Circulating angiopoietin-2 levels in children and adolescents with type 1 diabetes mellitus: relation to carotid and aortic intima-media thickness.

BACKGROUND: Angiopoietin-2 is a growth factor involved in the pathophysiology of vascular and inflammatory diseases such as arteriosclerosis. Carotid or aortic scans provide noninvasive screening tools for assessment of preclinical atherosclerosis in high-risk children. AIM: We assessed serum angiopoietin-2 in children and adolescents with type 1 diabetes mellitus as a potential marker for vascular complications in relation to glycemic control, inflammation and vascular structure. METHODS: Sixty patients with type 1 diabetes were divided into 2 groups according to the presence of micro-vascular complications and compared with 30 healthy controls. High-sensitivity C-reactive protein (hs-CRP), hemoglobin A1c (HbA1c), urinary albumin/creatinine ratio, serum angiopoietin-2, carotid and aortic intima-media thickness (CIMT and AIMT) were measured. RESULTS: CIMT, AIMT and serum angiopoietin-2 levels were significantly increased in patients with and without micro-vascular complications compared with controls, and the highest levels were in patients with complications (p < 0.001). Angiopoietin-2 was higher in patients with microalbuminuria than normoalbuminuric group (p < 0.001). Fasting blood glucose, HbA1c, hs-CRP, CIMT and AIMT were independently related to angiopoietin-2 in multiple regression analysis. Disease duration, hyperglycemia, poor glycemic control, hypercholesterolemia, inflammation and angiopoietin-2 were independent factors contributing to atherosclerosis risk. CONCLUSION: The relation between angiopoietin-2 and assessed parameters of vascular structure in type 1 diabetes reflects a state of endothelial injury and highlights the role of disturbed angiogenesis and vascular inflammation in the occurrence of diabetic complications.

Serum YKL-40 in young patients with ß-thalassemia major: Relation to hepatitis C virus infection, liver stiffness by transient elastography and cardiovascular complications.

BACKGROUND: YKL-40 is an inflammatory glycoprotein involved in endothelial dysfunction and elevated in sera of patients with liver diseases. AIM: To determine serum YKL-40 among 50 children and adolescents with ß-thalassemia major (ß-TM) compared to 35 healthy controls and assess its relation to liver stiffness by transient elastography (TE), markers of hemolysis, iron overload and various hemolysis-associated complications. METHODS: ß-TM patients asymptomatic for heart disease were studied stressing on chelation therapy, serum ferritin, liver iron concentration (LIC), cardiac T2* and YKL-40. Echocardiography and TE were performed. RESULTS: Liver cirrhosis (METAVIR F4; TE values>12.5kPa) was encountered in 32%. HCV-positive patients had significantly higher WBC count, alanine transaminase (ALT) and serum ferritin than HCV-negative patients. YKL-40 levels were significantly higher in ß-TM patients compared with control (p<0.001). YKL-40 was significantly higher among patients with heart disease (p=0.014) or hepatitis C virus (p=0.004) than those without. YKL-40 was correlated with liver stiffness and the degree of hepatic fibrosis being highest among patients with F4 stage (p<0.001). The YKL-40 cutoff to identify ß-TM patients with liver cirrhosis or heart disease was determined. Patients treated with combined chelation therapy had significantly lower levels of YKL-40 than the monotherapy group (p<0.001). YKL-40 was positively correlated with transfusion index, ALT, lactate dehydrogenase, serum ferritin and LIC but negatively correlated with cardiac T2*. CONCLUSION: YKL-40 is a promising marker of cardiovascular disease and liver siderosis in ß-TM patients. The combination of YKL-40 and TE provides a reliable method to assess hepatic fibrosis in young ß-TM patients.

Assessment of the frequency of regulatory T cells (CD4+CD25+CD127-) in children with hemophilia A: relation to factor VIII inhibitors and disease severity.

A rapidly growing evidence showed that regulatory T cells (Tregs) play a crucial role in tolerance to coagulation factors and may be involved in the pathogenesis of inhibitor formation in patients with hemophilia. We determined the percentage of Tregs (CD4CD25CD127) in 45 children with hemophilia A compared with 45 healthy controls, and assessed their relation to the clinical characteristics of patients and factor VIII (FVIII) inhibitors. Patients were studied stressing on frequency of bleeding attacks, joint pain, history of viral hepatitis, and the received therapy (FVIII precipitate/cryotherapy). FVIII activity and FVIII inhibitors were assessed with flow cytometric analysis of CD4CD25CD127 Tregs. According to residual FVIII activity levels, 30 patients (66.7%) had mild/moderate hemophilia A, whereas 15 (33.3%) patients had severe hemophilia A. The frequency of Tregs was significantly lower among all patients with hemophilia A compared with controls (2.59 ± 1.1 versus 3.73 ± 1.12%; P = 0.002). Tregs were significantly decreased among patients with FVIII inhibitors compared with the inhibitor-negative group (P < 0.001). Patients with hematuria or severe hemophilia A had lower Tregs levels than those without (P = 0.34 and P = 0.011, respectively). A significant positive correlation was found between the percentage of Tregs and FVIII among hemophilia A patients. ROC curve analysis revealed that the cut-off value of Tregs at 1.91% could differentiate patients with and without FVIII inhibitors, with a sensitivity of 100% and a specificity of 91.3%. We suggest that alteration in the frequency of Tregs in young patients with hemophilia A may contribute to inhibitor formation and disease severity.