Zaza S, Tokars J I, Yomtovian R, Hirschler N V, Jacobs M R, Lazarus H M, Goodnough L T, Bland L A, Arduino M J, Jarvis W R
Hospital Infections Program, Centers for Disease Control and Prevention, Atlanta, GA 30333.
Infect Control Hosp Epidemiol. 1994 Feb;15(2):82-7. doi: 10.1086/646866.
A cluster of bacterial contamination of platelets occurred at a university hospital in a one-month period. This unusual clustering allowed us to examine the likely mechanism of contamination and clinical sequelae.
We reviewed medical records of patients receiving random donor platelet transfusions to determine numbers of platelets transfused, reactions reported, and episodes of bacterial contamination. We also reviewed procedures at the collecting blood agencies and the hospital blood bank.
Four patients received bacterially contaminated platelets during June and July 1991. The rates of reported platelet transfusion reactions increased significantly (P < 0.001) from September 1989 through July 1991 (study period); in addition, the rate of contamination of platelets during June and July 1991 was 23-fold higher than during the previous 21 months (P < 0.001). Surveillance methodology changed dramatically during the study period, contributing to the recognition of the current cluster. Pathogens isolated from the contaminated platelet pools were Bacillus cereus, Staphylococcus epidermidis, or Pseudomonas aeruginosa in titers ranging from 10(6) to 10(8) colony forming units/mL. Four constituent individual platelet units identified as the probable cause of the outbreak (including one postepidemic episode) were significantly older (mean age, 4.8 days) than 106 randomly selected individual platelet units (mean age, 3.7 days; P = 0.04). Platelet pools were transfused an average of 2.5 hours after pooling. Review of blood collection and platelet preparation practices did not identify breaks in procedure or technique that could have caused contamination.
Increased awareness of platelet transfusion reactions by clinical staff and routine culturing of all platelets associated with transfusion reactions will identify contaminated platelets. Identification of contaminated platelets is necessary to treat affected patients appropriately and to determine the prevalence of and risk factors for contaminated platelets (Infect Control Hosp Epidemiol 1994;15:82-87).
某大学医院在一个月内发生了一系列血小板细菌污染事件。这种不寻常的聚集现象使我们能够研究污染的可能机制及临床后果。
我们查阅了接受随机供者血小板输注患者的病历，以确定输注的血小板数量、报告的反应以及细菌污染事件。我们还审查了采血机构和医院血库的操作程序。
1991年6月和7月，有4名患者接受了被细菌污染的血小板。从1989年9月至1991年7月（研究期），报告的血小板输血反应发生率显著增加（P < 0.001）；此外，1991年6月和7月血小板污染率比前21个月高23倍（P < 0.001）。在研究期间，监测方法发生了巨大变化，这有助于识别当前的聚集事件。从受污染的血小板库中分离出的病原体为蜡样芽孢杆菌、表皮葡萄球菌或铜绿假单胞菌，滴度范围为10(6)至10(8)菌落形成单位/毫升。确定为此次暴发可能原因的4个组成单个血小板单位（包括1例流行后事件）明显比106个随机选择的单个血小板单位年龄大（平均年龄4.8天）（平均年龄3.7天；P = 0.04）。血小板库在汇集后平均2.5小时输注。对采血和血小板制备操作的审查未发现可能导致污染的程序或技术失误。
临床工作人员对血小板输血反应的认识提高以及对所有与输血反应相关的血小板进行常规培养，将有助于识别受污染的血小板。识别受污染的血小板对于妥善治疗受影响的患者以及确定受污染血小板的患病率和危险因素是必要的（《感染控制与医院流行病学》1994年；15:82 - 87）。
