The relationship between the duration of platelet storage and the development of transfusion reactions

BACKGROUND: The incidence of platelet transfusion reactions may depend partly on the length of storage. The influence of reactions on the effectiveness of platelet transfusions is not known. STUDY DESIGN AND METHODS: Platelet transfusion reactions, identified by prospective monitoring, were analyzed for the effects of component type, recipient lymphocytotoxic antibodies, bacterial contamination, and duration of storage. Posttransfusion corrected count increments (CCIs) were used to evaluate the effectiveness of transfusions associated with reactions by comparing them to those of randomly selected transfusions without reactions. RESULTS: Reactions accompanied 4 percent of the 4926 transfusions given and included 119 febrile nonhemolytic transfusion reactions, 62 allergic reactions, and 13 reactions with features of both. Platelet concentrates contained a mean of 0.5 × 10(8) white cells per unit. Lymphocytotoxic antibodies were detectable in 20 of 84 recipients tested proximate to a reaction. Bacterial cultures from 4 of 81 units were positive; 1 unit was associated with fatal Enterobacter sp. sepsis. The incidence of febrile nonhemolytic transfusion reactions but not allergic reactions was related to platelet storage duration. The CCI was not significantly different for transfusions associated with reactions (10.97 [median, range 0–72.5; n = 165]) or not so associated (13.1 [median, range 0–39.5; n = 174]) (p = 0.08). CONCLUSION: The incidence of febrile nonhemolytic transfusion reactions but not allergic reactions appears to be related to the duration of platelet storage. Transfusion reactions may not have an adverse impact on the effectiveness of platelet transfusions.     

Validation of a simple method to count very low white cell concentrations in filtered red cells or platelets

The increased performance of white cell (WBC) filters makes it difficult to count precisely the number of residual WBCs. Concentrations as low as 0.01 WBC per microL cannot be determined with electronic cell counters, conventional hemocytometers, or the flow cytometric techniques currently being used. This article describes a simple, manual method using a Nageotte hemocytometer with a large-volume chamber (50 microL) to count the number of WBCs contained in red cell (RBC) suspensions (preparations A, B, and C) and in platelet suspensions (preparation D) diluted 1 in 10 pure, or concentrated two fold. To validate the method, several reference ranges, prepared by successively adding mononuclear cells to a suspension of pure RBCs or platelets, were used. Among the different series, validation ranges varied from 0.2 to 12 to 0.01 to 0.5 WBCs per microL and correlation coefficients ranged from 0.929 to 0.996. To determine the limit of accurate detection, accuracy tests (n = 160) were carried out by two experienced operators on samples with WBC concentrations of about 5, 10, and 120 times the concentration at the theoretical limit of detection (1 WBC/chamber). No significant difference was observed in the various types of preparations (A, B, C, D) in the tests performed by the two operators. However, intra-assay coefficients of variation were 18, 9.5, and 2.2 percent, respectively, at WBC concentrations of 5, 10, and 120 times that at the theoretical limit of detection. These observations show that a limit of accurate detection (10%) seems to be reached when 10 cells are observed in a Nageotte hemocytometer.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hepatitis A virus infections associated with clotting factor concentrate in the United States

BACKGROUND: Two cases of hepatitis A among persons exposed to the same lot of solvent/detergent-treated antihemophilic factor VIII concentrate were reported to a surveillance system. An investigation was conducted to find additional cases and determine the source of infection. STUDY DESIGN AND METHODS: A seroprevalence study was conducted among persons with exposure to the suspect lot for serologic evidence of recent infection with hepatitis A virus (HAV). RESULTS: Six cases of recent HAV infection were discovered: four of the patients had been infused with material from the suspect lot of factor VIII, and two had received infusions of factor IX concentrate made from plasma pools common to the suspect factor VIII lot. HAV was identified in one of the plasma pools, in the factor VIII product, and in serum or stool from two factor VIII recipients and one factor IX recipient. The genetics sequence of the virus in the plasma pool, the factor VIII lot, and the factor VIII recipients were identical, while that of the virus in the factor IX recipient differed by a single base. CONCLUSION: These data document the transmission of HAV by a factor VIII concentrate and implicate factor IX products manufactured from a common source-plasma pool.     

Development of a theory- and evidence-based intervention to enhance implementation of physical therapy guidelines for the management of low back pain

Background

Systematic planning could improve the generally moderate effectiveness of interventions to enhance adherence to clinical practice guidelines. The aim of our study was to demonstrate how the process of Intervention Mapping was used to develop an intervention to address the lack of adherence to the national CPG for low back pain by Dutch physical therapists.

Methods

We systematically developed a program to improve adherence to the Dutch physical therapy guidelines for low back pain. Based on multi-method formative research, we formulated program and change objectives. Selected theory-based methods of change and practical applications were combined into an intervention program. Implementation and evaluation plans were developed.

Results

Formative research revealed influential determinants for physical therapists and practice quality managers. Self-regulation was appropriate because both the physical therapists and the practice managers needed to monitor current practice and make and implement plans for change. The program stimulated interaction between practice levels by emphasizing collective goal setting. It combined practical applications, such as knowledge transfer and discussion-and-feedback, based on theory-based methods, such as consciousness raising and active learning. The implementation plan incorporated the wider environment. The evaluation plan included an effect and process evaluation.

Conclusions

Intervention Mapping is a useful framework for formative data in program planning in the field of clinical guideline implementation. However, a decision aid to select determinants of guideline adherence identified in the formative research to analyse the problem may increase the efficiency of the application of the Intervention Mapping process.     

Empfehlungen der Projektgruppe Prävention der DGK zur risikoadjustierten Prävention von Herz- und Kreislauferkrankungen

Platelet inhibitors

In patients with vascular diseases platelet inhibitors are usually administered as long-term medication. In patients without vascular diseases they are indicated for preventive reasons only in patients with high cardiovascular risk (≥5% SCORE or ≥20% PROCAM) taking risks and side effects into account. In patients with type 2 diabetes without vascular disease platelet inhibitors are not indicated.

Hormone replacement therapy

Cardiovascular diseases are the most important causes of death in menopausal women. Although observational studies and mechanistic studies have suggested a preventive effect hormone replacement therapy does not prevent cardiovascular events and is not indicated. There is an increased risk of thromboembolism with hormone replacement therapy. If it is used for symptomatic reasons the best possible control of all cardiovascular risk factors should be attempted.

Lifestyle modification and psychosocial risk factors

Long-term adherence to complex medication regimens and to a healthy lifestyle frequently suffers from low acceptance. Persons with low socioeconomic status and/or low education are particularly at risk. Non-guideline adherent medication and an unfavourable lifestyle are associated with a higher cardiac event rate. Social isolation, chronic familial or vocational stress, fear of side effects of medications, low motivation and (frequently unrecognized) nicotine dependence contribute to decreased adherence. Increased attention to these factors and in particular an individually adapted communication procedure taking these patient factors into account can mitigate these problems. A 10-item program is proposed to improve communication and adherence to treatment.     

Polymorphous low-grade adenocarcinoma: a case report

We present a case of de novo polymorphous low-grade adenocarcinoma (PLGA) arising in a minor salivary gland with a relatively large radiographic extent compared with that of most of the PLGAs reported. This paper describes the radiographic extent of the lesion and the findings of CT imaging.     

Identifying environmental health priorities in underserved populations: a study of rural versus urban communities

Objectives

Understanding and effectively addressing persistent health disparities in minority communities requires a clear picture of members' concerns and priorities. This study was intended to engage residents in urban and rural communities in order to identify environmental health priorities. Specific emphasis was placed on how the communities: defined the term environment; their perceptions of environmental exposures as affecting their health; specific priorities in their communities; and differences in urban versus rural populations.

Study design

A community-engaged approach was used to develop and implement focus groups and compare environmental health priorities in urban versus rural communities.

Methods

A total of eight focus groups were conducted: four in rural and four in urban communities. Topics included: defining the term environment; how the environment may affect health; and environmental priorities within their communities, using both open discussion and a predefined list. Data were analysed both qualitatively and quantitatively to identify patterns and trends.

Results

There were important areas of overlap in priorities between urban and rural communities; both emphasized the importance of the social environment and shared a concern over air pollution from industrial sources. In contrast, for urban focus groups, abandoned houses and their social and physical sequelae were a high priority while concerns about adequate sewer and water services and road maintenance were high priorities in rural communities.

Conclusions

This study was able to identify environmental health priorities in urban versus rural minority communities. In contrast to some previous risk perception research, the results of this study suggest prioritization of tangible, known risks in everyday life instead of rare, disaster-related events, even in communities that have recently experienced devastating damage from tornadoes. The findings can help inform future efforts to study, understand and effectively address environmental issues, and are particularly relevant to developing effective community-based strategies in vulnerable populations.     

Topical class I corticosteroids in 10 patients with bullous pemphigoid: correlation of the outcome with the severity degree of the disease and review of the literature

BACKGROUND: Treatment of bullous pemphigoid (BP) with systemic immunosuppressive agents, in particular with systemic corticosteroids, has many long-term side-effects. A dozen reports were published regarding the efficacy of topical corticosteroids in the treatment of bullous pemphigoid. OBJECTIVE: To evaluate the efficacy of potent class I topical corticosteroids in relation to the affected body surface area (BSA) in patients with bullous pemphigoid and to review the literature. METHODS: An open prospective trial with 10 patients with BP with measurement of the affected BSA. Treatment protocol consisted of three steps: potent class I topical corticosteroid treatment, systemic tetracyclines and systemic corticosteroids. Follow-up period was between 24 and 72 months. RESULTS: Our study suggests a correlation between the success rate of topical corticosteroid treatment and the body surface area initially affected: all patients with an affected BSA of less than 20% healed with topical treatment only. The patients with more than 40% affected BSA needed systemic treatment with steroids. CONCLUSION: Topical class I corticosteroids seem to be effective in healing lesions of BP, especially if less than 20% of the BSA is affected. This study comprises only 10 patients, making further studies necessary to draw definite conclusions.