Hemovigilance monitoring of platelet septic reactions with effective bacterial protection systems

Abstract

BACKGROUND Delayed, large‐volume bacterial culture and amotosalen/ultraviolet‐A light pathogen reduction are effective at reducing the risk of bacterial proliferation in platelet concentrates (PCs). Hemovigilance programs continue to receive reports of suspected septic transfusion reactions, most with low imputability. Here, we compile national hemovigilance data to determine the relative efficacy of these interventions. STUDY DESIGN AND METHODS Annual reports from the United Kingdom, France, Switzerland, and Belgium were reviewed between 2005 and 2016 to assess the risk of bacterial contamination and septic reactions. RESULTS Approximately 1.65 million delayed, large‐volume bacterial culture‐screened PCs in the United Kingdom and 2.3 million amotosalen/ultraviolet‐A–treated PCs worldwide were issued with no reported septic fatalities. One definite, one possible, and 12 undetermined/indeterminate septic reactions and eight contaminated “near misses” were reported with delayed, large‐volume bacterial cultures between 2011 and 2016, for a lower false‐negative culture rate than that in the previous 5 years (5.4 vs. 16.3 per million: odds ratio, 3.0; 95% confidence interval, 1.4‐6.5). Together, the Belgian, Swiss, and French hemovigilance programs documented zero probable or definite/certain septic reactions with 609,290 amotosalen/ultraviolet‐A–treated PCs (<1.6 per million). The rates were significantly lower than those reported with concurrently transfused, nonpathogen‐reduced PCs in Belgium (<4.4 vs. 35.6 per million: odds ratio, 8.1; 95% confidence interval,1.1‐353.3) and with historic septic reaction rates in Switzerland (<6.0 vs. 82.9 per million: odds ratio, 13.9; 95% confidence interval, 2.1‐589.2), and the rates tended to be lower than those from concurrently transfused, nonpathogen‐reduced PCs in France (<4.7 vs. 19.0 per million: odds ratio, 4.1; 95% confidence interval, 0.7‐164.3). CONCLUSION Pathogen reduction and bacterial culture both reduced the incidence of septic reactions, although under‐reporting and strict imputability criteria resulted in an underestimation of risk.

Bacterial inactivation of platelet concentrates with the THERAFLEX UV‐Platelets pathogen inactivation system

“…During storage, such undetected bacteria in PCs may grow to levels that can induce acute sepsis and even fatal reactions in recipients . PI technologies promise to significantly and proactively reduce the risk of bacterial sepsis associated with platelet products . PI treatment, however, must cope with a wide range of bacterial species, concentrations, and resistance mechanisms.…”

Concerning the efficacy of pathogen inactivation

“…The maximum time between collection and treatment is thus limited by the efficacy of the pathogen inactivation treatment process. This has been demonstrated in the laboratory and in actual use …”

“…Neither did he mention the use of pathogen inactivation in preventing bacterial sepsis. The latter has been shown, by hemovigilance reporting, to be efficacious in actual practice …”

Microbiological Screening of Platelet Concentrates in Europe

“…In Belgium, France, and Switzerland, where PR treatment for PC was introduced in recent years, no septic reactions were reported since its implementation. Compared to historical data, the rates of microbiologically contaminated PC decreased significantly from 19, 82.9, and 35.6 per million cases to zero cases in France, Switzerland, and Belgium, respectively [9]. …”

“…Frequently employed additives in the storage solution might serve as an additional energy source for some microorganisms resulting in a growth advantage [8]. The clinical relevance of bacterial PC contamination is confirmed by hemovigilance reports of transfusion incidents [9]. According to current knowledge, clinical complications caused by bacterial transmission range from mild septic reactions accompanied by fever up to severe septic shock and death of the recipients [10-12].…”