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Asparaginase is essential in the treatment of lymphoproliferative malignancies, but it is associated with several side effects. The objective of this study was to compare asparaginase-induced alterations of the coagulation inhibitors and the impact on central line-associated thrombosis in children treated according to 2 different asparaginase regimens. The study enrolled 30 children treated for acute lymphoblastic leukemia, and they were divided into 2 groups with respect to asparaginase preparation and protocol (NOPHO ALL-1992 versus NOPHO ALL-2000). The coagulation inhibitors antithrombin, protein C, and proteins S were measured prior to and during asparaginase therapy, and incidence of central line-associated thromboses was compared to evaluate the protocols' thrombogenicity. Thirteen children received Erwinia asparaginase and 17 children received E. coli asparaginase. Independent of protocol, the coagulation inhibitors were significantly reduced during asparaginase therapy (p < .001), and central line-associated thromboses were frequent. Four children developed thrombosis in the course of asparaginase therapy, and there was a correlation between asparaginase-induced fall of antithrombin and occurrence of new thromboses (p = .01).

Thrombophilia screening is a time-consuming and expensive procedure. Information about thromboembolism among relatives may be a simple method to identify those at risk of having thrombophilia. In a cross-sectional clinical study the authors have investigated the role of such family histories to detect children with thrombophilia. In 202 children a family history of venous or arterial thromboembolism was recorded. The participants were either children with congenital heart defects at the time of a scheduled cardiac catheterization (n=134) or children with newly diagnosed cancer (n=68). Questions were answered, on the spot, by the parents, at the same time as blood samples for thrombophilia screening were taken. Questions about family history of thromboembolism were completed in 184 children, of whom 114 children (62%) were positive, and 35 of these had relatives with venous thromboembolic events. Only one child had an affected first-degree relative. Thrombophilic alterations were observed in 60 children (30%), and 25 of these were defined as inherited. A positive family history of venous origin increased the relative risk of a child having inherited thrombophilia to 2.35 (95% confidence interval 1.1--5.2). Information about familial arterial thromboembolism was not useful in spotting children with prothrombotic risk factors. These results indicate that questioning about family history of venous thromboembolism may identify children with genetic thrombophilia, but the association is not strong. The authors encourage similar larger-scale studies to enlighten the issue fully.

A prospective, population-based registration of children with immune thrombocytopenic purpura (ITP) was performed in Norway in 1996 and 1997. Ninety-two cases were identified, indicating an incidence of 5.3 per 100,000 children under 15 years. The sex ratio (female/male) was 1.2/1. Fifty-six percent presented with cutaneous signs only. The lowest platelet count was < 20 x 10(9)/L in 91%. In spite of mild bleeding symptoms, medical treatment was given in 68%, in most cases (57/63) with intravenous immunoglobulin. A total of 41/44 patients with platelet counts of < or = 5 x 10(9)/L were treated, regardless of whether they had mucous bleedings or not. Eighteen percent had platelet counts < 150 x 10(9)/L at 6 months, and 9% at 12 months following diagnosis. One patient with therapy-resistant chronic ITP died 16 months after diagnosis from an anesthesia complication related to profound epistaxis. This study shows a relatively high incidence. As in other studies, there was a tendency to treat platelet counts rather than bleeding symptoms.

Sixty-one children were examined for thyroid dysfunction as an adverse late effect after cessation of antileukemic treatment. The aim of the study was to contribute to clarifying which types of therapy can cause this endocrine disorder. Our treatment protocols do not include cranial irradiation as CNS prophylaxis, but we give relatively intensive intrathecal methotrexate treatment. The results indicate that this cytostatic regimen alone does not cause thyroid dysfunction as an adverse late effect.

Nineteen children treated for Wilms' tumor (thirteen cases) or Hodgkin's disease (six cases) with cytostatic agents and/or radiotherapy were studied cytogenetically on lymphocytes cultivated from blood samples drawn after at least 1 year of complete remission after end of therapy. A reference group of children was matched for age, sex, and residence. The frequencies of sister chromatid exchange (5.4 versus 5.6 SCE/cell), and chromosome damage type gaps (6.6 versus 7.1%) and breaks (1.9 versus 1.9%) were not different in the two groups, but exchange type aberrations were more frequent in the patients (0.9 versus 0.06%). Fifty karyotypes were analyzed in all but two cases of Hodgkin's disease. The overall frequency of stable (3.1 versus 3.8%) and unstable (1.7 versus 1.4%) structural chromosome changes such as translocations, deletions, chromatid exchanges, and dicentrics were not different in the patient and the control groups. If the chromosome data reflect a general cancer risk, this risk cannot be considerably higher among the cancer-treated children.