Randa M. Matter

PLATELET MICROPARTICLES IN IMMUNE THROMBOCYTOPENIC PURPURA IN PEDIATRICS

Immune thrombocytopenic purpura (ITP) is one of the most common hemorrhagic disorders in childhood. Platelet microparticles (PMPs) arise with platelet activation with procoagulant activity. Elevated PMP levels in adult ITP were reported to be thrombogenic in certain settings. However, their clinical significance in pediatric ITP was not studied. The aims of this study were to assess PMP levels in ITP in children and adolescents, and its correlation with clinical status and bleeding score. The study included 40 ITP patients (20 acute aged 9 ± 2.19 years and 20 chronic aged 10.8 ± 4.7 years) randomly selected from the Hematology Clinic, Childrens Hospital, Ain Shams University, Cairo, Egypt, and 30 sex- and age-matched healthy controls aged 9 ± 3.28 years. Patients were subjected to detailed history, assessment of bleeding score, complete hemogram, cytological bone marrow examination, and PMP quantification in peripheral blood by flow cytometry. Acute ITP patients had significant increase in PMPs, PMP/platelet count, and PMP percent compared to controls (P = .002, P < .0001, P < .0001, respectively) and compared to chronic ITP patients (P < .0001, P < .0001, P < .0001, respectively). PMPs were significantly decreased in chronic ITP patients compared to controls (P = .001), but PMP/platelet and PMP percent showed highly significant increase in chronic ITP (P < .0001). No correlation was evident between PMP levels and platelet count in either group (P > .05). Neither higher bleeding score nor thrombotic manifestations were observed in the studied ITP patients with high PMP levels. Elevated PMP levels may be protective against severe bleeding events in pediatric ITP. The role of PMP studies in deciding the management plan of childhood and adolescent ITP needs further evaluation.

Gradient-echo magnetic resonance imaging study of pancreatic iron overload in young Egyptian beta-thalassemia major patients and effect of splenectomy

BackgroundThalassemic patients suffer from diabetes mellitus secondary to hemosiderosis.AimsThe study aimed to evaluate pancreatic iron overload by T2*-weighted Gradient-echo magnetic resonance imaging (MRI) in young beta-thalassemia major patients and to correlate it with glucose disturbances, hepatic hemosiderosis, serum ferritin and splenectomy.MethodsForty thalassemic patients (20 non diabetic, 10 diabetic, and 10 with impaired glucose tolerance) were recruited from Pediatric Hematology Clinic, in addition to 20 healthy controls. All patients underwent clinical assessment and laboratory investigations included complete blood count, liver function tests, serum ferritin and oral glucose tolerance test (OGTT). A T2*-weighted gradient-echo sequence MRI was performed with 1.5 T scanner and signal intensity ratio (SIR) of the liver and the pancreas to noise were calculated.ResultsSignificant reduction in signal intensity ratio (SIR) of the liver and the pancreas was shown in thalassemic patients compared to controls (P < 0.0001), Thalassemic patients with abnormal glucose tolerance; including diabetics and thalassemics with impaired glucose tolerance; displayed a higher degree of pancreatic and hepatic siderosis compared to thalassemics with normal glucose tolerance or controls (P < 0.001, P < 0.0001). Splenectomized thalassemic patients had significantly lower SIR of pancreas compared to non splenectomized patients (P < 0.05). A strong correlation was present between hepatic and pancreatic siderosis in studied patients (P < 0.001).Conclusionspancreatic siderosis can be detected by T2* gradient-echo MRI since childhood in thalassemic patients, and is more evident in patients with abnormal glucose tolerance. After splenectomy, iron deposition may be accelerated in the pancreas. Follow up of thalassemic patients using pancreatic MRI together with intensive chelation therapy may help to prevent the development of overt diabetes.

THROMBIN ACTIVATABLE FIBRINOLYSIS INHIBITOR (TAFI): Relationship to Hemostatic Alteration in Patients with β-Thalassemia

Profound hemostatic changes have been observed among thalassemic patients. Thrombin activatable fibrinolysis inhibitor (TAFI) is a newly discovered protein that potentially attenuates fibrinolysis. The authors aimed to investigate plasma level of TAFI in β-thalassemia patients in relation to clinical severity and hemostatic alteration. Fifty-one thalassemic patients (mean age 10.79 ± 5.59 years) (21 splenectomized thalassemia major patients, 18 nonsplenectomized thalassemia major patients, 12 nonsplenectomized thalassemia intermedia) were recruited from Pediatric Hematology Clinic, Ain Shams University; in addition, 32 healthy age- and sex-matched controls (10.31 ± 5.58 years) were also included. In addition to clinical assessment, laboratory investigations included complete blood count (CBC), hemoglobin electrophoresis, prothrombin time (PT), activated partial thromboplastin time (PTT), liver function tests, viral hepatitis markers, serum ferritin, and plasma TAFI levels. Nine out of 51 patients (17.5%) suffered from bleeding manifestations mainly in the form of epistaxis; none of the studied patients had thromboembolism. Significant reduction in TAFI levels was shown in thalassemic patients compared to controls (P < .0001), in splenectomized compared to nonsplenectomized thalassemia group (P < .0001), and in thalassemia major compared to thalassemia intermedia group (P < .0001). Negative correlation was present between TAFI levels and both liver enzymes and serum ferritin levels (P < .05). Thalassemic patients suffering from bleeding showed lower mean TAFI levels compared to those not suffering from bleeding (P < .001). Marked reduction in TAFI levels was observed in thalassemic patients with splenectomy, altered liver functions, and poor chelation who therefore might be at a higher risk for altered hemostasis.

Plasma Adrenomedullin level in Egyptian children and Adolescents with type 1 diabetes mellitus: relationship to microvascular complications

BackgroundAdrenomedullin (AM) is known to be elevated in different clinical situations including diabetes mellitus (DM), but its potential role in the pathogenesis of vascular complications in diabetic children and adolescents is to be clarified. Hence, the study aimed at assessment of plasma adrenomedullin levels in children and adolescents with type 1 DM and correlation of these levels with metabolic control and diabetic microvascular complications (MVC).MethodsThe study was performed in the Diabetes Specialized Clinic, Childrens Hospital of Ain Shams University in Cairo, Egypt. It included 55 diabetic children and adolescents (mean age 13.93 ± 3.15 years) who were subdivided into 40 with no MVC and 15 with MVC. Thirty healthy subjects, age-and sex- matched were included as control group (mean age 12.83 ± 2.82 years). Patients and controls were assessed for glycosylated hemoglobin (HbA1c) and plasma adrenomedullin assay using ELISA technique.ResultsMean plasma AM levels were significantly increased in patients with and without MVC compared to control group, (110.6 pg/mL, 60.25 pg/mL and 39.2 pg/mL respectively) (P < 0.01) with higher levels in those with MVC (P < 0.05). Plasma AM levels were positively correlated with both duration of diabetes (ρ = 0.703, P < 0.001) and glycemic control (HbA1c) (ρ = 0.453, P < 0.001).ConclusionHigher plasma AM levels in diabetics particularly in those with MVC & its correlation with diabetes duration and metabolic control may reflect the role of AM in diabetic vasculopathy in the pediatric age group.

Predictors of bone disease in Egyptian prepubertal children with β-thalassaemia major

Introduction Thalassaemic osteopathy is a multifactorial disorder and limited information exists about bone accrual and bone mineral density (BMD) in prepubertal thalassaemic children. The study aimed to investigate some potential genetic and biochemical bone markers as possible early predictors of BMD variations in children with β-thalassaemia major (TM) before puberty. Material and methods Thirt-one prepubertal children with β-TM, and 43 matched controls were subjected to BMD assessment by dual energy X-ray absorptiometry (DEXA). Vitamin D receptor (VDR) gene polymorphisms (Bsm1, Fok1) and the biochemical bone markers serum osteocalcin and propeptide I procollagen (CPIP) and urinary deoxypyridinoline (DPD) excretion were assessed. Results Bone mineral density was reduced in 25% of thalassaemics at the spine and 15.4% at the hip region. Significantly higher levels of urinary DPD and lower serum osteocalcin and CPIP levels were found in the studied thalassaemic children compared to controls (p < 0.001). A significant negative correlation was present between BMD in spine and hip and the patients’ age (r = −0.6367, p = 0.0002 and r = −0.616, p = 0.00079, respectively). There was a significant reduction in BMD in males compared to females. Reduced BMD was more frequent in male patients with genotypes bb and Ff but not in females. Bone mineral density was not related to the studied biochemical bone markers, mean pre-transfusion haemoglobin or serum ferritin. Conclusions Routine BMD screening with DEXA is proposed to be a sensitive predictor for early bone changes, particularly at the lumbar spine. DR gene polymorphisms of Bsm1 and Fok1 polymorphisms may be determinants of BMD in Egyptian prepubertal male thalassemics

Determinants of platelet count in pediatric patients with congenital cyanotic heart disease: Role of immature platelet fraction

OBJECTIVES Congenital heart defects are common noninfectious causes of mortality in children. Bleeding and thrombosis are both limiting factors in the management of such patients. We assessed the frequency of thrombocytopenia in pediatric patients with congenital cyanotic heart disease (CCHD) and evaluated determinants of platelet count including immature platelet fraction (IPF) and their role in the pathogenesis of thrombocytopenia. METHODS Forty-six children and adolescents with CCHD during pre-catheter visits were studied; median age was 20.5 months. Complete blood count including IPF as a marker of platelet production and reticulated hemoglobin content (RET-He) as a marker of red cell production and iron status were done on Sysmex XE 2100 (Sysmex, Japan). C-reactive protein, prothrombin time (PT), Activated partial thromboplastin time (APTT) were also assessed. RESULTS Thrombocytopenia was found in 6 patients (13%). PT was prolonged (P = .016) and IPF was significantly higher in patients with thrombocytopenia compared with patients with normal platelet count (14.15 ± 5.2% vs 6.68 ± 3.39%; P = .003). Platelet count was negatively correlated with IPF while significant positive correlations were found between IPF and hemoglobin, red blood cells (RBCs) count, hematocrit (Hct), PT, reticulocytes count, and immature reticulocyte fraction. CONCLUSIONS We suggest that elevated IPF in CCHD patients with thrombocytopenia may denote peripheral platelets destruction as an underlying mechanism. Hemoglobin level, RBCs count, Hct, and RET-He were not significant determinants for platelet count in CCHD.

Serum angiogenin level in sickle cell disease and beta thalassemia patients.

Introduction: Angiogenesis has been investigated in different kinds of anemia. However, its role as a marker of angiogenesis has not been investigated in thalassemia or sickle cell disease (SCD). Objectives: We aimed to investigate serum angiogenin level in children and adolescents with beta thalassemia or SCD and its relation to possible risk factors of angiogenesis. Materials and Methods: This study included; 32 β-thalassemia major (β-TM) patients aged 14.2 ± 3.8 years, 20 β-thalassemia intermedia (β-TI) patients aged 14.3 ± 4.8 years, 20 SCD patients aged 14.1 ± 2.4 years; 8 with (HbSS) and 12 with sickle thalassemia (HbS/β-thalassemia) and 35 age and sex-matched controls. Data collected regarding; age, sex, disease duration, blood transfusion frequency, transfusion index, chelation type and duration, CBC, Hb electrophoresis, serum ferritin and serum angiogenin level (by ELISA). Results: Angiogenin level was significantly higher in patients with SCD [250 (100–300) pg/mL] compared to β-TM [180 (140–230) pg/mL] and controls [89 (80–103) pg/mL] (P < .001) especially those with HbSS (P = .06). There was a significant negative correlation between serum angiogenin and age of patients, age of onset and duration of chelation in β-TM (P < .01, P < .001, P = .003) and β-TI (P = .009, P = .03, P < .001) and with serum ferritin in β-TI group (r = −0.573, P = .008). In SCD, angiogenin level was negatively correlated with both frequency of blood transfusion (r = −0.731, P < .001) and duration of hydroxyurea therapy (P = .017). Conclusions: High angiogenin level detected among patients with SCD may be negatively influenced by regular blood transfusion and hydroxyurea therapy, while; early onset of chelation therapy may decrease angiogenin level in β-TM.

Study of Visfatin Level in Type 1 Diabetic Children and Adolescents

BACKGROUND: Visfatin is an intracellular enzyme, known as nicotinamide phosphoribosyltransferase (Nampt) and pre-B-cell colony-enhancing factor (PBEF-1). It has insulin-mimetic effects and lowers plasma glucose levels. AIM: The aim of the work was to assess serum concentration of Visfatin in type 1 diabetic children and adolescents and study its relationships with duration of diabetes, body mass index (BMI), glycemic control, insulin dosage, lipid profile and microvascular complications. MATERIAL AND METHODS: Fifty children and adolescents with type 1 diabetes mellitus were recruited with 30 ages and gender-matched healthy subjects. They were subjected to history taking; anthropometric measurements and chronic diabetic complications were recorded if present. Laboratory analysis included urinary microalbumin, serum triglycerides, HDL, LDL, cholesterol, fasting blood glucose, glycosylated Hb (HbA1c) and serum visfatin which was measured with enzyme-linked immunosorbent assay. RESULTS: Diabetic patients showed highly significant decrease in the level of visfatin compared to the control group (P = 0.0001). There was significant further decrease in visfatin level in diabetics with microalbuminuria (n = 13) compared to normoalbuminuric patients (n = 37) (P = 0.015). There was highly significant inverse correlation between visfatin level with age (r = -0.379, p = 0.007), BMI (r = -0.418, p = 0.003), waist circumference (r = -0.430, p = 0.002), hip circumference (r = -0.389, p = 0.005) and microalbuminuria (r = -0.323, p = 0.022). CONCLUSIONS: Type 1 diabetic children and adolescents had a significantly lower visfatin level compared to controls. A marked decrease in the level of visfatin was shown in patients with microalbuminuria with an inverse correlation with BMI suggesting an important role of visfatin in the pathogenesis of type 1 diabetics and type 1 diabetic nephropathy.

Pancreatic functions in adolescents with beta thalassemia major could predict cardiac and hepatic iron loading: relation to T2-star (T2*) magnetic resonance imaging

The aim of this study is to assess the correlation between cardiac and hepatic T2* MRI findings with the endocrine and exocrine pancreatic functions in known patients with β-thalassaemia major (β-TM). A total of 50 adolescent patients with β-TM and 44 healthy controls were investigated via: serum amylase, lipase, triglyceride index, oral glucose tolerance test and T2* MRI, to assess iron content in the heart and liver. Diabetes was found in 20%, and 40% of patients had impaired fasting glucose (IFG). Cardiac T2* was less than 10 ms in 22% indicating heavy load with iron in cardiac tissues. There was a significant decrease in median serum amylase (63.5 vs 87.5 IU/L, p=0.003) and lipase (63 vs 90 IU/L, p=0.017) among patients in comparison with the control group. Patients with β-TM and diabetes had lower serum amylase (32 vs 68 IU/L), lipase (28 vs 79 IU/L), cardiac and hepatic T2* MRI (7 vs 25.5 ms; 3 vs 6 ms, p<0.001 for all) than those without diabetes. Similar results were found among patients with IFG when compared with others (p<0.001 for all). Cardiac and hepatic T2* were inversely correlated to triglyceride index (r=−0.376, p=0.014 and r=−0.475, p=0.001, respectively) and positively correlated to amylase (r=0.791 and r=0.790) and lipase (r=0.784 and r=0.783; p<0.001 for all). The endocrine and exocrine pancreatic functions might become an equivalent predictor to cardiac and hepatic iron overload, especially in countries where MRI is not available or where it is expensive. The early occurrence of these abnormalities warrants more intensive chelation therapy.