Maria Altomare

Metabolic, inflammatory, endothelial and haemostatic markers in a group of Italian obese children and adolescents.

Childhood obesity and its related comorbidities are increasingly recognised in children, predisposing them to early cardiovascular disease and metabolic syndrome. The objective of the study was to investigate markers of metabolism, inflammation and haemostasis in a group of Italian obese children and adolescents. Fifty-nine obese and 40 non-obese subjects were recruited. Fasting glucose and insulin, total cholesterol, HDL and LDL cholesterol, triglycerides, high-sensitivity C-reactive protein (hsCRP), tumour necrosis factor alpha (TNF-α), and adiponectin were measured. Hypercoagulability was assessed by measuring the circulating levels of thrombin-antithrombin complex (TAT), D-dimer, fibrinogen, plasminogen activator inhibitor 1 (PAI-1) and von Willebrand Factor (vWF). A significant degree of insulin resistance was present in obese subjects compared with controls (p < 0.0001). The obese showed higher levels of total cholesterol, LDL cholesterol and triglycerides, and lower levels of HDL cholesterol than controls (p < 0.0001). Circulating levels of hsCRP and TNF-α were significantly higher in obese than in controls while serum adiponectin levels were significantly lower in obese than non-obese subjects (p < 0.001; p = 0.031; p < 0.0001, respectively). vWF, TAT, D-dimer, fibrinogen and PAI-1 levels were significant higher in obese subjects compared with control group (p = 0.02; p < 0.0001; p = 0.0037; p < 0.0001; p = 0.017, respectively). In conclusion, our results suggest that childhood obesity per se is associated with a proinflammatory and prothrombotic state.

Lupus anticoagulant, anticardiolipin antibodies and hepatitis C virus infection in thalassaemia

Anticardiolipin antibodies (ACA) and lupus anticoagulant (LA) have been detected in patients with hepatitis C virus (HCV) infection and have been associated in autoimmune diseases (i.e. systemic lupus erythematosus) with an increased risk of thromboembolic events. Because of the high prevalence of HCV infection and the thrombotic risk described in thalassaemia we decided to investigate the prevalence of ACA and LA in a cohort of 68 thalassaemia patients. We found a high prevalence (34%) of β2‐glycoprotein I independent ACA in our thalassaemia patients which was related to HCV infection. None of patients developed any complications related to antiphospholipid antibodies (APL); therefore the clinical significance of positivity for APL in patients with HCV infection is at present unclear. In conclusion, the results of our study indicate that ACA in the serum of HCV‐infected thalassaemic patients exhibit the characteristics of natural autoantibodies rather than those of the pathogenic autoantibodies that are found in patients with systemic lupus erythematosus.

Prospective study of hemostatic alterations in children with acute lymphoblastic leukemia

In a group of newly diagnosed acute lymphocytic leukemia (ALL) children we evaluated a number of hemostatic and inflammatory markers at diagnosis and at different time points during chemotherapy for the remission induction to identify alterations in the plasma levels of prothrombotic markers before and during the course of chemotherapy. The following plasma markers were evaluated: thrombin‐antithrombin complex (TAT), D‐Dimer, plasminogen activator inhibitor 1 (PAI‐1), antithrombin, fibrinogen, von Willebrand factor (VWF) antigen and high molecular weight VWF (HMW‐VWF) multimers, P‐selectin, tumor necrosis factor alpha (TNF‐α), and interleukin 6 (IL‐6). Plasma samples were collected at the following time points: at T0 (baseline) and T1 (+24 days of therapy), T2 (+36 days therapy), and T3 (+64 days therapy). The results show that, at diagnosis, ALL children presented with laboratory signs of increased thrombin generation and fibrin formation (i.e. high TAT and D‐dimer levels), fibrinolysis inhibition (i.e. high PAI‐1 level), endothelial activation (i.e., high HMW‐VWF and soluble P‐selectin levels) and inflammation (i.e. high TNF‐alpha and IL‐6 levels). After starting induction therapy, the thrombin generation markers and inflammatory cytokines significantly decreased. To the opposite, PAI‐1 and P‐selectin significantly increased, suggesting an insult by chemotherapy on the vascular endothelium. These effects were more evident during steroid administration. Symptomatic venous thromboembolism (VTE) episodes developed in two cases during induction therapy, which did not allow the evaluation of the predictive value for VTE of laboratory markers. Am. J. Hematol., 2010.

von Willebrand factor and factor XIII in children with Henoch-Schonlein purpura.

Levels of von Willebrand factor antigen (vWf: Ag) and factor XIII activity (F XIII) were studied in relation to the severity of clinical symptoms (scored from 0 to 3) and to immunological parameters [IgA, C3, C4, and circulating immune complexes (CIC) in 16 children (7 males, 9 females, aged 3–11 years) with Henoch-Schonlein purpura (HSP) at presentation. vWf: Ag was increased in 7 patients, F XIII activity was decreased in 6. In all children we found high levels of IgA, while C3 and C4 levels were normal; CIC were elevated in 11. vWf: Ag correlated with clinical score and with IgA and CIC, probably as a result of immune-mediated endothelial cell damage. The haemostatic alterations observed in HSP are important for understanding the pathophysiology of the disease.

Calprotectin levels in meconium.

Aim: To evaluate the effect of gender, gestational age, birthweight, mode of delivery, 5′‐Apgar score and maternal conditions on calprotectin concentrations in meconium. Methods: Calprotectin was measured in 131 neonates, in the first passed meconium. Results: Calprotectin levels (mean ± SD) resulted in 145.2 ± 78.5 mg kg−1 meconium, significantly correlated with birthweight (r=–0.333; p < 0.001), gestational age (r =–0.206; p = 0.018) and 5′‐Apgar score (r= ‐0.243, p= 0.035). The estimated regression model was: calprotectin levels (mg kg−1) = 269.58–41.54 weight (kg); r = 0.383, p < 0.001. No differences were found in relation to gender, mode of delivery and maternal conditions.

Coagulation and fibrinolytic systems in the ill preterm newborn

Aim: The activation pattern of the clotting and fibrinolytic systems in 63 preterm infants (GA 31, 6 ± 2.3 weeks) was studied. Methods: The infants were divided into four groups: (i) IRDS, (ii) asphyxia at birth, (iii) sepsis, and (iv) mild infection. A control group was composed of preterm infants without any apparent disease (GA 32 ± 1.8 weeks). Results: During IRDS we found a systemic activation of both coagulation and fibrinolysis at birth which was represented by lower levels of ATIII (27.7 ± 8.8%) and significantly greater levels of TAT (37.9 ± 31.9 ng/ml), D‐dimers (1242.7 ± 206.9 ng/ml), tPA Ag (10.9 ± 5.3 ng/ml) and PAI Ag (59.9 ± 16.7 ng/ml) than in the control group. In the asphyxiated newborns there were no significant differences from the controls. During their seventh day of life, a significant reduction of all the analysed parameters (TAT, D‐dimers, tPA, PAI) and a significant increase in ATIII were seen in the newborns with IRDS, while no significant modification was observed in the newborns with asphyxia at birth. When the newborns with sepsis were compared with those with mild infection, their TAT and PAI values proved to be significantly higher for the first tests (21.7 ± 18.8 vs 9.2 ± 6.9 μgA and 53.6 ± 14.4 vs 37.7 ± 10.2 ng/ml respectively). During the second tests, 7 days later, only TAT (16.7 ± 14.7 vs 6.3 ± 4 jtg/1) levels remained high while D‐dimers (1094.2 ± 400.6 vs 646 ± 200 ng/ml) and tPA (11.3 ± 8 vs 4.9 ± 2 ng/ml) were significantly higher in the septic group of newborns than those with mild infection. Conclusions: These data indicate that there is an activation of the clotting and fibrinolytic systems both in the initial phase of IRDS as well as during sepsis.

THROMBIN GENERATION IN CHILDREN WITH ACUTE LYMPHOBLASTIC LEUKEMIA: Effect of Leukemia Immunophenotypic Subgroups

Elevated plasma concentrations of endogenous thrombin generation markers and thrombotic events have been reported in children with leukemia. The aim of this study was to evaluate the effects of cancer and its treatment on thrombin generation (TAT levels) in children with acute lymphoblastic leukemia (ALL). The authors evaluated 32 children (23 M, 9 F) aged between 1 and 15 years (mean 6) affected by ALL (immunophenotypic subgroups: 16 common, 7 T, and 9 pre-B type). In all patients TAT levels at onset and after 5-6 doses of L-asparaginase were evaluated. TAT levels were higher in patients both at onset (13.04 +/- 10.90 ng/L) and after the 5-6 doses of L-asp (19.41 +/- 11.05 ng/L) with respect to controls (4 +/- 1 ng/L) (p < .001 and p < .001). TAT levels after 5-6 doses of L-asp were higher than those at onset (p < .001). Factorial ANOVA showed that at onset there was a significant effect of leukemia immunophenotypic subgroups upon TAT levels (p < .05) and no effect of inherited thrombotic risk factors. These results indicate that in children with ALL an important role is played by acquired thrombotic risk factors, among which the indirect cancer procoagulant activity has its importance.

Does Calprotectin Represent a Regulatory Factor in Host Defense or a Drug Target in Inflammatory Disease

Calprotectin, a protein composed by two subunits of 8 and 14 kD respectively, is released by neutrophils in the biological fluids under inflammatory states. For instance, detection of calprotectin in faeces represents a diagnostic tool in the case of inflammatory bowel disease. Quite interestingly, calprotectin is increased in the stool of healthy newborns from day three up to day thirty and, physiologically, this increase may be interpreted as a defense mechanism against yeast and fungi. Therapeutic attempts at inhibiting the deleterious effect of calprotectin have been experimentally made by using lycoricinidol. This natural compound is able to hamper the calprotectin-induced apoptosis on the one hand. On the other hand, the same compound plays a prophylactic role in the course of experimental arthritis in rats.

Familial Dominant Thrombocytopenia: Clinical, Biologic, and Molecular Studies

Inherited thrombocytopenias are a heterogenous group of disorders. Different criteria have been suggested to classify the forms, such as the inheritance mechanism and the platelet volume as well as the number and morphology of megakaryocytes. However, the classification is often descriptive, and the precise mechanism of thrombocytopenia still remains unknown. We describe the clinical, biologic, and molecular findings of an autosomal dominant thrombocytopenia in a large family. The 17 patients had normocellular bone marrow and normal platelet volume. Platelets also showed a normal aggregation test and normal response to ADP and thrombopoietin (TPO). In the affected subjects, the mean ± SD levels of platelet count and plasma TPO were 62 ± 25 and 258 ± 151, respectively. Comparative analysis showed that the patients with platelet count <70 000 had higher plasma TPO concentration. The data are consistent with a mild clinical form of the disease associated with only a few episodes of bleeding. To exclude the possible role of TPO and its receptor c-mpl in the etiology of this condition, linkage analysis was performed using microsatellite markers close to the TPO and c-mpl genes on chromosomes 3q26.3-q27 and 1p34, respectively. The absence of cosegregation within the affected family indicated that these genes, as well as two other candidate loci on chromosomes 11 and 21, are not responsible for this hereditary dominant form of thrombocytopenia. A genome-wide search and subsequent identification of the gene will provide new insight into the pathogenesis of this disorder.

Clinical significance of serum cytokine levels and thrombopoietic markers in childhood idiopathic thrombocytopenic purpura.

BACKGROUND Biological markers useful for defining children with newly diagnosed immune thrombocytopenic purpura (ITP) who are likely to develop the chronic form of the disease are partially lacking. The purpose of this study was to assess the clinical role of both immunological and thrombopoietic markers in children with ITP and correlate their levels with different disease stages. MATERIALS AND METHODS We enrolled 28 children with ITP at the onset of their disease, who were followed-up for a whole year and divided according to whether their disease resolved within the 12 months (n=13) or became chronic (n=15), 11 subjects with chronic ITP off therapy for at least 1 month at the time of enrolment, and 30 healthy matched controls. Serum levels of T helper type 1 and 2 and T regulatory-associated cytokines, such as interferon γ, tumour necrosis factor α, interleukin (IL) 2, IL6, IL10, and thrombopoietin were measured in all children using quantitative immunoenzymatic assays, while reticulated platelets were evaluated by flow cytometric analysis. RESULTS Serum IL10 levels were significantly higher in patients with an acute evolution of ITP than in either healthy controls (p<0.001) or patients with chronic progression of ITP (p<0.05). Reticulated platelet count and thrombopoietin levels were significantly higher in ITP patients at the onset of their disease, whether with acute resolution or chronic progression, than in healthy subjects (p<0.01; p<0.001), but did not differ between the groups of patients. CONCLUSION IL-10 seems to predict the clinical course of ITP, as it is significantly higher at the onset of disease in patients who obtain disease remission in less than 1 year.