Genotypic and phenotypic characteristics of Escherichia coli involved in transfusion-transmitted bacterial infections: implications for preventive strategies.

BACKGROUND: Transfusion-transmitted bacterial infections (TTBIs) are the main residual infectious complications of transfusions. Escherichia coli and platelet (PLT) concentrates may be epidemiologically associated, leading to severe, if not lethal, TTBIs. We investigated the genotypic and phenotypic reasons for this clinically deleterious combination. STUDY DESIGN AND METHODS: We investigated a French national E. coli strain collection related to six independent episodes of TTBIs. Their phenotypic characterizations included antibiotic susceptibility testing, growth testing under different culture conditions, serum survival assays, and virulence in a sepsis mouse model. Their genotypic characterizations included polymerase chain reaction phylotyping, whole genome sequencing, and a subsequent in silico analysis. RESULTS: We highlighted a selection process of highly extraintestinal virulent strains, mainly belonging to the B2 phylogroup, adapted to the hostile environment (high citrate concentration and a bactericidal serum effect) of apheresis-collected platelet concentrates (PCs). Compared to controls, the E. coli TTBI strains grew faster in the PCs due to a superior ability to capture iron. The in vitro growth performances were highly compatible with blood-derived product real-life conditions, including storage conditions and delays. The consistent serum resistance of TTBI strains promotes their survival in both the donor's and the receiver's blood and in the PCs. CONCLUSION: This study pointed out that E. coli strains responsible for TTBI exhibit very specific traits. They belong to the extraintestinal pathogenic phylogroups and have a high intrinsic virulence. They can be resistant to complement, capture iron, and grow in the apheresis-collected PCs. These findings therefore support the reinforcement of the postdonation information.

Residual risk and retrospective analysis of transfusion-transmitted bacterial infection reported by the French National Hemovigilance Network from 2000 to 2008.

BACKGROUND: Regarding blood safety, transfusion-transmitted bacterial infection (TTBI) remains the most frequent infectious risk. The incidence of these episodes needs to be assessed and updated frequently to accurately manage this risk. STUDY DESIGN AND METHODS: TTBIs were reported by the French network of local correspondents in each hospital and blood center. The regional coordinator managed the investigation. A multidisciplinary expert group from the French National Agency of Medicine and Health Products Safety (ANSM) analyzed each TTBI according to a standardized scale of imputability and severity. Only cases with likely or certain imputability are reported in this study. RESULTS: In France, 18.0 × 10(6) red blood cell (RBC) products, 1.94 × 10(6) platelet concentrates (PCs), and 2.44 × 10(6) fresh-frozen plasma units were transfused throughout 2000 to 2008. The incidence of TTBI was 2.45, 24.7, and 0.39 per million blood components (BCs), PCs, and RBCs, respectively. For PCs, the incidences of severe (vital threat or death) and fatal TTBI were 13.4 and 5.14 per million, respectively. PCs were responsible for 87% of TTBIs. A total of 66.7% of the implicated bacteria were Gram positive, most of them belonging to the normal skin flora. A total of 33.3% of the other implicated bacteria were Gram negative. CONCLUSION: The French hemovigilance system provides an accurate estimate of the TTBI incidence during a period with diversion and improving skin disinfection but without bacterial detection screening. This tool would be able to evaluate further additional safety procedures like bacterial screening and pathogen reduction technology.

Epidemiology of Transfusion Related Acute Lung Injury in France: Preliminary Results.

SUMMARY: The French Hemovigilance Network has been established in 1994 and records all adverse events associated with the transfusion of a labile blood products (LBP) regardless of their severity. From 1994 to 2006 35,423,172 LBP were issued, 85,812 adverse transfusion reactions notified, and 139 cases of transfusion related acute lung injury (TRALI) observed. The LBP most at risk is fresh frozen plasma (FFP), followed by platelets concentrates (PC) and packed red cells (PRC). However, because the use of FFP is not frequent in France, it only accounts for about 10% of TRALI, whereas PRC and PC are involved in the remaining cases. In no case, pooled FFP treated with solvent-detergent were involved. Patients' profiles are peculiar with a high disease burden. Therefore, targeting a prevention policy only on FFP would result in a marginal reduction of TRALI in France.

Fatal Yersinia enterocolitica biotype 4 serovar O:3 sepsis after red blood cell transfusion.

BACKGROUND: Although posttransfusion bacterial sepsis is rare, this complication is associated with a high mortality rate. CASE REPORT: A fatal case of septic shock was observed in a 71-year-old patient following transfusion of contaminated red blood cells (RBCs) for refractory anemia. Yersinia enterocolitica was isolated from the patient's blood sample and the transfused RBCs. Both strains were of bioserotype 4/O:3 and had the same NotI pulsotype. High titers of antibodies against Y. enterocolitica were detected in the donor's plasma sample 1 month after blood donation. The donor reported abdominal discomfort 3.5 months before blood collection but had no clinical signs of intestinal infection at the time of donation. CONCLUSION: Y. enterocolitica has been identified with increased frequency as a causative agent of posttransfusion septic shock. This nationwide investigation of these cases led to an estimated incidence of one case per 6.5 million RBC units distributed in France. Although rare, this often fatal complication remains nonpreventable worldwide owing to the lack of practical means for screening RBCs before transfusion.

Interest of transjugular liver biopsy in adult patients with haemophilia or other congenital bleeding disorders infected with hepatitis C virus.

Liver histology is important for prognosis and treatment strategy in patients with hepatitis C. We report a 10-year experience of transjugular liver biopsy (TJLB) in patients with haemophilia and other congenital bleeding disorders (CBD) in terms of safety, efficiency and therapeutic consequences. TJLB was proposed to patients who were regularly followed for CBD, and were hepatitis C virus (HCV) positive by polymerase chain reaction. Patients with inhibitors or who were human immunodeficiency virus (HIV) positive with CD4 cells <0.2 x 10(9)/l or with evidence of liver failure were excluded. TJLB was performed during a short hospitalization with factor replacement. Between 1992 and 2002, 88 TJLB were performed in 69 of 151 adult HCV patients (39% HIV positive). CBD was haemophilia A in 68% and haemophilia B in 24%. Few mild adverse events were recorded. Histology was assessable in 78 of 88 procedures (89%). Twenty-nine (37%) cases demonstrated minimal change (METAVIR A