Acute extravascular hemolytic transfusion reaction due to anti-Kpa antibody missed by electronic crossmatch

AbstractBackgroundKpa antigen is a low incidence red blood cell antigen within the Kell system. Anti-Kpa alloantibody may be associated with acute and delayed hemolytic transfusion reactions.Case StudyWe report a case of a clinically significant acute extravascular hemolytic transfusion reaction mediated by previously unrecognized (and undetected) anti-Kpa alloantibody. This reaction occurred in a patient who met all criteria for electronic crossmatch, resulting in the transfusion of an incompatible red cell unit.ResultsPost-transfusion investigation showed the transfused red cell unit was crossmatch compatible at the immediate spin phase but was 3 + incompatible at the antiglobulin phase. No evidence of intravascular hemolysis was observed upon visual comparison of the pre- and post-transfusion peripheral blood plasma. Further testing showed the presence of anti-Kpa antibody. The clinical course of the patient included acute febrile and systemic reaction.ConclusionAcute extravascular hemolytic transfusion reaction may occur due to undetected anti-Kpa alloantibody. Various strategies for crossmatching are discussed in the context of antibodies to low incidence antigens

Reassessing the role of mitochondrial DNA mutations in autism spectrum disorder

<p>Abstract</p> <p>Background</p> <p>There is increasing evidence that impairment of mitochondrial energy metabolism plays an important role in the pathophysiology of autism spectrum disorders (ASD; OMIM number: 209850). A significant proportion of ASD cases display biochemical alterations suggestive of mitochondrial dysfunction and several studies have reported that mutations in the mitochondrial DNA (mtDNA) molecule could be involved in the disease phenotype.</p> <p>Methods</p> <p>We analysed a cohort of 148 patients with idiopathic ASD for a number of mutations proposed in the literature as pathogenic in ASD. We also carried out a case control association study for the most common European haplogroups (hgs) and their diagnostic single nucleotide polymorphisms (SNPs) by comparing cases with 753 healthy and ethnically matched controls.</p> <p>Results</p> <p>We did not find statistical support for an association between mtDNA mutations or polymorphisms and ASD.</p> <p>Conclusions</p> <p>Our results are compatible with the idea that mtDNA mutations are not a relevant cause of ASD and the frequent observation of concomitant mitochondrial dysfunction and ASD could be due to nuclear factors influencing mitochondrion functions or to a more complex interplay between the nucleus and the mitochondrion/mtDNA.</p

Blood-Feeding Induces Reversible Functional Changes in Flight Muscle Mitochondria of Aedes aegypti Mosquito

Background: Hematophagy poses a challenge to blood-feeding organisms since products of blood digestion can exert cellular deleterious effects. Mitochondria perform multiple roles in cell biology acting as the site of aerobic energytransducing pathways, and also an important source of reactive oxygen species (ROS), modulating redox metabolism. Therefore, regulation of mitochondrial function should be relevant for hematophagous arthropods. Here, we investigated the effects of blood-feeding on flight muscle (FM) mitochondria from the mosquito Aedes aegypti, a vector of dengue and yellow fever. Methodology/Principal Findings: Blood-feeding caused a reversible reduction in mitochondrial oxygen consumption, an event that was parallel to blood digestion. These changes were most intense at 24 h after blood meal (ABM), the peak of blood digestion, when oxygen consumption was inhibited by 68%. Cytochromes c and a+a3 levels and cytochrome c oxidase activity of the electron transport chain were all reduced at 24 h ABM. Ultrastructural and molecular analyses of FM revealed that mitochondria fuse upon blood meal, a condition related to reduced ROS generation. Consistently, BF induced a reversible decrease in mitochondrial H2O2 formation during blood digestion, reaching their lowest values at 24 h ABM where a reduction of 51% was observed. Conclusion: Blood-feeding triggers functional and structural changes in hematophagous insect mitochondria, which may represent an important adaptation to blood feedin

Epidemiology of hepatitis B in Canada

OBJECTIVE: To provide a current and comprehensive review of the epidemiology of hepatitis B virus (HBV) in Canada

Current hepatitis A status in Canada

Hepatitis A, caused by the hepatitis A virus, occurs most frequently in developing countries, but also causes sporadic cases or outbreaks in industrialized countries. The most common route of transmission is fecal-oral. The incidence of hepatitis A varies with geography, and economic and environmental conditions. The epidemiological pattern of the disease has changed with improvements in hygiene and economic conditions. The incidence and prevalence of hepatitis A has decreased, while the average age of exposure and subsequent infection has increased. The present report describes the current status of hepatitis A in Canada. The incidence rate of reported cases in Canada varies from over 10/100,000 (1991) to 3.6/100,000 (1998), and is higher in males, 4.7/100,000 (1998), than in females, 2.5/100,000 (1998). The highest reported hepatitis A rates are in age groups 30 to 39 years and 40 to 59 years, and in British Columbia. Such information is important for assessing current immunization approaches and for decision-making about new preventive strategies against hepatitis A in Canada

Comparison of DNA Amplification, mRNA Amplification, and DNA Hybridization Techniques for Detection of Cytomegalovirus in Bone Marrow Transplant Recipients

A total of 676 specimens from 63 recipients of bone marrow allografts were tested for cytomegalovirus (CMV) by the following assays: CMV pp67 NucliSens (NS), AMPLICOR CMV MONITOR (RA), and the Digene CMV DNA test (DG). In a consensus analysis, the sensitivities and specificities were 60 and 99% (NS), 96 and 98% (RA), and 90 and 76% (DG), respectively; for detection of symptomatic CMV infection, they were 60 and 97% (NS), 65 and 97% (RA), and 95 and 77% (DG), respectively. In multivariate analysis, the major risk factor for symptomatic CMV infection was an increase in the viral load in the DG assay; in univariate analyses, maximum viral loads in both DG and RA assays and a rising viral load in the RA assay were also significant. The earliest detection of CMV replication was provided by the RA assay (mean, 39 days posttransplantation), followed by the DG assay (mean, 48 days) and the NS assay (mean, 58 days)

“HERDOO2” clinical decision rule to guide duration of anticoagulation in women with unprovoked venous thromboembolism. Can I use any d-Dimer?

International audienc