell destruction leading to insulin deficiency. The majority of patients will become completely incapable of insulin secretion within a few years, however, some individuals will have persistent beta-cell function years after the diagnosis of diabetes. Despite clinical symptoms of insulin deficiency, residual beta-cell secretion can modify the clinical course and can be an independent factor influencing the delay of development of chronic diabetic complications. The aim of the study was to compare a 10-year clinical course in children with type 1 diabetes with and without preserved beta-cell secretion. MATERIAL AND METHODS: 72 children and adolescents with diabetes lasting for minimum 10 years and available biological material to c-peptide evaluation (3-4 years and 10 years from the onset of diabetes) were chosen from 768 children with type 1 diabetes. We assessed fasting c-peptide and recruited 23 out of 72 patients whose concentration of c-peptide was below or over 0.23 ng/ml at all time points (this cut point derives from the definition of preserved beta-cell function according to DCCT). Afterwards we divided children into two subgroups: A (n=13) - without insulin secretion and B (n=10) - with preserved beta-cell function during 10 years of observation. We assessed markers of beta-cell autoimmunity (ICA, GADA, IA2, IAA) in the examined groups. Insulin requirement and concentration of glycated hemoglobin (assessed as the year mean from four measurements in each year) were compared between group A and B. RESULTS: The age at onset of diabetes in children from both examined groups was similar. All children from group B and 12/13 from group A were positive for at least one type of the screened autoantibodies. There was no difference in insulin requirement between the groups (p=0.6). The level of glycated hemoglobin was significantly lower in group B during a 10-year observational period (p=0.04). CONCLUSION: Repeated measures of c-peptide can enable us to define two groups of patients with immune-mediated diabetes with different levels of disease and metabolic control.

Neonatal diabetes in a child positive for islet cell antibodies at onset and Kir6.2 activating mutation.

In contrast to the autoimmune type 1 diabetes, patients with monogenic diabetes due to KCNJ11 mutations do not have pancreatic auto-antibodies at onset. Here we describe a patient diagnosed at the age of 12 weeks that showed ICA at diagnosis, yet has been tested with positive result for KCNJ11 mutation.

[Tissue-specific autoimmunity in patients with idiopathic diabetes]. / Analiza tkankowo swoistej odpowiedzi humoralnej u chorych z cukrzyca idiopatyczna typu 1.

INTRODUCTION: According to the WHO classification, type 1 diabetes is divided into type 1A - autoimmune and type 1B - idiopathic. The pathogenesis of the latter remains unknown. Clinical observations confirm that type 1 diabetes is often associated with the presence of other organ-specific autoantibodies. Besides, the idiopathic type 1 diabetes is suggested as resulted form immune-related beta cell destruction with the defect of humoral response. THE AIM: of the study was to verify the above-mentioned hypothesis by an evaluation of the prevalence of thyroid and coeliac antibodies in children with idiopathic diabetes. MATERIAL AND METHODS: The study groups consisted of 37 patients with idiopathic diabetes (group 1B) and 108 patients with autoimmune diabetes (1A). The examined groups were chosen from 569 children with newly diagnosed type 1 diabetes. Anti-islet antibodies (ICA) and antibodies to endomysium were detected by indirect immunofluorescence. Antibodies to tissue transglutaminase were measured by the immunoenzymatic method, whereas the measurement of autoantibodies to insulin, to tyrosine phosphatase and to glutamic acid decarboxylase was determined by radioimmunoassay. RESULTS: Thyroid antibodies were detected in 5.9% of the examined patients from group 1B and 14.7% from group 1A. The frequency of the presence of tissue transglutaminase autoantibodies in both groups was similar (9.4% in 1B and 8.3% in 1A) and in case of endomysial antibodies it was slightly higher in group 1B (9.4% vs 4.8%, p=0.39). CONCLUSION: Since the prevalence of tissue specific autoantibodies is similar in both presentations of type 1 diabetes it is unlikely that a humoral defect of immune response in idiopathic diabetes is observed in this group of patients.

[Idiopathic type 1 diabetes: a heterogenous disease or result of our ignorance?]. / Idiopatyczna postac cukrzycy typu 1: heterogenna jednostka chorobowa czy wynik naszej niewiedzy?

Based on etiology a new classification for diabetes mellitus was proposed by the Experts of WHO in 1999. According to the classification, type 1 diabetes was subclassified as type 1A (autoimmune) and type 1B (idiopathic). Both forms result from the destruction of beta cells, however in type 1A the process is immune-mediated but in type 1B the origin of the beta cells impairment is still unknown. Moreover, subtype B is considered to be very heterogeneous and the diagnostic criteria are still not clear. The purpose of this article was to review studies on the pathogenesis of idiopathic type 1 diabetes.

[Post-exercise microalbuminuria in newly diagnosed type 1 diabetic children - preliminary report]. / Mikroalbuminaria powysilkowa u dzieci ze swiezo rozpoznana cukrzyca typu 1 - doniesienie wstepne.

THE AIM: of this study was the evaluation of some factors having an influence on post-exercise albuminuria level in children with newly diagnosed type 1 diabetes as a prognostic factor of developing nephropathy. MATERIAL AND METHODS: 24 newly diagnosed type 1 diabetic children, aged 5.5-16.9 years, mean 10.2+/-3.2, were examined. In order to provoke albuminuria the patients underwent standardized exercise test using treadmill ramp according to the Bruce protocol. Pre- and post-exercise albuminuria and C-peptide levels by radioimmunoassay were evaluated. In urine of patients the albumin / creatinine ratio (ACR) was determined. RESULTS: the tendency towards an increase in ACR ratio in children after exercise (10.5 mg/g (4-27.5) in comparison to the value in pre-exercise urine (7 mg/g (2.5-13), p=0.17) was observed. In 67% of patients (16/24) the ACR ratio was higher in post-exercise urine. In 25% of children (6/24) the ACR ratio was above 30 mg/g which was considered as post-exercise microalbuminuria. Next, parameters of metabolic control of type 1 diabetes were compared between patients with and without post-exercise microalbuminuria. No differences in the serum glucose, HbA1c, BMI, triglycerides, total cholesterol, insulin dose, frequency of ketoacidosis and C-peptide level between these groups of children were noted. CONCLUSIONS: we concluded that the post-exercise microalbuminuria as a marker of diabetic nephropathy risk may be observed in some patients already at the clinical onset of type 1 diabetes but further evaluation is needed to verify this hypothesis.

[Factors affecting C-peptide level during the first year of type 1 diabetes in children]. / Uwarunkowania stezenia peptydu C w pierwszym roku klinicznie jawnej cukrzycy typu 1 u dzieci.

BACKGROUND: C-peptide level is the most reliable factor evaluating the endogenous insulin secretion in patients with type 1 diabetes. OBJECTIVES: The aim of the study was to investigate whether the age at onset, gender, presence of autoantibodies and ketoacidosis at diagnosis and insulin requirement, HbA1c levels could be applied to predict the C-peptide levels in the first year of type 1 diabetes in children. MATERIAL AND METHODS: 122 type 1 diabetic children, aged: 2-18 years (average 11.2), 44 female and 78 male were studied. Fasting C-peptide levels were examined by radioimmunoassay at diagnosis, after 10 days and after 1, 2, 3, 6 and 12 months of disease. At diagnosis islet cell antibodies (ICA) were detected by indirect immunofluorescence, antibodies to glutamic acid decarboxylase (GADA) and tyrosine phosphatase antibodies (IA2A) were measured by microradioimmunoprecipitation assay. RESULTS: Age at onset was positively correlated to C-peptide levels at each evaluated point of the disease (r=0.3-0.46, p<0.0001). One year after diagnosis C-peptide levels decreased in ICA(+) (p<0.04) and GADA(+) (p<0.002) patients but not in ICA(-) or GADA(-) children. There was no significant difference between the IA2A-positive and negative subjects in the C-peptide levels at 12th month of disease. C-peptide level was also related to ketoacidosis at diagnosis, insulin requirement and HbA1c levels during the first year of type 1 diabetes. Logistic regression analysis showed that male, younger age, low pH, higher HbA1c and insulin requirement at onset were associated with decreased C-peptide level at diagnosis (p<0.00002). CONCLUSIONS: Young age, presence of diabetes-related autoantibodies and hyperglycaemia with severe acidosis at the disease onset may be associated with a decreased residual insulin secretion in type 1 diabetes in children.