Compliance to oseltamivir and subsequent occurrence of self-reported adverse drug reactions among nursery and primary school children following exposure to Influenza A(H1N1)v

During the containment phase of Influenza A(H1N1)v, a nursery, a primary school and an afterschool club were closed after two pupils were found confirmed cases. Classmates were prescribed postexposure oseltamivir. Compliance was expected to be low. The objective of this study was to assess compliance, the number of children developing adverse drug reactions (ADRs) and the reasons for stopping the course prematurely. We conducted a survey among parents of all classmates of the two cases. Parents were asked about compliance and adverse drug events in a questionnaire or underwent a telephone interview. Response was high, 88%. Seventy-nine percent of the children were compliant to the prescribed dose of oseltamivir. One in four children experienced at least one ADR. Children who took a higher daily dose (treatment dose) developed significantly more often ADRs. No children developed Influenza A(H1N1)v. We found that a high overall compliance to prescribed oseltamivir can be achieved in very young children (1-11 years). The proportion of children developing ADRs was much lower than described in two other recent UK investigations. Possibly, this is related to the socioeconomic status of the population under investigation.

A dominant role for the immunoproteasome in CD8+ T cell responses to murine cytomegalovirus

Murine cytomegalovirus (MCMV) is an important animal model of human cytomegalovirus (HCMV), a β-Herpesvirus that infects the majority of the world's population and causes disease in neonates and immunocompromised adults. CD8⁺ T cells are a major part of the immune response to MCMV and HCMV. Processing of peptides for presentation to CD8⁺ T cells may be critically dependent on the immunoproteasome, expression of which is affected by MCMV. However, the overall importance of the immunoproteasome in the generation of immunodominant peptides from MCMV is not known. We therefore examined the role of the immunoproteasome in stimulation of CD8⁺ T cell responses to MCMV – both conventional memory responses and those undergoing long-term expansion or “inflation”. We infected LMP7^−/− and C57BL/6 mice with MCMV or with newly-generated recombinant vaccinia viruses (rVVs) encoding the immunodominant MCMV protein M45 in either full-length or epitope-only minigene form. We analysed CD8⁺ T cell responses using intracellular cytokine stain (ICS) and MHC Class I tetramer staining for a panel of MCMV-derived epitopes. We showed a critical role for immunoproteasome in MCMV affecting all epitopes studied. Interestingly we found that memory “inflating” epitopes demonstrate reduced immunoproteasome dependence compared to non-inflating epitopes. M45-specific responses induced by rVVs remain immunoproteasome-dependent. These results help to define a critical restriction point for CD8⁺ T cell epitopes in natural cytomegalovirus (CMV) infection and potentially in vaccine strategies against this and other viruses.

Zebrafish mutants with disrupted early T-cell and thymus development identified in early pressure screen

Generation of mature T lymphocytes requires an intact hematopoietic stem cell compartment and functional thymic epithelium. We used the zebrafish (Danio rerio) to isolate mutations that affect the earliest steps in T lymphopoiesis and thymic organogenesis. Here we describe the results of a genetic screen in which gynogenetic diploid offspring from heterozygous females were analyzed by whole-mount in situ hybridization for the expression of rag-1. To assess immediately if a global defect in hematopoiesis resulted in the mutant phenotype, alpha-embryonic globin expression was simultaneously assayed for multilineage defects. In this report, we present the results obtained with this strategy and show representative mutant phenotypes affecting early steps in T-cell development and/or thymic epithelial cell development. We discuss the advantage of this strategy and the general usefulness of the zebrafish as a model system for vertebrate lymphopoiesis and thymic organogenesis.

Pulmonary hypertension in children and adolescents with sickle cell disease

The prevalence of pulmonary hypertension (PHTN) in the pediatric sickle cell disease (SCD) population is not known despite its high prevalence in adult patients. Our hypothesis was that increased pulmonary artery pressures (PAPs) would be found in SCD children and adolescents, especially those with a history of pulmonary complications: acute chest syndrome, obstructive sleep apnea, asthma, and reactive airway disease. Fifty-two SCD children, 23 of whom had underlying pulmonary disease, were screened for PHTN, which was defined as a tricuspid regurgitant jet velocity (TRV) of at least 2.5 m/s. Twenty-four (46.15%) SCD patients had increased PAP (i.e., TRV > or =2.5 m/s), and 6 (11.5%) had significant PHTN (i.e., TRV > or =3.0 m/s). Pulmonary disease was marginally associated with PHTN (odds ratio 2.80 and confidence interval 0.88 to 8.86; p = 0.0795). As in adult SCD patients with PHTN, this complication was correlated with the degree of hemolysis as manifested by significantly higher lactate dehydrogenase and bilirubin, lower hemoglobin and hematocrit levels, and a strong association with Hb-SS phenotype. However, after statistical adjustment for age and sex, increased serum LDH was not associated with the development of PHTN. Further studies are needed to clarify the prevalence and mechanisms of PHTN in pediatric and adolescent patients with SCD.

Diversity of needle exchange provision in the UK: findings from a national survey

Needle exchanges are key to reducing transmission of bloodborne viruses (BBVs) in injecting drug users (IDUs) through the provision of sterile