The incidence of thrombosis is higher among newborn infants than in any other stage of pediatric development. This fact is the consequence of labile characteristics of the neonatal hemostatic system, in addition to exposure to multiple risk factors and the wide use of vascular catheters. Venous thromboses, which mainly affect the limbs, the right atrium and renal veins, are more frequently seen than arterial thromboses. A stroke may be caused by the occlusion of the arterial flow entering the brain or by occlusion of its venous drainage system. Purpura fulminans is a very severe condition that should be treated as a medical emergency, and is secondary to severe protein C deficiency or, less frequently, protein S or antithrombin deficiency. Most thrombotic events should be managed with antithrombotic therapy, which is done with unfractionated and/or low molecular weight heparins. Purpura fulminans requires protein C replacement and/or fresh frozen plasma infusion. Thrombolytic therapy is done using tissue plasminogen activator and should only be used for life-, or limb-, or organthreatening thrombosis.
The impaired hematopoiesis in acquired aplastic anemia (AA) results from immune-mediated mechanisms. We characterized polymorphisms implicated in controlling type-1 cytokine production in 69 patients with AA. Our data suggest that the studied polymorphisms are not associated with susceptibility in the overall AA population. However, the presence of the higher expressing TNF - 308A allele was associated with younger age (p = 0.0297) and more profound neutropenia (p = 0.0312), and over-represented in patients with very severe AA (p = 0.0168). The higher producing IFNG 12 CA-repeat allele showed strong linkage disequilibrium with the + 874T allele, and was associated with a lower hemoglobin level (p = 0.0351). Also, the presence of at least one higher expressing variant was more frequent among patients responding to immunosuppressive treatment (p = 0.0519). Our findings suggest that the presence of higher expressing variants of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in AA patient genotypes could be related to clinical parameters, disease severity and therapy outcomes.
Two distinct syndromes that link α-thalassemia and intellectual disability (ID) have been described: ATR-X, due to mutations in the ATRX gene, and ATR-16, a contiguous gene deletion syndrome in the telomeric region of the short arm of chromosome 16. A critical region where the candidate genes for the ID map has been established. In a pediatric patient with Hemoglobin H disease, dysmorphic features and ID, 4 novel and clinically relevant Copy Number Variants were identified. PCR-GAP, MLPA and FISH analyses established the cause of the α-thalassemia. SNP-array analysis revealed the presence of 4 altered loci: 3 deletions (arr[hg19]Chr16(16p13.3; 88,165-1,507,988) x1; arr[hg19]Chr6(6p21.1; 44,798,701-45,334,537) x1 and arr[hg19]Chr17(17q25.3; 80,544,855-81,057,996) x1) and a terminal duplication (arr[hg19]Chr7(7p22.3-p22.2; 4,935-4,139,785) x3). The -α(3.7) mutation and the ∼1.51 Mb in 16p13.3 are involved in the alpha-thalassemic phenotype. However, the critical region for ATR-16 cannot be narrowed down. The deletion affecting 6p21.1 removes the first 2 exons and part of intron 2 of the RUNX2 gene. Although heterozygous loss of function mutations affecting this gene have been associated with cleidocranial dysplasia, the patient does not exhibit pathognomonic signs of this syndrome, possibly due to the fact that the isoform d of the transcription factor remains unaffected. This work highlights the importance of searching for cryptic deletions in patients with ID and reiterates the need of the molecular analysis when it is associated to microcytic hypochromic anemia with normal iron status.
The cover image, by Karen G. Scheps et al., is based on the Research Article Multiple copy number variants in a pediatric patient with Hb H disease and intellectual disability, DOI: .
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.