Thrombomodulin and von Willebrand factor: relation to endothelial dysfunction and disease outcome in children with acute lymphoblastic leukemia.

The severe endothelial dysfunction in children with acute lymphoblastic leukemia (ALL) can result from the disease itself, from treatment, or from other conditions (e.g. sepsis). The aim of this study was to determine the levels of markers of endothelial activation in children with ALL and to assess their potential prognostic value. Fifty-two children with ALL, 19 children with ALL 1-10 years after the completion of therapy, and 28 healthy children were studied. In children with ALL, there was a significant increase in thrombomodulin (TM) and von Willebrand factor (vWF) levels during the acute phase of the disease and during treatment. Children with an unfavorable outcome had higher levels of TM. In conclusion, severe endothelial dysfunction is present during the acute phase of ALL and during treatment and appears to result from the disease itself. Serum TM and vWF levels might represent additional, but not independent, prognostic markers in childhood ALL.

Standard-dose intravenous anti-D immunoglobulin versus intravenous immunoglobulin in the treatment of newly diagnosed childhood primary immune thrombocytopenia.

BACKGROUND: We conducted a study to evaluate the efficacy of intravenous (IV) anti-D against IV immunoglobulin (IVIG) in newly diagnosed immune thrombocytopenia (ITP) in children and to identify the clinical characteristics of the children most likely to benefit from one or the other treatment. PROCEDURE: Children (6 mo to 14 y) with newly diagnosed ITP and a platelet count <20,000/µL were treated either with a single bolus dose of 50 µg/kg IV anti-D or with 0.8 to 1 g/kg IVIG in a randomized manner. RESULTS: Twenty-five patients, mean age of 6.8 years, were treated either with IV anti-D (n=10) or with IVIG (n=15). Both drugs were equally efficient in raising the platelet count above 20,000/µL at 24 hours posttreatment. Children who presented with bleeding stage 1 or 2 (no mucosal bleeding) responded better to IVIG treatment, in terms of an increase in platelet count at 24 hours posttreatment (P=0.04). Hemoglobin drop was greater in the anti-D group (P=0.002). CONCLUSIONS: A single bolus dose of 50 µg/kg of IV anti-D is a safe and effective first-line treatment in newly diagnosed ITP in childhood and mucosal bleeding is a poor prognostic factor for treatment with IVIG.

Candidemia complicating biliary atresia in an infant with hemoglobinopathy.

Both biliary atresia and hemoglobinopathies have been associated with a higher incidence of bloodstream infections. We hereby present the case of a female infant of Nigerian descent with extrahepatic biliary atresia and double heterozygocity for sickle cell disease and alpha-thalassemia. Kasai hepatoportoenterostomy was performed in the child's sixth week of life. Bloodstream infections occurred two months post-hepatoportoenterostomy, even though the infant was still in prophylactic antibiotic treatment: the first was due to Candida albicans and was followed by bacteremia due to Escherichia coli. A third infection, confined to the skin only, was due to Acinetobacter spp. Treatment options, predisposing factors, and the pathophysiology of bloodstream infections in patients with biliary atresia and aberrant hemoglobin are discussed herein.

Hem biliyer atrezi, hem de hemoglobinopatilerde, kan dolasimi enfeksiyonu sikligi daha fazladir. Burada, ekstrahepatik biliyer atrezisi ve "sickle-cell" hastaligi ve alfa-talasemi için çift heterozigot olan Nijerya kökenli bir kiz bebegi sunuyoruz. Çocuga yasaminin altinci haftasinda Kasai hepatoportoenterostomi uygulandi. Halen profilaktik antibiyotik tedavisi almakta olmasina ragmen, hepatoportoenterostomiden iki ay sonra kan dolasimi enfeksiyonlari ortaya çikmistir: birincisi kandida albikansa bagli iken, bunu Escherichia coli'e bagli bakteriyemi izlemistir. Sadece cilt ile sinirli kalan üçüncü bir enfeksiyon Acinetobacter spp'e bagli olarak gelismistir. Bu yazida biliyer atrezi ve anormal hemoglobini olan hastalarda, tedavi seçenekleri, predispozan faktörler ve kan dolasimi enfeksiyonlarinin patofizyolojisi tartisilmistir.

Tibial pseudotumor in a child with hemophilia.

Hemophilic pseudotumor is an uncommon complication seen in approximately 1-2% of patients with severe hemophilia. Hemophilic pseudotumors are distinguished into two subdivisions based on location, proximal or distal. Plain x-rays and CT are useful in diagnosis, but MR imaging is the diagnostic test of choice because of its sensitivity to the various blood products. The choice of therapy depends on many parameters, such as the size of the tumor, the age of the patient, and the relation with underlying organs. In most cases of asymptomatic hemophilic pseudotumor, conservative treatment with administration of missing factor as well as immobilization is recommended. The authors describe a 13-year-old boy with severe hemophilia A, who presented with a tibial pseudotumor a few months after an injury. He was conservatively treated for a long period, with daily administration of recombinant factor VIII. His clinical condition improved shortly after therapy induction, but radiological improvement has been moderate. Case history, imaging findings, and therapeutic options are discussed.

Increased expression of multidrug resistance gene (MDR1) at relapse in a child with acute lymphoblastic leukemia.

Modern treatment protocols lead to complete remission in a high proportion of patients with childhood acute lymphoblastic leukemia (ALL). However, a large number of them show a relapse of the disease. Treatment failure in these patients is mainly attributable to de novo or acquired resistance to a wide variety of cytotoxic drugs, which is called multi drug resistance (MDR). Expression of multi drug resistance 1 gene (MDR1) is implicated in the drug-resistance mechanism. In order to contribute further information we present a rare case of a 15-month old girl with newly diagnosed CALLA positive pre-B acute lymphoblastic leukemia with favourable prognostic factors at diagnosis who experienced a relapse of the disease. Using reverse transcriptase polymerase chain reaction method, m-RNA expression of the MDR1 gene upon relapse, was five-fold compared with that at diagnosis. This is the first report on increased mRNA expression at relapse in a paired sample of a child with ALL in our region.

Treatment-related myelodysplastic syndrome (t-MDS)/acute myeloid leukemia (AML) in children with cancer: A single-center experience.

Treatment-related myelodysplastic syndrome (t-MDS)/acute myeloid leukemia (AML) is a devastating early or late complication of treatment for childhood cancer related with a significant morbidity and mortality. We retrospectively studied survivors of childhood cancer. Overall, 287 patients were recorded in the databases and we identified three (1.04%) with t-MDS. The primary cancer diagnoses were Langerhans cell histiocytosis (one patient) and acute lymphoblastic leukemia (ALL; two patients). The mean age of patients was 12.1 years. All patients had received systemic antifungal treatment for invasive pulmonary aspergillosis successfully treated with voriconazole and liposomal amphotericin B before diagnosis of t-MDS. Two patients (66%) remain alive after a median follow-up period of 3.5 years.

Thelarche variant in a girl with Angelman syndrome.

A case of Angelman syndrome (AS) with thelarche variant in a 4.5-year-old girl is presented. Clinical suspicion of AS was raised at the age of 15 months when she presented with mental retardation and epilepsy, absence of speech, ataxic gait with jerky movements, hyperactivity and paroxysmal episodes of laughter. Moreover, she had facial dysmorphic features such as microbrachycephaly, mid-facial hypoplasia, macrostomia and prominent mandible. Dinucleotide repeat polymorphism (DNRP) analysis, identified absence of maternal alleles at D15S543, D15S113 and GABRB3 loci, findings consistent with AS. Studies on CYP19 locus (outside the 15q11-13 region) revealed the presence of two different alleles, thus excluding the possibility of paternal isodisomy of chromosome 15 in this patient. Breast development at the age of 4.5 years, accompanied by accelerated growth velocity and bone age suggested the diagnosis of variant thelarche. This is the second case of AS with sexual precocity reported and whether this combination is a coincidence or not remains to be clarified.

Niemann-Pick type C disease associated with peripheral neuropathy.

Niemann-Pick type C disease is an autosomal-recessive, inherited neurovisceral lipid storage disorder. This disease results from either protein NPC1 or HE1 deficiency, which leads to cholesterol metabolism disturbance and is characterized by early hepatosplenomegaly and progressive ataxia, dystonia, cataplexy, dysarthria, and dementia. We describe a 3 1/2-year-old patient with Niemann-Pick type C disease, who presented with regression in both cognitive and motor domains. Almost 10 months before admission to the hospital, the child developed progressive speech and behavioral changes, as well as gait disturbances with frequent falls. The examination demonstrated hepatosplenomegaly, ataxia, and vertical gaze palsy. Nerve conduction velocities demonstrated mild demyelinating peripheral neuropathy. Bone marrow examination revealed foam cells, and cholesterol esterification studies found massive accumulation of unesterified cholesterol and very low intracellular esterification of exogenous lipoprotein-derived cholesterol. These results indicate Niemann-Pick type C disease. Peripheral neuropathy is a rare complication in patients with Niemann-Pick type C disease, which certainly contributes to their neurologic deterioration.

FcγRIIa and FcγRIIIa polymorphisms in childhood primary immune thrombocytopenia: implications for disease pathogenesis and outcome.

Primary immune thrombocytopenia (ITP) is the commonest acquired cause of bleeding in childhood. The aim of the present study was to evaluate the role of FcγRIIa and FcγRIIIa polymorphisms in the pathogenesis and therapeutic result of childhood ITP. The genotypic frequencies for two Fcγ receptor single-nucleotide polymorphisms, FcγRIIa-131 arginine (R) versus histidine (H) and FcγRIIIa-158 valine (V) versus phenylalanine (F) were examined in 53 children diagnosed with ITP. The genotype frequencies were compared with those of 45 healthy controls. The association between the above frequencies and disease natural course as well as therapeutic result following intravenous immunoglobulin (IVIG) administration was investigated. FcγRIIIa-158V was significantly overrepresented in children with ITP versus controls (P = 0.029), whereas no statistically significant difference was noted in FcγRIIa polymorphism distribution. No statistically significant difference was noted in the above genotype frequencies' distribution between children with newly diagnosed and chronic ITP, as well as with regards to the therapeutic result following IVIG administration. High-affinity FcγRIIIa variant (158 V) is possibly implicated in disease susceptibility, but neither of the two Fcγ receptor single-nucleotide polymorphisms seem to have any impact on chronicity or therapeutic effect of IVIG.

Subclinical central nervous system involvement and thrombophilic status in young thalassemia intermedia patients of Greek origin.

Beta thalassemia is known to be characterized by a hypercoagulable state, with prothrombotic factors present and thrombotic event development in a number of patients. The aim of the present study was to evaluate subclinical involvement of the central nervous system (CNS) in young patients with thalassemia intermedia, the use of nonimaging, noninvasive laboratory methods for detecting relevant abnormalities, and the frequency and possible correlation of coagulation abnormalities with CNS lesions. In this cross-sectional study, 24 young patients with thalassemia intermedia were evaluated (mean age 12 ± 4.6 years, range 4.5-20 years). Patients underwent neurological examination, inherited and acquired coagulation defect testing, as well as neurophysiologic and neuroimaging evaluation. Patients aged 6-16 also had intelligence scores measured. With regards to coagulation, a decrease in antithrombin III (ATIII), protein C and protein S activity was found in 4.1, 54.16 and 45.8% of patients, respectively. Increased D-dimers, as well as thrombin-antithrombin complex (TAT) and prothrombin fragment (F1 + 2) values were found in 12.5, 62.5 and 8.33% of patients, respectively. Heterozygosity and homozygosity for the methylenetetrahydrofolate reductase mutation was found in 45.8 and 12.5% of patients, whereas heterozygosity for factor V Leiden and G20210FII was found in 8.33 and 12.5% of patients, respectively, with increased prevalence compared to Greek population. Neuroimaging evaluation was normal in all patients. Neurophysiologic evaluation revealed abnormal findings in 33.3% of patients on electroencephalogram (EEG), 16% on brain auditory-evoked potentials (BAEPs) and 4.12% on somatosensory evoked potentials (SEPs). Visual-evoked potentials (VEPs) were normal in all patients. A statistically significant difference was found between low protein C values, as well as high platelet counts, with abnormal EEG findings (P = 0.004 and P = 0.039, respectively). Transcranial Doppler (TCD) measurements revealed increased peak systolic velocities in anterior and posterior cerebral arteries and in basilar artery in 57, 38 and 41% of patients, respectively, as compared to healthy population values. On the contrary, decreased mean velocities were found both on middle cerebral artery and pars terminalis of internal carotid examination in 28.5% of patients. Patients with pathological findings on TCD study had lower hematocrit (P = 0.049) and younger age (P = 0.001) than patients with normal measurements. With regards to intelligence scores, mean intelligence quotient (IQ) was 100 ± 19.1, with 11.7% of patients demonstrating IQ below 85. The study results confirm the early presence of hemostatic changes in patients with thalassemia intermedia. Additionally, they demonstrate subclinical CNS involvement starting at childhood. For such involvement detection, in addition to neuroimaging, neurophysiological and neuropsychological evaluation is warranted.