Determination of the degree of bacterial contamination of whole-blood collections using an automated microbe-detection system

BACKGROUND: The prevalence of bacterial contamination in whole-blood collections, either with immediate sampling or sampling after overnight storage as whole blood at 20 degrees C, is determined. STUDY DESIGN AND METHODS: Whole blood was collected under blood bank conditions in special five-bag systems, allowing sampling in a closed system for culture bottles. Samples were taken within 2 hours after collection (Group 1) or after overnight storage of the whole blood at 20 degrees C (Group 2). Culture bottles were incubated for 7 days, and positive samples were entered on agar plates for confirmation and determination. RESULTS: In Group 1, 9219 units were tested; 27 units were positive with positive subculture, that is, 0.29 percent with a 95% CI of 0.19 to 0.42 percent. In Group 2, 9038 units were tested; 36 units were positive with positive subculture, that is, 0.39 percent with a 95% CI of 0.28 to 0.55 percent. No significant difference could be found between the two test groups. The majority of bacteria were either Staphylococcus (all coagulase-negative) or Propionibacterium species. CONCLUSION: For a total of 18,257 units, 0.34 percent (CI, 0.25-0.44) of whole-blood collections appeared to have bacterial contamination (mainly skin-derived). Overnight storage of whole blood at 20 degrees C did not have a significant effect on the prevalence of bacterial contamination.     

Transfusion transmitted leishmaniasis: a case report and review of literature

Leishmaniasis is caused by the infection of haemoparasite Leishmania . The disease is a major public health problem in at least 88 countries, including India. Various species of Leishmania are involved in causing this disease. In India, Leishmania donovani species causes visceral leishmaniasis or kala-azar. The parasite is mainly transmitted from infected to uninfected person through the bites of female sandfly. Rarely the parasite can transmit through placenta from mother to child, through sexual intercourse, as laboratory acquired and through blood transfusion. This paper reports a unique case of transfusion-transmitted fatal kala-azar in an Indian infant who acquired this infection within few days of his birth after receiving blood from his maternal uncle, who was asymptomatic at the time of blood donation but died due to severe kala-azar within three months. The baby started having fever and developed hepatosplenomegaly within one month of blood transfusion and in spite of repeated anti-leishmanial treatment with sodium antimony gluconate the child died at the age of 7 months. This paper details the clinico-pathological findings of this child and also reviews the literature on this aspect and its impact on transfusion medicine.     

Transfusion transmitted Yersinia enterocolitica infection in New Zealand

Abstract Aims: To update and summarise cases of transfusion-transmitted Yersinia enterocolitica infection in New Zealand and to evaluate critically suggested methods to reduce this rare but frequently fatal complication of blood transfusion.
Methods: Case reports of four recent transfusion-transmitted Y enterocolitica infections in New Zealand are given and previous reports reviewed. Literature review and evaluation of proposed methods to decrease the incidence of transfusing yersinia contaminated blood.
Results: There have been eight cases of transfusion-transmitted Y enterocolitica infection in New Zealand in the past five years. Four of the five deaths have been directly caused by the transfusion. This gives a transfusion incidence rate of one:65,000 and a fatality rate of one: 104,000 units transfused. This fatality rate is more than 80 times higher than that reported in the United States.
Conclusions: Why the incidence of transfusion-transmitted yersinia is so high is not clear, since we do not store blood as long as many other countries, particularly the United States. In Auckland, however, the cases came at a time when the number of yersinia isolates from the community is reported to be rising.
Many suggestions for the prevention of this problem have been put forward reflecting the fact that there is as yet no perfect solution. Those which are easy to implement and cheap to perform are largely already in place and investigation is continuing into the other alternatives.     

某市在校学生无偿献血者传染病筛查结果分析

目的 调查某市参加无偿献血的在校学生输血传染病指标的筛查结果,为完善招募策略、确保安全供血提供依据.方法 检测无偿献血学生和普通献血人群HBsAg、抗-HCV、抗-HIV、抗-TP,对4项感染指标的检出结果进行分析比较.结果 在校学生输血传染病指标检测总阳性率低于普通献血人群.学生无偿献血者中出现了HIV感染个例.结论 在校学生是无偿献血的主要群体、低危群体,向学生积极宣传无偿献血知识的同时,加强艾滋病防治教育势在必行.     

非甲至非戊型肝炎患者TTV检测和部分基因序列分析

目的：研究新近报道的一种与输血后肝炎有关的病毒在中国郑州地区正常人群、HBsAg阳性者、非甲至非戊型肝炎患者中的感染和基因序列变异情况。方法：采用TTV基因组ORF1区的套式聚合酶链反应(nested-PCR)方法对血清标本进行检测,并对非甲至非戊型肝炎患者中的TTV分离株进行序列测定。结果：TTV DNA在非甲至非戊型肝炎患者中检出率为45％(18／40);在正常体检者中检出率为17．7％(17／96);在HBsAg阳性者(ALT≤34 IU／L)中检出率22．7％(10／44)。TTV分离株序列与日本株(CLON22)相对应位置的核苷酸同源性为．1％。结论：TTV在非甲至非戊型肝炎患者TTV的感染率明显高于其他人群,可能是非甲至非戊型肝炎的主要致病因子。     

The status of blood safety in ECO member states

Background

Access to the information concerning blood safety is essential for managing problems and overcoming the challenges that are faced in any given region. Information on the availability and safety of blood in countries of the Economic Cooperation Organisation (ECO) is largely lacking. To address this problem, the Iranian Blood Transfusion Organisation, in collaboration with other ECO member states, initiated a research project in 2009 to collect, analyse and compare statistics on blood safety in the region.

Materials and methods

A modified and summarised version of the Global Database on Blood Safety (GDBS) questionnaire was used to collect data. The questionnaire was sent to all ten countries in the ECO region. The heads of the national transfusion services or focal points were requested to complete the form. Related literature and websites were also reviewed.

Results

Only three countries (Afghanistan, Iran and Turkey) completed the questionnaire, while other countries provided their available data on some parts of the questionnaire. The number of donations per year varied from 5 to 27/1,000 population. The rate of donors positive for human immunodeficiency virus ranged from 0.003% to 0.2%. The rate of donors positive for hepatitis C virus antibody varied from 0.05% to 3.9% while that of hepatitis B virus surface antigen ranged from 0.15% to 3.91% respectively.

Discussion

There is very clear diversity in blood transfusion services among ECO member states. Most countries in the region do not have a data-recording system. It is generally estimated that the need for blood is much higher than the supply in this region. Deficiencies in donor screening and a high prevalence of transfusion-transmitted infections are other important challenges.