Azza A.G. Tantawy

Single photon emission tomography (SPECT) study of regional cerebral blood flow in normoalbuminuric children and adolescents with type 1 diabetes.

Abstract: Cerebral damage in diabetes can be related to chronic hyperglycemia and recurrent severe hypoglycemia as well as due to the associated vasculopathy. The pattern of regional cerebral blood flow using cerebral single photon emission tomography (SPECT) was evaluated in normoalbuminuric type 1 diabetic children and adolescents and its relation to the metabolic control and cognitive functions. Thirty‐one type 1 diabetics aged 10–18 yr (mean 14.7 ± 3.4) were included, 16 males and 15 females, divided into four groups: group I (n = 8) with history of recurrent severe hypoglycemia (≥ 3); group II (n = 8) with history of severe diabetic ketoacidosis (≥ 3); group III (n = 7) with recurrent minor hypoglycemia 
(≥ 3/week); and group IV (n = 8) with controlled diabetes. The control group (V) comprised seven healthy children, aged 10–18 yr (mean 14.2 ± 3.1). SPECT was done using technetium‐99m hexamethyl propylene amine oxime. There was significant brain hypoperfusion in diabetics compared with controls, mainly in the basal ganglia (p < 0.01) and frontal regions (p < 0.01), with less changes in parietal and temporal regions. These changes were not related to the age, sex, diabetes duration, mean blood glucose or HbA1C. Basal ganglia hypoperfusion was significant in groups I (p < 0.01) and II (p < 0.01) compared with controlled diabetics. There was no correlation between cerebral SPECT changes and cognitive scores in type 1 diabetics.

Circulating platelet and erythrocyte microparticles in young children and adolescents with sickle cell disease: Relation to cardiovascular complications

Sickle cell disease (SCD) is characterized by a complex vasculopathy, consisting of endothelial dysfunction and increased arterial stiffness, with a global effect on cardiovascular function. The hypercoagulable state may result from chronic hemolysis and circulating cell-derived microparticles (MPs) originating mainly from activated platelets and erythrocytes. We measured the levels of platelet and erythrocyte-derived MPs (PMPs and ErMPs) in 50 young SCD patients compared with 40 age- and sex-matched healthy controls and assessed their relation to clinicopathological characteristics and aortic elastic properties. Patients were studied stressing on the occurrence of sickling crisis, transfusion history, hydroxyurea therapy, hematological, and coagulation profile as well as flow cytometric expression of PMPs (CD41b+) and ErMPs (glycophorin A+). Echocardiography was performed to assess aortic stiffness and distensibility, left ventricular function and pulmonary artery pressure. Both PMPs and ErMPs were significantly elevated in SCD patients compared with control group (p < 0.001). SCD patients had significantly elevated d-dimer and von Willebrand factor antigen (vWF Ag) levels with lower antithrombin III compared with controls (p < 0.001). Aortic stiffness index and pulmonary artery pressure were significantly higher in SCD (p < 0.001), whereas aortic strain and aortic distensibility were significantly lower (p < 0.001) compared with controls. MPs levels were significantly increased in SCD patients with pulmonary hypertension, acute chest syndrome, and stroke as well as those who had history of thrombosis or splenectomy (p < 0.001). Also, patients in sickling crisis during the study had higher PMPs and ErMPs levels than those in steady state (p < 0.001). Patients on hydroxyurea therapy had lower MPs levels than untreated patients (p < 0.001). PMPs and ErMPs were positively correlated with disease duration, transfusion index, white blood cell count, HbS, markers of hemolysis, serum ferritin, D-dimer, and vWF Ag, whereas negatively correlated with hemoglobin and HbF levels (p < 0.05). Both PMPs and ErMPs levels were positively correlated with aortic stiffness, pulmonary artery pressure, and tricuspid regurgitant velocity (p < 0.05) while negatively correlated with aortic distensibility. We suggest that PMPs and ErMPs overproduction may be considered a potential biological marker for vascular dysfunction and disease severity in SCD and may be implicated in the pathogenesis of coagulation abnormalities encountered in those patients. Their levels are closely related to sickling crisis, pulmonary hypertension, markers of hemolysis, fibrinolysis, and iron overload. Therefore, quantification of MPs in SCD may provide utility for identifying patients who are at increased risk of thrombotic events or cardiovascular abnormalities and would help to monitor response to hydroxyurea therapy.

Flow cytometric assessment of circulating platelet and erythrocytes microparticles in young thalassemia major patients: relation to pulmonary hypertension and aortic wall stiffness.

Heart disease is the leading cause of mortality and morbidity in β‐thalassemia major (β‐TM). Aggregability of abnormal red cells and membrane‐derived microparticles (MPs) stemming from activated platelets and erythrocytes are responsible for thrombotic risk. We measured platelet and erythrocyte MPs (PMPs and ErMPs) in 60 young β‐TM patients compared with 40 age‐ and sex‐matched healthy controls and assessed their relation to clinicopathological characteristics and aortic elastic properties. Patients were studied stressing on transfusion history, splenectomy, thrombotic events, chelation therapy, hematological and coagulation profiles, flow cytometric measurement of PMPs (CD41b+) and ErMPs (glycophorin A+) as well as echocardiographic assessment of aortic elastic properties. Aortic stiffness index and pulmonary artery pressure were significantly higher, whereas aortic strain and distensibility were lower in TM patients than controls (P < 0.001). Both PMPs and ErMPs were significantly elevated in TM patients compared with controls, particularly patients with risk of pulmonary hypertension, history of thrombosis, splenectomy or serum ferritin >2500 μg/L (P < 0.001). Compliant patients on chelation therapy had lower MPs levels than non‐compliant patients (P < 0.001). PMPs and ErMPs were positively correlated to markers of hemolysis, serum ferritin, D‐dimer, vWF Ag, and aortic stiffness, whereas negatively correlated to hemoglobin level and aortic distensibility (P < 0.05). We suggest that increased MPs may be implicated in vascular dysfunction, pulmonary hypertension risk, and aortic wall stiffness observed in thalassemia patients. Their quantification could provide utility for early detection of cardiovascular abnormalities and monitoring the biological efficacy of chelation therapy.

Romiplostim therapy in children with unresponsive chronic immune thrombocytopenia

Romiplostim, a thrombopoiesis-stimulating peptibody, represents a new therapeutic option in adult refractory chronic immune thrombocytopenia (ITP). This study aimed to assess the short-term efficacy and safety of romiplostim in children with chronic ITP. Eight non-splenectomized patients with chronic ITP refractory to standard lines of medical therapy were recruited from the Pediatric Hematology Unit, Childrens Hospital, Ain Shams University, Cairo, Egypt. One patient was initially excluded because of increased bone marrow reticulin (grade 3). Therapy was initiated in seven patients, aged 3.4–15.2 years (median 5.5 years), and the disease duration ranged from 13 months to 7.3 years (median 2.4 years); none were splenectomized. Romiplostim dose was started as 1 µgm/kg/week and the dose escalated by 1 µgm/kg/week according to platelet count. The duration of therapy varied between 1 and 22 weeks (median 12 weeks). Results revealed that four out of the seven patients achieved variable response. Four patients demonstrated rapid increase in platelet count when pulse steroid therapy was added. Most reported adverse events were mild and transient. This case series study reveals variable response rate in children with chronic ITP to romiplostim therapy; addition of steroids especially in emergency bleeding situations could potentiate romiplostim thrombopoietic effect even in patients initially refractory to steroids. Romiplostim safety and efficacy in pediatric ITP needs further long-term studies.

Subclinical atherosclerosis in young beta-thalassemia major patients.

Subclinical atherosclerosis in young β-thalassemia major (β-TM) patients and its risk factors including dyslipidemia compared to type 1 diabetic patients were assessed. Ninety subjects were included and divided into three groups: group I comprised 30 β-TM patients with a mean age of 18.4 ± 6.18 years; group II comprised of 30 type 1 diabetic patients with a mean age of 19.23 ± 4.25 years, and 30 healthy subjects served as controls in group III. Fasting lipid profiles, hemoglobin (Hb) electrophoresis, serum ferritin and high resolution ultrasound for the measurement of carotid artery intima media thickness (CIMT) were done. Serum triglycerides, total cholesterol, apoprotein A (ApoA), and CIMT were significantly elevated, while high density lipoproteins (HDL) were significantly lowered in thalassemic and diabetic patients compared to controls. In thalassemic patients, CIMT was positively correlated with age, Hb F, ferritin and cholesterol levels. Atherogenic lipid profiles in young thalassemic patients with increased CIMT highlights their importance as prognostic factors for vascular risk stratification.

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.

Health-Related Quality of Life in Egyptian Children and Adolescents with Hemophilia A

Quality of life (QoL) in hemophilia is an important area in hemophilia outcome assessment. The Haemo-QoL instrument is a set of questionnaires to measure QoL in those children. The objectives of this study was to assess health-related quality of life (HRQoL) in Egyptian hemophilic children and adolescents using an Arabic version of the Haemo-QoL questionnaire. Sixty patients with severe hemophilia A were recruited from 2 hemophilia treating centers in Egypt. Assessment of quality of life was done using the Haemo-QoL questionnaire. The scores of HRQoL were found to be for all dimensions widely above 50. It was highly significant in the 3 dimensions (physical health–family–treatment) in different age groups, but it was impaired in the dimension of “physical health” for 2 groups, and in the dimension of “family” for the oldest group, whereas the youngest group had highly impaired scores concerning the “treatment.” The HRQoL in this study was not affected by the presence of factor VIII (FVIII) inhibitors. The QoL in hemophilic patients in Egypt needs strenuous efforts from hemophilia care–integrated teams of pediatric hematologists and psychiatrists in order to properly assess and improve QoL.

Pulmonary Complications in Survivors of Childhood Hematological Malignancies: Single-Center Experience

Children treated for cancer face the risk of complications later in life, including pulmonary dysfunction. The objective of this study was to evaluate frequency and severity of pulmonary complications in survivors of childhood leukemia and lymphoma treated with chemotherapy alone or combined with radiotherapy. Seventy cancer survivors of hematological malignancies were evaluated for pulmonary complications through history taking, chest examination, high-resolution computed tomography (HRCT) chest, and pulmonary function testing (PFTs). Although most survivors were not clinically compromised, the spectrum of impaired PFTs included obstructive pattern (14.3%), restrictive pattern (5.7%), and mixed pattern (20%). Significant pulmonary dysfunction was seen in children older than 10 years of age (P = .003), and in patients treated with combined chemotherapy and radiotherapy (72.7%) compared with those treated with chemotherapy alone (25%) (P = .001). Cumulative dose of bleomycin was significantly associated with abnormal PFTs (P = .04). Multivariate analysis revealed methotrexate therapy as significant predictor of abnormal PFTs (P = .002). Male patients who received combined therapy showed higher frequency of restrictive, obstructive lung disease, abnormal respiratory reactance, and peripheral airway disease (P = .007, P = .04, P = .002, P = .003, P = .05, respectively). Those with abnormal CT findings (n = 14) had lower forced vital capacity (FVC%), forced expiratory volume in 1 second (FEV1%), and peak expiratory flow (PEF%) when compared to cases with normal CT (P = .001, P <0.001, P = .001, respectively). Subclinical pulmonary function abnormalities are found in survivors of childhood hematological malignancies previously treated and off therapy. Pulmonary dysfunction is more evident with combined chemotherapy and radiotherapy, bleomycin, and methotrexate are the most incriminated chemotherapeutic agents, and males are at higher risk than females; therefore a specific and extended follow-up is warranted.

Clinicopathological and radiological study of Egyptian β-thalassemia intermedia and β-thalassemia major patients: relation to complications and response to therapy.

The clinico epidemiological characteristics, frequency of complications, and response to various therapeutic modalities in 80 Egyptian β-thalassemia intermedia (β-TI) patients were compared with 70 β-thalassemia major (β-TM) patients. β-Thalassemia intermedia patients had a higher incidence of left atrium dilatation, right ventricular dilatation and pulmonary hypertension, whereas, β-TM patients showed a higher incidence of left ventricular (LV) dilatation, restrictive LV filling and impaired LV contractility, with an overall higher incidence of heart disease (p <0.001). Short stature, delayed puberty, osteoporosis, bone fractures, diabetes mellitus and viral hepatitis was frequently observed in β-TM patients compared with β-TI patients (p <0.05). Administration of hydroxyurea (HU) alone was associated with significant improvement in hematological parameters and quality of life for β-TI patients. In conclusion, the risk of complications still burdens the life of Egyptian thalassemia patients and their frequency varies between β-TI and β-TM. We provide evidence that calls for the use of HU in β-TI patients.

Endothelial nitric oxide synthase gene intron 4 VNTR polymorphism in sickle cell disease: Relation to vasculopathy and disease severity

Impaired NO bioavailability represents the central feature of endothelial dysfunction, and is a common denominator in the pathogenesis of vasculopathy in sickle cell disease (SCD). Evidence indicates the contribution of 4a allele of endothelial NO synthase (eNOS) gene to cardiac and renal diseases. We studied the 27‐base pair tandem repeat polymorphism in intron 4 of eNOS gene in 51 patients with SCD compared with 55 healthy controls and evaluated its role in disease severity and hemolysis‐associated complications.