Vitamin D Insufficiency Is Common in Ugandan Children and Is Associated with Severe Malaria

Vitamin D plays an increasingly recognized role in the innate and adaptive immune response to infection. Based on demonstrated roles in up-regulating innate immunity, decreasing inflammation, and reducing the severity of disease in illnesses such as tuberculosis and influenza, we hypothesized that poor vitamin D status would be associated with severe malaria. We measured 25-hydroxyvitamin D [25(OH)D] by immunoassay in a sample of Ugandan children aged 18 months-12 years with severe malaria (cerebral malaria or severe malarial anemia, n = 40) and in healthy community children (n = 20). Ninety-five percent of children with severe malaria (n = 38) and 80% of control children (n = 16) were vitamin D-insufficient [plasma 25(OH)D <30 ng/mL]. Mean plasma 25(OH)D levels were significantly lower in children with severe malaria than in community children (21.2 vs. 25.3 ng/mL, p = 0.03). Logistic regression revealed that for every 1 ng/mL increase in plasma 25(OH)D, the odds of having severe malaria declined by 9% [OR = 0.91 (95% CI: 0.84, 1.0)]. These preliminary results suggest that vitamin D insufficiency may play a role in the development of severe malaria. Further prospective studies in larger cohorts are indicated to confirm the relationship of vitamin D levels to severity of malaria infection and to investigate causality

Preanalytical Issues in Hemostasis and Thrombosis Testing

Hemostasis testing is critical to many hemorrhagic and thrombotic disorders, wherein laboratory diagnostics can provide critical information for diagnosis, prognostication, and therapeutic monitoring. Due to this crucial role in modern medicine, hemostasis tests should be carried out at their highest degree of quality, thus encompassing standardization and monitoring of all phases of the testing process. It is now clearly established that the preanalytical phase is the most critical and vulnerable part of the total testing process, since up to 70% of diagnostic errors are due to highly manual activities encompassing patient preparation and collection of biological samples, as well as handling, transportation, preparation and storage of blood specimens. Due to the peculiar sample matrix required for hemostasis testing (i.e., plasma anticoagulated with buffered sodium citrate), additional critical issues may impair the reliability of these tests. Therefore, this article aims to provide an updated overview of the most important preanalytical variables that may ultimately impair the quality of hemostasis and thrombosis testing

Post-analytical Issues in Hemostasis and Thrombosis Testing

Analytical concerns within hemostasis and thrombosis testing are continuously decreasing. This is essentially attributable to modern instrumentation, improvements in test performance and reliability, as well as the application of appropriate internal quality control and external quality assurance measures. Pre-analytical issues are also being dealt with in some newer instrumentation, which are able to detect hemolysis, icteria and lipemia, and, in some cases, other issues related to sample collection such as tube under-filling. Post-analytical issues are generally related to appropriate reporting and interpretation of test results, and these are the focus of the current overview, which provides a brief description of these events, as well as guidance for their prevention or minimization. In particular, we propose several strategies for improved post-analytical reporting of hemostasis assays and advise that this may provide the final opportunity to prevent serious clinical errors in diagnosis