Current incidence and residual risk of HIV, HBV and HCV at Canadian Blood Services

The impact of pre-donation viral markers screening of new blood donors on blood safety

BACKGROUND

The risk of transfusion-transmissible infections (TTIs) remains a concern in transfusion medicine. Since the rate of infection among first-time blood donors is higher than repeated donors, strategies to enhance blood safety can focus on new donors. The aim of the study was to investigate the effect of pre-donation viral screening of new donors on blood safety.

METHODS AND MATERIALS

The pre-donation screening of new donors was implemented in the Kurdistan blood center. In this program, new donors who met the blood donation criteria were informed about the program and only a blood sample was donated for HBs Ag, HCV Ab, and HIV Ab testing. New donors with negative results were invited to donate blood after 12 weeks. A unit of blood was collected from eligible returned donors. Laboratory tests were performed again using the same methods. Finally, the prevalence of confirmed positive TTI results among donated blood in Kurdistan blood center was compared before and after the establishment of program.

RESULTS

During the study, 4,434 new donors were screened for viral markers. A total of 41 new donors (0.92%, 95% CI, 0.007-0.13) had repeatedly reactive results and infection was confirmed in blood sample of 24 donors (0.54%, 95% CI, 0.003-0.008). Overall, 56% of new donors returned for blood donation. Prevalence of confirmed TTIs markers in collected blood units was 0.27% and 0 before and after implementing program, respectively.

CONCLUSIONS

This study indicated that Pre-donation screening can reduce the risk of TTI transmission by identifying infected donors at the pre-donation phase.

HIV, HTLV, and Hepatitis B and C Infection in Blood Donors in Bahia, Brazil from 2008 to 2017

Although blood transfusion is an important therapeutic resource, transfusion-transmitted infections (TTIs) are still a cause for concern. Measures to mitigate this risk involve improvement of donor screening criteria and improvements in laboratory tests, especially the use of nucleic acid test (NAT). In this retrospective study we evaluated HIV, HTLV, HCV and HBV infection rates in blood donors of the Hematology and Hemotherapy Foundation of Bahia (Hemoba), Brazil, through serological and NAT results and the characteristics of donors. From February/2008 to December/2017, 777,446 blood donations were made. Most donors were male, aged 25-44 years, black and mixed race, and single or divorced. The density-type incidence (DTI; per 100,000) for each virus was 91.1 for HBV; 66.5 for HCV; 54.3 for HIV; and 33.9 for HTLV, with a decreasing trend observed over the period studied, except in the last biennium. NAT detected only 1 donor in immunological window for HIV (0.46/100,000 donations) and 3 donors in immunological window for HBV (1.8/100,000 donations). Serological positivity for all viruses studied was higher in the metropolitan region of Salvador, the state capital. Conclusion: DTI rates show a decreasing trend over the years studied, with a predominance of HBV infection. NAT allowed the detection of donors in immunological window periods, having an important role in improving transfusion safety.

A novel autotransfusion device saving erythrocytes and platelets used in a 72 h survival swine model of surgically induced controlled blood loss

BACKGROUND

The purpose of this study was to develop a swine model of surgically induced blood loss to evaluate the performances of a new autotransfusion system allowing red blood cells and platelets preservation while collecting, washing and concentrating hemorrhagic blood intraoperatively.

METHODS

Two types of surgically induced blood loss were used in 12 minipigs to assess system performance and potential animal complications following autotransfusion: a cardiac model (cardiopulmonary bypass) and a visceral model (induced splenic bleeding). Animal clinical and hematological parameters were evaluated at different time-points from before bleeding to the end of a 72-hour post-transfusion period and followed by a post-mortem examination. System performances were evaluated by qualitative and quantitative parameters.

RESULTS

All animals that received the autotransfusion survived. Minimal variations were seen on the red blood cell count, hemoglobin, hematocrit at the different sampling times. Coagulation tests failed to show any hypo or hypercoagulable state. Gross and histologic examination didn't reveal any thrombotic lesions. Performance parameters exceeded set objectives in both models: heparin clearance (≥ 90%), final heparin concentration (≤ 0.5 IU/mL), free hemoglobin washout (≥ 90%) and hematocrit (between 45% and 65%). The device treatment rate of diluted blood was over 80 mL/min.

CONCLUSIONS

In the present study, both animal models succeeded in reproducing clinical conditions of perioperative cardiac and non-cardiac blood loss. Sufficient blood was collected to allow evaluation of autotransfusion effects on animals and to demonstrate the system performance by evaluating its capacity to collect, wash and concentrate red blood cells and platelets. Reinfusion of the treated blood, containing not only concentrated red blood cells but also platelets, did not lead to any postoperative adverse nor thrombogenic events. Clinical and comparative studies need to be conducted to confirm the clinical benefit of platelet reinfusion.

Subjective donor deferral as a tool for increased blood transfusion safety: A cross-sectional observational study

OBJECTIVES

This study aims at evaluating whether subjective donor deferral (SDD) has the potential for increasing blood transfusion safety.

BACKGROUND

Appropriate donor selection via clinical and serologic screening is necessary to prevent transfusion-transmissible infections (TTIs). One additional strategy adopted by some Brazilian blood transfusion centers (BTCs) is the rejection of a donation by the pre-donation interviewer based on subjective factors.

METHODS/MATERIALS

We conducted a STROBE-guided cross-sectional study including 105 005 prospective donors who presented to our BTC between 1 January 2013, and 31 December 2015. Donors were evaluated for age, gender, education level, donation type and history, confidential unit exclusion, SDD, and results of serologic screening for TTIs.

RESULTS

Even after controlling for potential confounding variables, subjectively deferred donors were more likely to have at least one reactive serology in the standard screening (OR: 2.80; 95% CI: 2.13-3.69; P < .001). They also had a higher risk for testing positive for syphilis (OR: 4.47; 95% CI: 3.05-6.55; P < .001), hepatitis B (OR: 5.69; 95% CI: 2.48-13.08; P < .001), and HIV (OR: 6.14; 95% CI: 3.22-11.69; P < .001).

CONCLUSIONS

Routine implementation of SDD in donor selection may be an effective additional measure to avoid TTIs, highlighting the importance of interviewer experience, perspicacity, and face-to-face contact with donors for blood safety assurance.

Prevalence of sickle cell trait and its association to renal dysfunction among blood donors at University of Medical Sciences Teaching Hospital, Ondo, Nigeria

Introduction

Prospective blood donors are routinely screened for blood borne infections but medical illnesses and haemoglobin genotype are overlooked despite a high prevalence of haemoglobin AS among Nigerian donors.

Objective

To determine the prevalence of haemoglobin AS and its association to renal function, if any.

Method

Apparently healthy donors were studied between February and December 2018. Their haemoglobin genotype and, estimated glomerular filtration rates were determined.

Results

There were 96 males (94.1%) and 6 (5.9%) females with mean age of 26.7±4.5 years (range 19–44 years) and mean eGFR of 103.97±19.00ml/min/1.73m2. Eighty one (79.4%) and 21 (20.6%) subjects had haemoglobin AA and AS genotypes respectively. The mean eGFR for subjects with haemoglobin AA and AS were 105.2±18.6ml/min/1.73m² and 99.9 ± 21.2ml/min/1.73m² respectively (p value = 0.270). Eighty one (79.4%), 20 (19.6%) and 1 (1.0%) subjects had renal function at >90ml/min/1.73m², 60–89ml/min/1.73m² and 30–59ml/min/m² respectively. There was no significant difference in the mean eGFR between subjects with haemoglobin AA and AS (mean difference 5.3, p = 0.265, 95%CI = -4.07 to 14.60).

Conclusion

The prevalence of sickle cell trait among Nigerian blood donors is high. There is no significant difference in the renal function status of blood donors with SCT and normal haemoglobin genotype.

Array testing for multiplex assays

Group testing involves pooling individual specimens (e.g., blood, urine, swabs, etc.) and testing the pools for the presence of disease. When the proportion of diseased individuals is small, group testing can greatly reduce the number of tests needed to screen a population. Statistical research in group testing has traditionally focused on applications for a single disease. However, blood service organizations and large-scale disease surveillance programs are increasingly moving towards the use of multiplex assays, which measure multiple disease biomarkers at once. Tebbs and others (2013, Two-stage hierarchical group testing for multiple infections with application to the Infertility Prevention Project. Biometrics69, 1064-1073) and Hou and others (2017, Hierarchical group testing for multiple infections. Biometrics73, 656-665) were the first to examine hierarchical group testing case identification procedures for multiple diseases. In this article, we propose new non-hierarchical procedures which utilize two-dimensional arrays. We derive closed-form expressions for the expected number of tests per individual and classification accuracy probabilities and show that array testing can be more efficient than hierarchical procedures when screening individuals for multiple diseases at once. We illustrate the potential of using array testing in the detection of chlamydia and gonorrhea for a statewide screening program in Iowa. Finally, we describe an R/Shiny application that will help practitioners identify the best multiple-disease case identification algorithm.

Pragmatic, double-blind, randomised trial evaluating the impact of red blood cell donor sex on recipient mortality in an academic hospital population: the innovative Trial Assessing Donor Sex (iTADS) protocol

INTRODUCTION

With over 1 million units of blood transfused each year in Canada, their use has a significant clinical and economic impact on our health system. Adequate screening of blood donors is important to ensure the safety and clinical benefit of blood products. Some adverse transfusion reactions have been shown to be related to donor factors (eg, lung injury), whereas other adverse outcomes have been theoretically related to donor factors (mortality and infection). Our clinical trial will test whether male donor blood leads to a greater benefit for transfusion recipients compared with female donor blood.

METHODS AND ANALYSIS

We have designed a pragmatic, double-blind, randomised trial that will allocate transfusion recipients to receive either male-only or female-only donor transfusions. We will enrol 8850 adult patients requiring at least one transfusion at four sites over an approximate 2-year period. Randomisation and allocation will occur in the blood bank prior to release of the units of blood for transfusion. Our primary outcome is mortality. An intent-to-treat analysis will be applied using all randomised and transfused patients. The principal analysis will be a survival analysis comparing the time from randomisation to death between patients allocated to male donor red blood cells (RBCs) and female donor RBCs.

ETHICS AND DISSEMINATION

Approval has been obtained from research ethics boards of all involved institutions, as well as from privacy offices of Canadian Blood Services, Institute for Clinical Evaluative Science and The Ottawa Hospital Data Warehouse. Our findings will be published in peer-reviewed journals and presented at relevant stakeholder conferences and meetings.

TRIAL REGISTRATION NUMBER

NCT03344887; Pre-results.

The impact of tranexamic acid on administration of red blood cell transfusions for resection of colorectal liver metastases

BACKGROUND

Red blood cell transfusions (RBCT) remain a concern for patients undergoing hepatectomy. The effect of tranexamic acid (TXA), an anti-fibrinolytic, on receipt of RBCT in colorectal liver metastases (CRLM) resection was examined.

METHODS

Hepatectomies for CRLM over 2009-2014 were included. Primary outcome was 30-day receipt of RBCT. Secondary outcomes were 30-day major morbidity (Clavien-Dindo III-V) and 90-day mortality. Multivariable modelling examined the adjusted association between TXA and outcomes.

RESULTS

Of 433 included patients, 146 (34%) received TXA. TXA patients were more likely to have inflow occlusion (41.8% vs. 23.1%; p < 0.01) and major hepatectomies (56.1% vs. 45.6%; p = 0.0193). TXA was independently associated with lower risk of RBCT (Relative risk (RR) 0.59; 95% confidence interval (95%CI): 0.42-0.85), but not with 30-day major morbidity (adjusted RR 1.02; 95%CI: 0.64-1.60) and 90-day mortality (univariable RR 0.99; 95%CI: 0.95-1.03).

CONCLUSION

Intraoperative TXA was associated with a 41% reduction in risk of 30 -day receipt of RBCT after hepatectomy for CRLM. This finding is important to potentially improve healthcare resource allocation and patient outcomes. Pending further evidence, intraoperative TXA may be an effective method of reducing RBCT in hepatectomy for CRLM.

Estimating the incidence of HIV infection in repeat blood donors with low average donation frequency

BACKGROUND

The standard approach to estimating HIV incidence in repeat blood donors includes only donors who made two or more donations in an estimation interval. In China and some other countries, large proportions of repeat donors donate only once in a 1- or 2-year interval. The standard approach may not represent risk among all repeat donors in these areas. Two approaches to including all repeat donors in the incidence estimate were evaluated in a simulation study.

STUDY DESIGN AND METHODS

Under one approach, a donor infected at the first donation contributes a partial case to incidence that equals the proportion of time since the preceding donation that is in the estimation interval. Under the other, that donor contributes a full case if at least half the time since the previous donation is in the estimation interval and nothing otherwise. Infections identified at the second or subsequent donations in the interval contribute full cases as usual. The simulations involved proportions with single donations of 11% to 65% combined with a variety of patterns of rising, falling, or constant incidence.

RESULTS

The partial-case approach was unbiased under more test conditions than the whole-case approach and exhibited smaller bias when both were biased. Under both approaches, bias >10% occurred only when rates of single donations >50% were combined with large changes in incidence over time.

CONCLUSION

The partial-case approach performed better than the whole-case approach. The conditions producing bias >10% are so extreme that they are unlikely to be encountered in the field.

Liver disease referrals to an urban, hospital-based hepatology outpatient clinic over the past 25 years

Background

Additional hepatologists are required to manage the rapidly increasing number of patients with liver disease. One disincentive to trainees considering a career in hepatology is the longstanding perception that outpatient hepatology consists largely of managing patients with alcohol‐induced liver disease (ALD).

Objectives

To document the types of liver diseases and changes in liver disease referrals to an urban outpatient liver disease clinic over the past 25 years.

Methods

The nature of the liver disorder, age, gender, and socioeconomic status of patients referred to an urban, hospital‐based, liver diseases outpatient program were documented from 1992 to 2017. Joinpoint analysis was performed to identify significant trends in referral prevalence rates of various disorders.

Results

In 1992/1993, hepatitis C virus (HCV), followed by hepatitis B virus (HBV), “other”, non‐alcoholic fatty liver disease (NAFLD), and primary biliary cholangitis (PBC) were the most common underlying liver diseases in referred patients (39, 36, 12, 4.5, and 3.5% respectively), whereas in 2016/2017, NAFLD, HBV, HCV, “other,” and ALD were most common (60, 15, 12, 8.7, and 3.3%, respectively). Aside from NAFLD referrals, which consistently increased over the 25‐year period, the prevalence of all other liver disease referrals fluctuated but generally declined. Recently referred patients were significantly older (38 ± 13 years in 1992/1993 and 49 ± 15 years in 2016/2017, P < 0.0001), while gender and socioeconomic status have not changed.

Conclusions

Hepatology is a diverse, dynamic subspecialty where ALD continues to constitute less than 5% of all patient referrals.

The evolving blood donor deferral policy for men who have sex with men: impact on the risk of HIV transmission by transfusion in France

BACKGROUND

Blood donation deferral for men who have sex with men (MSM) in France was reduced from permanent to 12 months in July 2016. To inform a further reduction of the deferral period, an HIV risk assessment was conducted with two scenarios: S1, 4-month deferral; S2, 4-month deferral only in the case of more than one sexual partner (i.e., similar to other blood donors).

METHODS

Baseline HIV residual risk (RR) was calculated from July 2016 to December 2017, using the Incidence Rate-Window Period method. The impact of both scenarios on RR was assessed using data from surveys on MSM and blood donors, to estimate 1) the number of additional MSM expected to donate in each scenario and 2) HIV incidence among these donors.

RESULTS

Baseline HIV RR was estimated at 1 in 6,380,000 donations. For S1, an additional 733 MSM donors, and an additional 0.09 HIV-positive donations were estimated, yielding an unchanged RR of 1 in 6,300,000. For S2, these numbers were estimated at 3102 and 3.92, respectively, yielding an RR of 1 in 4,300,000. Sensitivity analyses showed that, under worst-case assumptions, the RR would equal 1 in 6,225,000 donations for S1 and 1 in 3,000,000 for S2.

CONCLUSION

For both scenarios, the HIV RR remains very low. For S1, the risk is identical to the baseline RR. For S2, it is 1.5 times higher, and sensitivity analysis shows that this estimate is less robust than for S1. The French Minister of Health announced that S1 will be implemented in April 2020.

The Behavior of the Type of Peritoneal Transport in the Inflammatory and Oxidative Status in Adults Under Peritoneal Dialysis

Peritoneal dialysis (PD) is an alternative for managing the end-stage renal disease (ESRD). The peritoneal membrane (PM) is not just a membrane that passively responds to diffusion and convection. The characteristics of PM result in the peritoneal equilibrium test (PET) and with this test is possible to obtain the type of peritoneal transport (PT). The patient on PD can be classified in different types of PT as; Low, Low Average, High Average, and High. The aim of the study was to compare the inflammatory cytokines, oxidants, antioxidants, and oxidative DNA damage markers in the different types of PT. A cross-sectional analytical study of 77 adult PD patients was performed. Levels of lipoperoxides (LPO) were higher in all types of PT vs. healthy volunteer controls (HC) (p < 0.0001). Nitric oxide (NO) levels were found significantly down-regulated in all types of PT (p < 0.0001). The activity of the superoxide dismutase enzyme (SOD) was found to be significantly increased in all types of PT vs. the HC (p < 0.0001). The levels of the DNA repair enzyme were found to be decreased in all types of PT. The levels of the pro-inflammatory cytokines TNF-α, IL-6, the marker of oxidative DNA damage, 8-IP and the total antioxidant capacity (TAC) were all significantly decreased, contrary to the levels in HC, possibly by the clearance in the dialysis fluid in all types of PT or due to down-regulation of their expression. In conclusion, we found significant changes in markers of inflammation, oxidative stress, and oxidative damage to DNA in all types of PT; Low, low average, high average, and high PT in the values of D/P creatinine at 4 h compared to HC.

Prevalence, incidence and residual risk of transfusion-transmitted HBV infection before and after the implementation of HBV-NAT in northern Brazil

Background

Nucleic acid testing (NAT) for virus detection during blood screening has helped to prevent transfusion-transmitted infections worldwide. In northern Brazil, NAT was implemented in 2012 for HIV and HCV and more recently, in January 2015, the screening for HBV was included and currently used concomitant with serological tests (HBsAg and anti-HBc). This study aims to evaluate the prevalence and the incidence of HBV infection among voluntary blood donors at ten regional blood centers of HEMOPA Foundation in Pará state and to compare the residual risk of transfusion-transmitted HBV infection before and after the Brazilian HBV-NAT implementation.

Methods

The prevalence (restricted to first time donors- FT) and seroconversion rate (restricted to repeat donors- RP) of HBV were calculated based on rates of confirmed positive samples. Residual risk was based on the incidence and window period (WP) model described by Schreiber and coauthors. Logistic and Poisson regression were used in the statistical analysis by SPSS v20.0. A p value <0.05 was considered statistically significant.

Results

HBV prevalence in the periods before and after the implementation of HBV-NAT were 247 and 251 per 100,000 donations, respectively. Seroconversion rates were 114 and 122 per 100,000 donations in the two periods, respectively. The residual risk (RR) for HBV decreased significantly in the posterior period to the HBV-NAT implementation, when compared to RR before implementation, with a reduction of 1:144,92 to 1:294,11 donations (p <0,001).

Conclusions

The RR to HBV decreased after the implementation of HBV-NAT, increasing significantly the transfusional security in the North region of Brazil at HEMOPA Foundation.

Transfusion Practices Among General Surgeons at a Tertiary Care Center: a Survey Based Study

INTRODUCTION

Blood transfusion practices affect both patient's outcomes and utilization of institutional resources. Evidence shows that liberal blood transfusion has a detrimental effect on patient's outcome. A restrictive approach of blood transfusion is recommended by current clinical guidelines.

AIM

The aim of this study was to evaluate the attitudes, knowledge, and practices of general surgery (GS) staff and residents regarding peri-operative blood transfusion and anemia management.

MATERIAL AND METHODS

A self-administered, web-based questionnaire was developed, and its link was sent to the emails of all general surgeons at King Abdul-Aziz University Hospital (KAUH), Jeddah city, Saudi Arabia. The questionnaire included four parts: 1) background of surgeons; 2) preoperative assessment and management of anemia; 3) post-operative blood transfusion and alternatives; and 4) enablers and barriers.

RESULTS

56 surgeons responded to the questionnaire. We found variations in blood transfusion practices, notably the hemoglobin threshold. For stable non-cardiac cases, 7 g/dL was considered the threshold by 50% of respondents. For stable patients with past cardiac disease, a higher threshold was chosen by most (9 g/dL by 43% and 10 gm/dL by 21%). Most respondents believed that transfusion had no effect on the risk of survival (73%) and on the risk of cancer recurrence (55%) after oncologic surgical resection. Recognized facilitators were the availability of scientific evidence (84%), medicolegal concerns (57%), preference (52%), and institutional protocols (50%).

CONCLUSION

Although current clinical guidelines recommend a restrictive transfusion practice, most respondents tended to over-order blood for elective procedures and were not aware of the potential complications of liberal blood transfusion. To implement the restrictive transfusion policies, health institutions should improve the awareness of surgeons and incorporate a strong supporting evidence in formulating local institutional guidelines.

Group testing case identification with biomarker information

Screening procedures for infectious diseases, such as HIV, often involve pooling individual specimens together and testing the pools. For diseases with low prevalence, group testing (or pooled testing) can be used to classify individuals as diseased or not while providing considerable cost savings when compared to testing specimens individually. The pooling literature is replete with group testing case identification algorithms including Dorfman testing, higher-stage hierarchical procedures, and array testing. Although these algorithms are usually evaluated on the basis of the expected number of tests and classification accuracy, most evaluations in the literature do not account for the continuous nature of the testing responses and thus invoke potentially restrictive assumptions to characterize an algorithm's performance. Commonly used case identification algorithms in group testing are considered and are evaluated by taking a different approach. Instead of treating testing responses as binary random variables (i.e., diseased/not), evaluations are made by exploiting an assay's underlying continuous biomarker distributions for positive and negative individuals. In doing so, a general framework to describe the operating characteristics of group testing case identification algorithms is provided when these distributions are known. The methodology is illustrated using two HIV testing examples taken from the pooling literature.

The impact of perioperative blood transfusions on short-term outcomes following hepatectomy

Background

Bleeding and need for red blood cell transfusions (RBCT) remain a significant concern with hepatectomy. RBCT carry risk of transfusion-related immunomodulation that may impact post-operative recovery. This study soughs to assess the association between RBCT and post-hepatectomy morbidity.

Methods

Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) registry, we identified all adult patients undergoing elective hepatectomy over 2007-2012. Two exposure groups were created based on RBCT. Primary outcomes were 30-day major morbidity and mortality. Secondary outcomes included 30-day system-specific morbidity and length of stay (LOS). Relative risks (RR) with 95% confidence interval (95% CI) were computed using regression analyses. Sensitivity analyses were conducted to understand how missing data might have impacted the results.

Results

A total of 12,180 patients were identified. Of those, 11,712 met inclusion criteria, 2,951 (25.2%) of whom received RBCT. Major morbidity occurred in 14.9% of patients and was strongly associated with RBCT (25.3% vs. 11.3%; P<0.001). Transfused patients had higher rates of 30-day mortality (5.6% vs. 1.0%; P<0.0001). After adjustment for baseline and clinical characteristics, RBCT was independently associated with increased major morbidity (RR 1.80; 95% CI: 1.61-1.99), mortality (RR 3.62; 95% CI: 2.68-4.89), and 1.29 times greater LOS (RR 1.29; 95% CI: 1.25-1.32). Results were robust to a number of sensitivity analyses for missing data.

Conclusions

Perioperative RBCT for hepatectomy was independently associated with worse short-term outcomes and prolonged LOS. These findings further the rationale to focus on minimizing RBCT for hepatectomy, when they can be avoided.

The current incidence, prevalence, and residual risk of hepatitis B viral infections among voluntary blood donors in China

BACKGROUND

There are few data available on the prevalence, incidence, and residual risk of transfusion-transmitted HBV (TT-HBV) infections among Chinese blood donors. This study investigated the demographic characteristics of blood donors, as well as the prevalence, incidence, and residual risk (RR) of TT-HBV infections in six large blood centers in different regions of China.

METHODS

The demographic characteristics and HBV screening test results of blood donors from six blood centers in different regions in China were collected and analyzed. The hepatitis B surface antigen (HBsAg) yield approach was used to estimate the incidence of HBV. Then, the RR of TT-HBV infections was evaluated using the incidence-window period model.

RESULTS

The majority of donors were between 18 and 35 years old (including 35), with the exception of the Changzhi Blood Center where a majority of donors were between 35 and 55 years old (including 55). The prevalences of HBV were 0.13%, 0.078%, 0.16%, 0.07%, 0.20%, 0.25% in Hefei, Dalian, Changzhi, Kaifeng, Mianyang and Fujian, respectively. The estimated corresponding incidences were 213.44, 161.59, 989.80, 278.05, 125.31 and 352.19 per 10⁵ person-years. Using an infectious window period of 59 days, the RR for HBV was estimated to be 34.14, 25.85, 158.35, 44.48, 20.04 and 56.35 per 10⁵ person-years in Hefei, Dalian, Changzhi, Kaifeng, Mianyang and Fujian, respectively.

CONCLUSION

Despite the introduction of more sensitive assays in blood screening, our data revealed that the current residual risk of TT-HBV infection was still high (overall 56.53 per 10⁵ py). A continuous monitoring of the residual risk of transfusion-transmitted infections is crucial for safe blood management.

Residual risk of transmission of human immunodeficiency virus and hepatitis C virus infections by blood transfusion in northern Brazil

BACKGROUND

Nucleic acid test (NAT) blood screening for human immunodeficiency virus (HIV) and hepatitis C virus (HCV) was introduced in northern Brazil in July 2012. There are several Brazilian articles that have evaluated transfusion transmission risks for HIV and HCV. However, to our knowledge, this article is the first to evaluate the impact of HIV and HCV NAT implementation for blood screening in northern Brazil. The aim of this study was to determine the prevalence and incidence rates of HIV and HCV among blood donors and to compare the residual risk of transfusion transmission of these infections, before (2009-2011) and after (2012-2014) NAT implementation.

STUDY DESIGN AND METHODS

HIV and HCV prevalence and incidence were calculated based on rates of confirmed positive samples. Residual risk estimates were based on the incidence and window model described previously. Logistic and Poisson regressions were used in the statistical analysis. A p value of not more than 0.05 was considered significant.

RESULTS

HIV and HCV prevalence were 209.9 and 66.3 per 100,000 donations, respectively. Residual risk for HIV and HCV decreased significantly throughout the two study periods, mainly for HCV in which the reduction was one in 169,492 to one in 769,231 donations. For HIV, the decrease was one in 107,527 to one in 769,231 donations. HIV and HCV incidence rates were 21.13 and 3.06 per 100,000 persons/year before NAT and 14.03 and 2.65 per 100,000 persons/year after NAT.

CONCLUSION

The HIV and HCV NAT implementation significantly increased the transfusion safety in northern Brazil, bringing benefits to recipients due to better quality of blood products produced.

Residual risk of HIV, HCV and HBV in Canada

BACKGROUND

Residual risk is estimated as the product of the incidence and the infectious window period, the time during which a blood donation could be infectious but the assay may not detect it. In 2011 nucleic acid multiplex testing (MPX) was implemented in 6 unit minipools (previously 24 unit minipools). MPX also included hepatitis B (HBV) NAT for the first time (complementing HBsAg screening) in addition to HIV-1 and hepatitis C (HCV) as before. We aimed to estimate window period risk-day equivalents for MPX, and the residual risk of viral infections in blood donations updated to reflect current incidence and testing.

METHODS

Transmissible disease conversions of repeat donations to Canadian Blood Services within the three-year period 2012-2014 divided by person-years estimated incidence for HIV, HCV and HBV (adjusted for transient viremia). Window period risk-day equivalents for MPX were estimated using a published method. Residual risk was the product of incidence and window period risk-day equivalents. 95% confidence intervals were estimated using Monte Carlo simulation of the window period risk-day equivalents and the incidence density 95% confidence intervals.

RESULTS

The incidence rate per 100,000 person years for HIV was 0.28, HCV 1.0 and HBV 0.26. The residual risk of HIV was 1 per 21.4 million donations, HCV 1 per 12.6 million donations and HBV 1 per 7.5 million donations.

CONCLUSION

The residual risk of infection is very low, similar to 2006-2009. The safety benefit of further shortening of the infectious window period is below the threshold to quantify.

Quality Assessment of Established and Emerging Blood Components for Transfusion

Blood is donated either as whole blood, with subsequent component processing, or through the use of apheresis devices that extract one or more components and return the rest of the donation to the donor. Blood component therapy supplanted whole blood transfusion in industrialized countries in the middle of the twentieth century and remains the standard of care for the majority of patients receiving a transfusion. Traditionally, blood has been processed into three main blood products: red blood cell concentrates; platelet concentrates; and transfusable plasma. Ensuring that these products are of high quality and that they deliver their intended benefits to patients throughout their shelf-life is a complex task. Further complexity has been added with the development of products stored under nonstandard conditions or subjected to additional manufacturing steps (e.g., cryopreserved platelets, irradiated red cells, and lyophilized plasma). Here we review established and emerging methodologies for assessing blood product quality and address controversies and uncertainties in this thriving and active field of investigation.

A comparison of methods for estimating the incidence of human immunodeficiency virus infection in repeat blood donors

BACKGROUND

The incidence of human immunodeficiency virus (HIV) in repeat blood donors has been estimated using seven methods. Although incidence is always calculated as cases per person-time, approaches to selecting cases and calculating person-time vary. Incidence estimates have not been compared among methods.

STUDY DESIGN AND METHODS

The seven methods were compared in a simulation study. Because three methods used information from donations made before an estimation interval, 8 years of donation and infection history were simulated, and Years 7 and 8 were treated as the estimation interval for all methods. An exponential random variate was assigned to each donor to simulate the time to infection. Infection risk was constant over 8 years in one scenario but increased at various rates in seven other scenarios. The infection risk scenarios were combined with four mixes of donation frequency to generate 32 test conditions.

RESULTS

Three methods produced biased estimates under all conditions. Three other methods were biased under most conditions. Bias from most methods increased as donation frequency declined. The single method that consistently produced unbiased estimates was the only method that involved the standard epidemiological approach of tabulating all interdonation intervals (IDIs) within the estimation interval. Bias was eliminated from one of the consistently biased methods by a simple modification that involved the average IDI in a sample of donors.

CONCLUSION

The standard epidemiological approach is recommended if required data are available. Otherwise, the modified method involving the estimated average IDI should be considered. Investigators should use caution when comparing incidence estimates among studies that use different estimation methods or donation frequencies.

Estimating the prevalence of multiple diseases from two-stage hierarchical pooling

Testing protocols in large-scale sexually transmitted disease screening applications often involve pooling biospecimens (e.g., blood, urine, and swabs) to lower costs and to increase the number of individuals who can be tested. With the recent development of assays that detect multiple diseases, it is now common to test biospecimen pools for multiple infections simultaneously. Recent work has developed an expectation-maximization algorithm to estimate the prevalence of two infections using a two-stage, Dorfman-type testing algorithm motivated by current screening practices for chlamydia and gonorrhea in the USA. In this article, we have the same goal but instead take a more flexible Bayesian approach. Doing so allows us to incorporate information about assay uncertainty during the testing process, which involves testing both pools and individuals, and also to update information as individuals are tested. Overall, our approach provides reliable inference for disease probabilities and accurately estimates assay sensitivity and specificity even when little or no information is provided in the prior distributions. We illustrate the performance of our estimation methods using simulation and by applying them to chlamydia and gonorrhea data collected in Nebraska. Copyright © 2016 John Wiley & Sons, Ltd.

The impact of blood transfusion on perioperative outcomes following gastric cancer resection: an analysis of the American College of Surgeons National Surgical Quality Improvement Program database

BACKGROUND

Red blood cell transfusions (RBCT) carry risk of transfusion-related immunodulation that may impact postoperative recovery. This study examined the association between perioperative RBCT and short-term postoperative outcomes following gastrectomy for gastric cancer.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program database, we compared outcomes of patients (transfused v. nontransfused) undergoing elective gastrectomy for gastric cancer (2007-2012). Outcomes were 30-day major morbidity, mortality and length of stay. The association between perioperative RBCT and outcomes was estimated using modified Poisson, logistic, or negative binomial regression.

RESULTS

Of the 3243 patients in the entire cohort, we included 2884 patients with nonmissing data, of whom 535 (18.6%) received RBCT. Overall 30-day major morbidity and mortality were 20% and 3.5%, respectively. After adjustment for baseline and clinical characteristics, RBCT was independently associated with increased 30-day mortality (relative risk [RR] 3.1, 95% confidence interval [CI] 1.9-5.0), major morbidity (RR 1.4, 95% CI 1.2-1.8), length of stay (RR 1.2, 95% CI 1.1-1.2), infections (RR 1.4, 95% CI 1.1-1.6), cardiac complications (RR 1.8, 95% CI 1.0-3.2) and respiratory failure (RR 2.3, 95% CI 1.6-3.3).

CONCLUSION

Red blood cell transfusions are associated with worse postoperative short-term outcomes in patients with gastric cancer. Blood management strategies are needed to reduce the use of RBCT after gastrectomy for gastric cancer.

Understanding Perioperative Transfusion Practices in Gastrointestinal Surgery-a Practice Survey of General Surgeons

BACKGROUND

Despite guidelines recommending restrictive red blood cell transfusion (RBCT) strategies, perioperative transfusion practices still vary significantly. To understand the underlying mechanisms that lead to gaps in practice, we sought to assess the attitudes of surgeons regarding the perioperative management of anemia and use of RBCT in patients having gastrointestinal surgery.

METHODS

We conducted a self-administered Web-based survey of general surgery staff and residents, in a network of eight academic institutions at the University of Toronto. We developed a questionnaire using a systematic approach of items generation and reduction. We tested face and content validity and test-retest reliability. We administered the survey via emails, with planned reminders.

RESULTS

Total response rate was 48.1 % (62/125). Half (51.0 %) of respondents stated that they were unlikely to conduct a preoperative anemia work-up. About 54.0 % reported ordering preoperative oral iron supplementation for anemia. Most respondents indicated using a 70 g/L hemoglobin trigger (92.0 %) for transfusion. Factors increasing thresholds above 70 g/L included cardiac comorbidity (58.0 %), acute cardiac disease (94.0 %), symptomatic anemia (68.0 %), and suspected bleeding (58.0 %). With those factors, the transfusion threshold often increased above 90 g/L. Respondents perceived RBCTs to increase the postoperative morbidity (62 %), but not to impact the mortality (48 %) and cancer recurrence (52 %). Institutional protocols (68.0 %), blood conservation clinics (44.0 %), and clinical practice guidelines (84.0 %) were believed to encourage restrictive use of RBCTs.

CONCLUSION

Self-reported perioperative transfusion practices for GI surgery are heterogeneous. Few respondents investigated preoperative anemia. Stated use of RBCT indications varied from recommendations in published guidelines for patients with symptomatic anemia. Establishing team consensus and implementing local blood management guidelines appear necessary to improve uptake of evidence-based recommendations.

A decision model and cost analysis of intra-operative cell salvage during hepatic resection

BACKGROUND

Intraoperative cell salvage (ICS) can reduce allogeneic transfusions but with notable direct costs. This study assessed whether routine use of ICS is cost minimizing in hepatectomy and defines a subpopulation of patients where ICS is most cost minimizing based on patient transfusion risk.

METHODS

A decision model from a health systems perspective was developed to examine adoption and non-adoption of ICS use for hepatectomy. A prospectively maintained database of hepatectomy patients provided data to populate the model. Probabilistic sensitivity analysis was used to determine the probability of ICS being cost-minimizing at specified transfusion risks. One-way sensitivity analysis was used to identify factors most relevant to institutions considering adoption of ICS for hepatectomies.

RESULTS

In the base case analysis (transfusion risk of 28.8%) the probability that routine utilization of ICS is cost-minimizing is 64%. The probability that ICS is cost-minimizing exceeds 50% if the patient transfusion risk exceeds 25%. The model was most sensitive to patient transfusion risk, variation in costs of allogeneic blood, and number of appropriate cases the device could be used for.

CONCLUSIONS

ICS is cost-minimizing for routine use in liver resection, particularly when used for patients with a risk of transfusion of 25% or greater.

Blood-Borne Pathogens: A Canadian Blood Services Centre for Innovation Symposium

Testing donations for pathogens and deferring selected blood donors have reduced the risk of transmission of known pathogens by transfusion to extremely low levels in most developed countries. Protecting the blood supply from emerging infectious threats remains a serious concern in the transfusion medicine community. Transfusion services can employ indirect measures such as surveillance, hemovigilance, and donor questioning (defense), protein-, or nucleic acid based direct testing (detection), or pathogen inactivation of blood products (destruction) as strategies to mitigate the risk of transmission-transmitted infection. In the North American context, emerging threats currently include dengue, chikungunya, and hepatitis E viruses, and Babesia protozoan parasites. The 2003 SARS and 2014 Ebola outbreaks illustrate the potential of epidemics unlikely to be transmitted by blood transfusion but disruptive to blood systems. Donor-free blood products such as ex vivo generated red blood cells offer a theoretical way to avoid transmission-transmitted infection risk, although biological, engineering, and manufacturing challenges must be overcome before this approach becomes practical. Similarly, next generation sequencing of all nucleic acid in a blood sample is currently possible but impractical for generalized screening. Pathogen inactivation systems are in use in different jurisdictions around the world, and are starting to gain regulatory approval in North America. Cost concerns make it likely that pathogen inactivation will be contemplated by blood operators through the lens of health economics and risk-based decision making, rather than in zero-risk paradigms previously embraced for transfusable products. Defense of the blood supply from infectious disease risk will continue to require innovative combinations of surveillance, detection, and pathogen avoidance or inactivation.

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A symposium on blood-borne pathogens was held September 26, 2015, in Toronto, Canada.

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Transmission-transmitted infections remain a threat to the blood supply.

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The residual risk from established pathogens is small; emerging agents are a concern.

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Next generation sequencing and donor-free blood are not yet practical approaches.

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Pathogen inactivation technology is being increasingly used around the world.

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Health economic concerns will likely guide future advances in this area.

Effect of Blood Donor Characteristics on Transfusion Outcomes: A Systematic Review and Meta-Analysis

Optimal selection of blood donors is critical for ensuring the safety of blood products. The current selection process is concerned principally with the safety of the blood donor at the time of donation and of the recipient at the time of transfusion. Recent evidence suggests that the characteristics of the donor may affect short- and long-term transfusion outcomes for the transfused recipient. We conducted a systematic review with the primary objective of assessing the association between blood donor characteristics and red blood cell (RBC) transfusion outcomes. We searched MEDLINE, EMBASE, and Cochrane Central databases and performed manual searches of top transfusion journals for all available prospective and retrospective studies. We described study characteristics, methodological quality, and risk of bias and provided study-level effect estimates and, when appropriate, pooled estimates with 95% confidence intervals using the Mantel-Haenszel or inverse variance approach. The overall quality of the evidence was graded using Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. From 6121 citations identified by our literature search, 59 studies met our eligibility criteria (50 observational, 9 interventional). We identified the evaluation of association of 17 donor characteristics on RBC transfusion outcome. The risk of bias and confounding of the included studies was high. The quality of evidence was graded as very low to low for all 17 donor characteristics. Potential associations were observed for donor sex with reduced survival at 90 days and 6 months in male recipients that receive donated blood from females (hazard ratio 2.60 [1.09, 6.20] and hazard ratio 2.40 [1.10, 5.24], respectively; n = 1), Human Leukocyte Antigen - antigen D Related (HLA-DR) selected transfusions (odds ratio [OR] 0.39 [0.15, 0.99] for the risk of transplant alloimmunization, n = 9), presence of antileukocyte antibodies (OR 5.84 [1.66, 20.59] for risk of transfusion-related acute lung injury, n = 4), and donor RBC antigens selection (OR 0.20 [0.08, 0.52] for risk of alloimmunization, n = 4). Based on poor quality evidence, positive antileukocyte antibodies, female donor to male recipients, HLA-DR selected RBC transfusion, or donor RBC antigen selection may affect RBC transfusion outcome. Our findings that donor characteristics may be associated with transfusion outcomes warrant establishing vein-to-vein data infrastructure to allow for large robust evaluations. PROSPERO registration number: CRD42013006726.

Impact of a 5-year deferral from blood donation for men who have sex with men

BACKGROUND

The deferral for men who have sex with men (MSM) changed from a permanent deferral since 1977 to a 5-year deferral on July 22, 2013, in Canada. We assessed the impact on safety and adequacy of the blood supply at Canadian Blood Services.

STUDY DESIGN AND METHODS

Human immunodeficiency virus (HIV) rates were monitored from January 1, 2010, to July 21, 2015. Risk factors were assessed in notification interviews. Anonymous online surveys of male whole blood donors assessed compliance before and after implementation.

RESULTS

HIV rates were 0.2, 0.5, and 0.51 per 100,000 donations in 2010 to 2012; they were 0.54 and 0.22 in the first and second years after implementation (p = 0.8). Of four male HIV-positive donors after implementation, three denied risk factors and one knew he had HIV. Before implementation 9669 of 19,437 (49.7%) donors participated in the survey, and after implementation, 6881 of 18,934 (36.3%). Before implementation 0.67% of male donors were noncompliant, and after implementation, 0.44%. There was no difference before versus after implementation in male donors with MSM history in the past 5 years (0.37% vs. 0.43%, p = 0.54). After implementation, eligible MSM donors increased (0.42% vs. 0.66%, p = 0.04), with approximately 500 more donors in 2014.

CONCLUSION

Implementation of a 5-year deferral for MSM had no impact on HIV rates in 2 years of postimplementation monitoring. Donor compliance improved after implementation due to MSM donors who were previously ineligible becoming eligible. There was no change in the percentage of male donors with recent male partners but there was a modest increase in eligible MSM in the donor pool.

The impact of peri-operative blood transfusions on post-pancreatectomy short-term outcomes: an analysis from the American College of Surgeons National Surgical Quality Improvement Program

BACKGROUND

Peri-operative red blood cell transfusions (RBCT) may induce transfusion-related immunomodulation and impact post-operative recovery. This study examined the association between RBCT and post-pancreatectomy morbidity.

METHODS

Using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) registry, patients undergoing an elective pancreatectomy (2007-2012) were identified. Patients with missing data on key variables were excluded. Primary outcomes were 30-day post-operative major morbidity, mortality, and length of stay (LOS). Unadjusted and adjusted relative risks (RR) with a 95% confidence interval (95%CI) were computed using modified Poisson, logistic, or negative binomial regression, to estimate the association between RBCT and outcomes.

RESULTS

The database included 21 132 patients who had a pancreatectomy during the study period. Seventeen thousand five hundred and twenty-three patients were included, and 4672 (26.7%) received RBCT. After adjustment for baseline and clinical characteristics, including comorbidities, malignant diagnosis, procedure and operative time, RBCT was independently associated with increased major morbidity (RR 1.49; 95% CI: 1.39-1.60), mortality (RR 2.19; 95%CI: 1.76-2.73) and LOS (RR 1.27; 95%CI 1.24-1.29).

CONCLUSION

Peri-operative RBCT for a pancreatectomy was independently associated with worse short-term outcomes and prolonged LOS. Future studies should focus on the impact of interventions to minimize the use of RBCT after an elective pancreatectomy.

Treatment of Platelet Products with Riboflavin and UV Light: Effectiveness Against High Titer Bacterial Contamination

Contamination of platelet units by bacteria has long been acknowledged as a significant transfusion risk due to their post-donation storage conditions. Products are routinely stored at 22 °C on an agitating shaker, a condition that can promote bacterial growth. Although the total number of bacteria believed to be introduced into a platelet product is extremely low, these bacteria can multiply to a very high titer prior to transfusion, potentially resulting in serious adverse events. The aim of this study was to evaluate a riboflavin based pathogen reduction process against a panel of bacteria that have been identified as common contaminants of platelet products. This panel included the following organisms: S. epidermidis, S. aureus, S. mitis, S. pyogenes, S. marcescens, Y. enterocolitica, B. neotomae, B. cereus, E. coli, P. aeruginosa and K. pneumoniae. Each platelet unit was inoculated with a high bacterial load and samples were removed both before and after treatment. A colony forming assay, using an end point dilution scheme, was used to determine the pre-treatment and post-treatment bacterial titers. Log reduction was calculated by subtracting the post-treatment titer from the pre-treatment titer. The following log reductions were observed: S. epidermidis 4.7 log (99.998%), S. aureus 4.8 log (99.998%), S. mitis 3.7 log (99.98%), S. pyogenes 2.6 log (99.7%), S. marcescens 4.0 log (99.99%), Y. enterocolitica 3.3 log (99.95%), B. neotomae 5.4 log (99.9996%), B. cereus 2.6 log (99.7%), E. coli ≥5.4 log (99.9996%), P. aeruginosa 4.7 log (99.998%) and K. pneumoniae 2.8 log (99.8%). The results from this study suggest the process could help to lower the risk of severe adverse transfusion events associated with bacterial contamination.

The Impact of Perioperative Red Blood Cell Transfusions on Long-Term Outcomes after Hepatectomy for Colorectal Liver Metastases

BACKGROUND

Red blood cell transfusions (RBCTs) are associated with cancer recurrence following resection of colorectal cancer. Their impact after colorectal liver metastases (CRLM) resection remains debated. We sought to explore the association between perioperative RBCT and oncologic outcomes following resection of CRLM.

METHODS

We reviewed patients undergoing partial hepatectomy for CRLM from 2003 to 2012 at a single institution. Date of death was abstracted from a validated population-based cancer registry. Primary outcome was overall survival (OS). Secondary outcome was recurrence-free survival (RFS). Survivals were estimated using Kaplan-Meier methods and compared with log-rank test based on transfusion status. Cox regression analysis examined the association of RBCT with OS and RFS, while adjusting for age, preoperative chemotherapy, Clinical Risk Score, and period of treatment (2003-2007 vs. 2008-2012).

RESULTS

Among 483 patients, 27.5 % received RBCT. Ninety-day postoperative mortality was 4.8 %. At median follow-up of 33 (interquartile range 20.1-54.8) months, 5-year OS was inferior in transfused patients (45.9 vs. 61.0 %; p < 0.0001). Five-year RFS was decreased with RBCT (15.5 vs. 31.6 %; p < 0.0001). The difference persisted when considering only 90-day survivors for 5-year OS (53.1 vs. 61.9 %, p = 0.023) and RFS (15.6 vs. 31.6 %; p < 0.0001). After adjustment for prognostic factors, RBCT was independently associated with decreased OS (hazard ratio 2.24; 95 % confidence interval 1.60-3.15) and RFS (hazard ratio 1.71; 95 % confidence interval 1.28-2.28).

CONCLUSIONS

Perioperative RBCT is independently associated with decreased OS and RFS following hepatectomy for CRLM. Interventions to minimize and rationalize the use of RBCT for hepatectomy are warranted to mitigate this detrimental effect on long-term outcomes.

Inactivation of viruses in platelet and plasma products using a riboflavin-and-UV-based photochemical treatment

BACKGROUND

Multilayered blood safety programs reduce the risk of transfusion-transmitted diseases; however, there remains a risk of window period transmission of screened viruses and transmission of unscreened and emerging viruses from asymptomatic donors. To reduce this risk, a riboflavin-and-UV-light-based pathogen reduction process was evaluated against eight viral agents.

STUDY DESIGN AND METHODS

Riboflavin and UV light was evaluated against the following eight viral agents: encephalomyocarditis virus (EMC), hepatitis A virus (HAV), hepatitis C virus (HCV), influenza A (FLUAV), La Crosse virus (LACV), pseudorabies virus (PRV), sindbis virus (SINV), and vesicular stomatitis virus (VSV). Before treatment, a sample was removed to determine the product's initial viral load. After treatment the product's viral load was reevaluated and the log reduction was calculated.

RESULTS

Virus reduction after treatment with riboflavin and UV light is equivalent in platelet (PLT) and plasma units, as demonstrated by a 3.2-log reduction of EMC in plasma, PLTs, and PLT additive solution containing 35% plasma. Additionally, the following viral reductions values were observed: HAV 1.8 log, HCV at least 4.1 log, FLUAV at least 5.0 log, LACV at least 3.5 log, PRV 2.5 log, SINV 3.2 log, and VSV at least 6.3 log.

CONCLUSIONS

The results observed in this study suggest that treating PLT and plasma products with a riboflavin-and-UV-light-based pathogen reduction process could potentially eliminate window period transmission of screened viruses and greatly reduce the risk of transfusion transmission of unscreened viruses.

Clinical effects of blood donor characteristics in transfusion recipients: protocol of a framework to study the blood donor-recipient continuum

INTRODUCTION

When used appropriately, transfusion of red blood cells (RBCs) is a necessary life-saving therapy. However, RBC transfusions have been associated with negative outcomes such as infection and organ damage. Seeking explanations for the beneficial and deleterious effects of RBC transfusions is necessary to ensure the safe and optimal use of this precious resource. This study will create a framework to analyse the influence of blood donor characteristics on recipient outcomes.

METHODS AND ANALYSIS

We will conduct a multisite, longitudinal cohort study using blood donor data routinely collected by Canadian Blood Services, and recipient data from health administrative databases. Our project will include a thorough validation of primary data, the linkage of various databases into one large longitudinal database, an in-depth epidemiological analysis and a careful interpretation and dissemination of the results to assist the decision-making process of clinicians, researchers and policymakers in transfusion medicine. Our primary donor characteristic will be age of blood donors and our secondary donor characteristics will be donor-recipient blood group compatibility and blood donor sex. Our primary recipient outcome will be a statistically appropriate survival analysis post-RBC transfusion up to a maximum of 8 years. Our secondary recipient outcomes will include 1-year, 2-year and 5-year mortality; hospital and intensive care unit length of stay; rehospitalisation; new cancer and cancer recurrence rate; infection rate; new occurrence of myocardial infarctions and need for haemodialysis.

ETHICS AND DISSEMINATION

Our results will help determine whether we need to tailor transfusion based on donor characteristics, and perhaps this will improve patient outcome. Our results will be customised to target the different stakeholders involved with blood transfusions and will include presentations, peer-reviewed publications and the use of the dissemination network of blood supply organisations. We obtained approval from the Research Ethics boards and privacy offices of all involved institutions.

Evaluation of the appropriateness of frozen plasma usage after introduction of prothrombin complex concentrates: a retrospective study

BACKGROUND

Prothrombin complex concentrates (PCCs) can be used instead of frozen plasma (FP) transfusion to reverse the effect of warfarin. Audits have demonstrated over usage of FP transfusions even before the introduction of PCC. The objective of this study was to determine the appropriateness of current FP transfusion practice in the current era since the introduction of PCCs.

METHODS

A retrospective cohort study of consecutive patients receiving FP over 3 months was carried out. Each episode of FP use over a 24-h period was adjudicated independently by two reviewers as appropriate (consistent with Canadian/AABB guidelines), appropriate but inconsistent with guidelines or inappropriate. Discrepancies were resolved by a third reviewer. Use of FP to reverse warfarin was considered inappropriate. FP usage from previous years was assessed as baseline.

RESULTS

During the study period, 111 FP transfusions were administered. 74.8% of FP usage occurred in the ICU. The proportion of FP transfusions that were deemed appropriate, inconsistent yet appropriate or inappropriate were 33/89 (37.1%), 16/89 (18.0%) and 40/89 (44.9%), respectively, when use of FP for therapeutic plasma exchange was excluded. The most common reasons for inappropriate use were the absence of bleeding with an increased INR or warfarin reversal.

CONCLUSION

Our study is the first to audit FP transfusions in the post-PCC era in Canada. FP usage remains inappropriately high in INR prolongation without another indication or to reverse warfarin. Targeted interventions to reduce FP usage in the future should focus on the ICU and on education about warfarin reversal.

Hepatitis C surveillance in Canada

Background

Hepatitis C is a highly transmissible virus that can lead to chronic liver disease. It continues to be a major public health concern in Canada.

Objective

To describe surveillance trends of reported cases of Hepatitis C virus (HCV) in Canada by age and sex from 1991-2012.

Methods

Cases of HCV reported to the Canadian Notifiable Disease Surveillance System were compiled at the national level. As most reported cases are not differentiated by acute or chronic HCV infection status, presented results are based on total HCV cases. Time trends are provided from 1991-2012, with a more detailed examination of age and sex patterns from 2005-2012.

Results

The rate of reported HCV infection increased sharply from 1991 (the year it was first notifiable) until 1998, when the highest overall rate of 66.9 per 100,000 was observed. From that time until 2012, rates of reported cases decreased in both sexes, but remained consistently higher among males than females. In 2012, the overall rate of reported HCV infection was 29.3 per 100,000. In younger age groups, rates among females were marginally higher, while males in older age groups (30 and above) exhibited substantially higher rates.

Conclusion

This surveillance summary presents the longer-term trends in reported cases and corresponding rates of HCV in Canada using national surveillance data. Canada continues to experience a downward trend in HCV rates; however, the burden of infection will continue to increase as chronically infected individuals develop severe illness.

Estimating the residual risk for HIV, HCV and HBV in different types of platelet concentrates in Germany

BACKGROUND AND OBJECTIVES

We estimated and compared the residual risks due to window-period donations for pooled and apheresis platelets in Germany using a modification of a previously described statistical model. This model directly utilizes the reported interdonation intervals before a positive donation and reflects in this aspect the look-back procedures used in haemovigilance.

MATERIALS AND METHODS

Data from the German National Blood Donor Surveillance System for the years 2006-2012, including reports about donations from repeat donors with confirmed positive test results for HIV, HCV and HBV, were used to estimate the risk of undetected infectious units for both pooled and apheresis platelets.

RESULTS

Demographics of whole-blood and apheresis donors differed in age, gender, catchment area and interdonation interval. These differences impact on the prevalence and incidence of transfusion relevant infections and consequently the residual risk. The estimates for the residual risks for pooled and apheresis platelets were comparable. For HIV, there was no significant difference, for HCV apheresis platelets had a lower residual risk, whereas pooled platelets had a lower risk for undetected HBV infections.

CONCLUSION

These findings do not support calls for a shift to an apheresis platelets-only policy in Germany.

The proportion and trend of human immunodeficiency virus infections associated with men who have sex with men from Chinese voluntary blood donors: a systematic review and meta-analysis

BACKGROUND

Human immunodeficiency virus (HIV)-positive cases associated with men who have sex with men (MSM) have rapidly increased over the past years. The objective of this study is to comprehensively evaluate the proportions, changing trends, and geographical distribution of MSM-associated HIV cases from Chinese voluntary blood donors by systematically reviewing the available literature.

STUDY DESIGN AND METHODS

Major English and Chinese research databases were searched for studies reporting study locations, study years, the number of HIV infections among blood donors, and the number of HIV-positive donations associated with MSM in China. The proportion estimates were calculated; subgroup analyses and test for time trend were performed using software of comprehensive meta-analysis.

RESULTS

Thirty-four studies met eligibility criteria. The pooled proportion of HIV-positive donations associated with MSM from 2001 to 2012 was 36.5% (95% confidence interval, 29.6%-44.1%). The epidemic was found to be more severe in northeast and north China compared to south China (59.6%; 55.0% vs. 3.8%, respectively). The proportion showed a significantly increasing trend over the study period (10.3% in 2001-2005; 38.6% in 2006-2009; and 47.6% in 2010-2012; trend test chi-square = 16.42, p < 0.001).

CONCLUSION

The relatively high proportion of MSM- associated HIV-positive donors is of concern. Efficient and effective measures focused on public education and improving knowledge of blood safety are needed to prevent this at-risk population from seeking HIV testing through blood donation. It is also imperative to expand the scope of postdonation nucleic acid testing to shorten the window period to improve blood supply safety in China.

The impact of perioperative iron on the use of red blood cell transfusions in gastrointestinal surgery: a systematic review and meta-analysis

Perioperative anemia is common, yet detrimental, in surgical patients. However, red blood cell transfusions (RBCTs) used to treat anemia are associated with significant postoperative risks and worse oncologic outcomes. Perioperative iron has been suggested to mitigate perioperative anemia. This meta-analysis examined the impact of perioperative iron compared to no intervention on the need for RBCT in gastrointestinal surgery. We systematically searched Medline, Embase, Web of Science, Cochrane Central, and Scopus to identify relevant randomized controlled trials (RCTs) and nonrandomized studies (NRSs). We excluded studies investigating autologous RBCT or erythropoietin. Two independent reviewers selected the studies, extracted data, and assessed the risk of bias using the Cochrane tool and Newcastle-Ottawa scale. Primary outcomes were proportion of patients getting allogeneic RBCT and number of transfused patient. Secondary outcomes were hemoglobin change, 30-day postoperative morbidity and mortality, length of stay, and oncologic outcomes. A meta-analysis using random effects models was performed. The review was registered in PROSPERO (CRD42013004805). From 883 citations, we included 2 RCTs and 2 NRSs (n = 325 patients), all pertaining to colorectal cancer surgery. Randomized controlled trials were at high risk for bias and underpowered. One RCT and 1 NRS using preoperative oral iron reported a decreased proportion of patients needing RBCT. One RCT on preoperative intravenous iron and 1 NRS on postoperative PO iron did not observe a difference. Only 1 study revealed a difference in number of transfused patients. One RCT reported significantly increased postintervention hemoglobin. Among 3 studies reporting length of stay, none observed a difference. Other secondary outcomes were not reported. Meta-analysis revealed a trend toward fewer patients requiring RBCT with iron supplementation (risk ratio, 0.66 [0.42, 1.02]), but no benefit on the number of RBCT per patient (weighted mean difference, -0.91 [-1.61, -0.18]). Although preliminary evidence suggests that it may be a promising strategy, there is insufficient evidence to support the routine use of perioperative iron to decrease the need for RBCT in colorectal cancer surgery. Well-designed RCTs focusing on the need for RBCT and including long-term outcomes are warranted.

Effect of blood donor characteristics on transfusion outcomes: a protocol for systematic review and meta-analysis

BACKGROUND

Optimal selection of blood donors is of paramount importance in ensuring the safety of blood products. The current selection process is concerned principally with the safety of the blood donor and the safety of the patient that receives the blood. Recent evidence suggests that the characteristics of the donor may affect transfusion outcomes for the recipient.

METHODS

We will conduct a systematic review of the association between major blood donor characteristics and red blood cell (RBC) transfusion outcomes. The primary objective is to assess the association of blood donor characteristics and the risk of adverse short-term and long-term clinical outcomes after RBC transfusion. We will search MEDLINE, EMBASE, Cochrane Central databases, as well as perform manual searches of top transfusion medical journals for prospective and retrospective studies. Study characteristics will be reported and the methodological quality of studies will be assessed. When appropriate, we will provide pooled odds ratio with 95% confidence intervals of the effect estimates, study clinical heterogeneity using pre-defined sensitivity and subgroup analyses, and study statistical heterogeneity using the I2 test.

DISCUSSION

The results of this systematic review will provide an evidence base regarding the potential clinical effects of donor characteristics on transfusion recipients to better guide policy and clinical practice. The evidence gathered from this review will also identify strengths and weaknesses of published studies regarding donor characteristics and transfusion outcomes and will identify knowledge gaps to inform future research in this field of transfusion medicine.

TRIAL REGISTRATION

PROSPERO Registration Number: CRD42013006726.

Transfusion and risk of infection in Canada: Update 2012

Although multiple critical steps are taken to minimize the risk of infection from transfusion of blood or blood products in developed countries, this risk can never be entirely eliminated. In Canada, the risks of noninfectious transfusion reactions, such as transfusion-related acute lung injury and major allergic or anaphylactic reactions, are greater than that of infection. This updated practice point provides an overview of transfusion infection risks in Canada. Infectious agents, systemic conditions, donor and recipient factors, and collection and infusion techniques are considered. Suggestions are offered to improve both system and process, and to help practitioners who are discussing informed consent with patients and parents before administering blood or a blood product.