Bacterial contamination of platelets at a university hospital: increased identification due to intensified surveillance
Related Experiment Videos
S Zaza1, J I Tokars, R Yomtovian
1Hospital Infections Program, Centers for Disease Control and Prevention, Atlanta, GA 30333.
Background:
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.
Methods:
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.
Results:
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.
Conclusions:
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).
Insights
Bacterial contamination of platelets led to increased transfusion reactions. Routine culturing and staff awareness are crucial for identifying contaminated platelets and preventing adverse events.
Area of Science:
- Hematology
- Infectious Diseases
- Public Health
Background:
- A university hospital experienced a cluster of bacterial contamination in platelet transfusions over one month.
- This event prompted an investigation into the contamination mechanisms and clinical outcomes.
Observation:
- Four patients received bacterially contaminated platelets between June and July 1991.
- Platelet transfusion reactions and contamination rates significantly increased during the study period.
- Pathogens identified included Bacillus cereus, Staphylococcus epidermidis, and Pseudomonas aeruginosa.
Findings:
- Older individual platelet units (mean age 4.8 days) were implicated as the source of contamination.
- Contaminated platelet pools were transfused shortly after pooling (average 2.5 hours).
- No procedural breaks in blood collection or preparation were identified as the cause.
Implications:
- Enhanced surveillance and routine culturing of platelets are necessary to detect contamination.
- Early identification of contaminated platelets is vital for patient treatment and risk factor analysis.
- Increased clinical staff awareness of transfusion reactions aids in recognizing contaminated products.