Evaluation of the confidential unit exclusion form: the Canadian Blood Services experience

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.

Demographics and serological profile of blood donors who opt for the confidential unit exclusion in a blood bank in Sao Paulo, Brazil

Blood transfusion is still an irreplaceable therapeutic modality, widely applied to medical care. Clinical interviews and laboratory testing for transfusion-transmitted infections (TTI) are routinely performed to prevent TTI among the recipients. However, there is still a residual risk of TTI, and some blood banks have adopted the confidential unit exclusion (CUE) as an additional safety strategy. In this study, we investigated the demographic characteristics and laboratory results of the screening of TTI among blood donors who opted for the CUE, compared to blood donors who did not opt for the CUE. In this study, we included 32,261 blood donations collected in a single blood bank in Sao Paulo, Brazil. A very small proportion of donors (0.25%) opted for the CUE. They were mainly single males and were more likely to have HBV, syphilis, and other positive results in the combined screening for TTI, in comparison with those who did not opt for the CUE. This difference was statistically significant in both the univariable and the multivariable analysis adjusted for age, gender , marital status and years of schooling. Our findings highlight that CUE may be a useful tool to improve the safety for blood recipients, but its efficiency is context-dependent.

Evaluation of the confidential unit exclusion on Iranian blood donors: An 11-year experience

BACKGROUND:

Confidential unit exclusion (CUE) was recommended by the Food and Drug Administration to permit blood donors confidentially exclude their donation for transfusion. However, its effectiveness as a safety measure to the blood supply is debated.

AIMS:

We, therefore, evaluated its benefit in identifying donors at risk of transmitting transfusion-transmissible infections (TTIs) and increasing blood safety in our population.

SETTINGS AND DESIGN:

This was a cross-sectional and retrospective study. The study was performed at the South Khorasan Blood Transfusion Center.

MATERIALS AND METHODS:

In this descriptive and retrospective study, data of CUE use and data of confirmed positive TTI markers were analyzed for the study period 2006–2016.

STATISTICAL ANALYSIS:

Data were analyzed using SPSS software version 16.

RESULTS:

Out of 165,267 donations, the CUE option was selected by 493 (0.3%) donors, most frequently by first-time blood donors, by men, by donors with <12 years schooling, and by 18–24-year-old donors. The data revealed that donations from CUE donors had no higher infection rates. Moreover, CUE showed low sensitivity (0.6%) and low positive predictive value (0.6%) in detecting TTI markers.

CONCLUSION:

The data do not provide any indication of a safety advantage from CUE; thus, we recommend that the procedure of CUE can be discontinued.

First-time Blood Donors Are Double-edged Swords for Blood Transfusion Centers: A Retrospective Study in Southwest Iran

Objective:

First-time blood donors are the most common group of blood donors. They usually have different motivations for blood donation, some of which provoke the donors to hide risk factors of transfusion-transmissible infections (TTIs). Therefore, detection of TTIs among first-time donors is crucial and can decrease the rate of TTIs among blood recipients. This study aimed to evaluate the prevalence of TTIs among first-time donors in the transfusion center of Kohgiluyeh and Boyer-Ahmad Province (KBTC), Iran.

Materials and Methods:

This retrospective study was conducted with volunteer blood donors in 2004-2014 in the KBTC. Various data, including sex, confidential unit exclusion (CUE), previous donation history, and the laboratory findings of confirmatory tests, were extracted from blood donor software. Data were analyzed by SPSS using the chi-square test.

Results:

Among 198,501 blood donors, 52,527 (26.46%) were first-time donors, while 145,974 donors (73.54%) were repeat and regular donors. Most of the donors (94.5%) were male, while a minority (5.5%) were female. The CUE option was chosen by 2,237 (1.13%) donors. The incidence of hepatitis B surface antigen (HBsAg) and hepatitis C virus (HCV) was 247 (0.13%) and 134 (0.07%) among the entire study population, respectively. Three donors (0.002%) had confirmed human immunodeficiency virus (HIV), while none of the blood donors were positive for syphilis. Most of the donors with positive HBsAg (95.8%), HCV (86.6%), and HIV (100%) infection were first-time donors.

Conclusion:

Since TTIs are more common among first-time blood donors than regular and repeat donors, special considerations should be taken into account for this common group of blood donors.

Confidential unit exclusion (CUE): Double edged sword for blood transfusion center: A ten-year study on volunteer blood donors in Kohgiluyeh and Boyer Ahmad province, Iran

BACKGROUND

Confidential unit exclusion (CUE) is a mechanism developed in the1980s to increase blood safety by allowing donors to indicate confidentially if they think their blood is not safe for transfusion. While it has been used widely around the world, the efficacy of this strategy is still unclear. The present study evaluated the efficacy of the CUE system at the Blood Transfusion Center of Kohgiluyeh and Boyer Ahmad Province (KBTC), Iran by comparing the prevalence of transfusion-transmitted infectious (TTIs) in CUE and non-CUE groups.

METHODS

This descriptive study used data from all volunteer blood donors over a ten-year period. Donors were classified in two groups: CUE and non-CUE. Screening tests were performed for hepatitis B surface antigens (HBs-Ag), hepatitis C virus antibody (HCV-Ab), and Human immunodeficiency virus antibody (HIV-Ab) and any repeatedly reactive results were confirmed by standard methods. Significant differences were determined by Chi² test. The sensitivity, specificity and PPV of the CUE system were also calculated.

RESULTS

In the present study, the non-CUE and CUE groups consisted of 98.94% and 1.06% of volunteer blood donors, respectively. First-time donors selected the CUE option more often than repeated and regular donors. The prevalence of TTIs was significantly higher in the CUE group and CUE sensitivity, specificity, and PPV were 5.5%, 98.95%, and 0.96%, respectively.

CONCLUSION

We recommend the CUE system be pursued for further enhancement of blood safety. However, further studies are needed to establish the overall usefulness of this procedure throughout the whole country.

High rate of seromarkers for HIV, HBV and syphilis among blood donors using confidential unit exclusion, before and after HIV-NAT implementation at a major public blood bank in the Brazilian Amazon

BACKGROUND

Confidential unit exclusion (CUE) was introduced in the 1980's as an additional layer to blood safety, before highly specific and sensitive nucleic acid tests (NAT) for HIV were implemented. The utility of CUE-use in settings that have implemented NAT should be evaluated over time.

STUDY DESIGN, METHODS

Cross-sectional retrospective study carried out from June 2010-November 2015, at Manaus Hemocenter (HEMOAM), Amazonas, Brazil that implemented HIV-NAT in 2012. The HIV, HCV, HBV, HTLV, Chagas disease, and syphilis rates were compared among CUE and non-CUE blood donors, before and after HIV-NAT implementation.

RESULTS

Among 287,588 donations, 2,154 (0.75%) were associated with CUE, mainly voluntary donations (64.2%), by repeat donors (58.4%) from young (median age = 31 years), males (84.4%), unmarried (63.1%). CUE-users compared to non-CUE donors (n = 285,434) had higher seropositivity rates to HIV (OR = 6.09, 95% CI: 3.68-10.07, p < 0.001), HBV (anti-HBc OR = 1.81 95% CI: 1.24-2.64, p = 0.004; HBsAg OR = 5.68, 95% CI: 1.78-18.07, p = 0.017), and syphilis (OR = 1.78, 95% CI: 1.05-3.04, p = 0.030). Most (97.2%) discarded blood units associated to CUE was seronegative for all pathogens. Most donations (73.4%) were tested by HIV-NAT and showed four window period donations, positive by HIV-NAT only among non-CUE donors.

CONCLUSION

A high rate of transfusion transmissible infections/TTIs was observed at HEMOAM especially in CUE-users. CUE-use offered an additional layer of blood safety by its association with anti-HBc/HBsAg and syphilis that are not covered by NAT. For blood banks in highly endemic areas for HIV and TTI, as HEMOAM, the identification of at risk donors, and the orientation to be tested at proper sites remain a great challenge.

Blood donors' awareness and attitudes towards blood transfusion safety in the Autonomous Province of Vojvodina, Serbia

OBJECTIVES

To assess the awareness and attitudes related to blood transfusion safety among blood donors from the Autonomous Province (AP) Vojvodina, Republic of Serbia.

BACKGROUND

Blood donors are at the initial point of safe blood transfusion systems. The active participation of blood donors in the selection process contributes to increasing the safety of blood transfusions and reduces potential risks for the recipients.

MATERIALS AND METHODS

This cross-sectional survey included 1191 blood donors from AP Vojvodina. The awareness and attitudes regarding safe blood supply were measured as 5-point scales of agreement/disagreement with statements on a Likert scale. The data were analysed using non-parametric methods by frequency modalities.

RESULTS

Male blood donors, the youngest age group (18-20 years), those who donate blood for the first time and those with a lower educational level showed the lowest awareness of, and the most negative attitudes about, blood safety.

CONCLUSIONS

The study found that there is a small but, for the safety of transfusion, significant number of blood donors who do not have a positive attitude or awareness of their own impact on safe transfusion therapy and who are not discovered during standard selection procedures.

A study on confidential unit exclusion at Shiraz Blood Transfusion Center, Iran

Background:

Confidential unit exclusion (CUE) system has been designed to enhance transfusion safety as an extra additive approach.

Aims:

This study was designed to survey demographic characteristics, prevalence of serologic markers, and reasons of opting CUE.

Materials and Methods:

The cross-sectional study was performed at Shiraz Blood Transfusion Center (Southern Iran). CUE is used for all individuals who refer for blood donation, and donors can choose their blood not to be used if they have any doubt about their blood suitability for transfusion. The prevalence rate of HIV, hepatitis B virus (HBV), and hepatitis C virus (HCV) was compared between the blood donors who opted into and out of CUE. Then, the donors were contacted to give another blood sample and the reasons of deferral. Researchers also determined whether their reasons were logical or not. Data were analyzed using comparison of proportions in MedCalc software 7.

Results:

Out of all the donors, 2365 ones (2.3%) opted for CUE. CUE was more frequent among men, singles, donors with low education levels, between 18 and 25 years old, and with history of previous donation (P < 0.05). The prevalence rate of HCV was higher among the donors who opted for CUE (P < 0.05), but it was not the case regarding HBV and HIV (P>0.05). Furthermore, 91.5% of the donors had opted for CUE by mistake and only 8% had chosen CUE logically.

Conclusion:

It is necessary to review the process of CUE, make some changes both in procedure and design, and then survey its effectiveness in blood safety.

Surveillance of transfusion-transmissible infections comparison of systems in five developed countries

Most industrialized countries maintain surveillance programs for monitoring transmissible infection in blood donations, revising approaches to methodology and risk assessment as new threats emerge. A comparison of programs in the United States, Canada, France, the UK, and Australia indicates that they have similar function, although the structure of blood programs vary as does the extent and nature of formal ties with public health. The emergence of HIV in the late 1970s and early 1980s was key in recognizing that surveillance systems specific to blood transfusion were essential. Hence, most industrialized countries monitor transfusion-transmissible infections in donors and evaluate the impact of new testing and of predonation screening strategies. Emerging infections since HIV have had different transmission pathways and challenged blood programs to draw upon resources for a rapid and effective response, with recognition that the original focus on sexual/drug-related risk of HIV and hepatitis was inadequate. The focus of surveillance programs on new and emerging pathogens fulfills a key role in risk assessment and policy formulation. The precise nature of such activities varies by country because of the structure of the blood programs and surveillance systems, the strategic focus of the blood programs, and the epidemiology of disease in each country.

Demographic characteristics and prevalence of serologic markers among blood donors who use confidential unit exclusion (CUE) in São Paulo, Brazil: implications for modification of CUE policies in Brazil

BACKGROUND

This study evaluated demographic profiles and prevalence of serologic markers among donors who used confidential unit exclusion (CUE) to assess the effectiveness of CUE and guide public policies regarding the use of CUE for enhancing safety versus jeopardizing the blood supply by dropping CUE.

STUDY DESIGN AND METHODS

We conducted a cross-sectional analysis of whole blood donations at a large public blood center in São Paulo from July 2007 through June 2009, compared demographic data, and confirmed serologic results among donors who used and who have never used CUE (CUE never).

RESULTS

There were 265,550 whole blood units collected from 181,418 donors from July 2007 through June 2009. A total of 9658 (3.6%) units were discarded, 2973 (1.1%) because CUE was used at the current donation (CUE now) and 6685 (2.5%) because CUE was used in the past (CUE past). The CUE rate was highest among donors with less than 8 years of education (odds ratio [OR], 2.78; 95% confidence interval [CI], 2.51-3.08). CUE now donations were associated with higher positive infectious disease marker rates than CUE never donations (OR, 1.41; CI, 1.13-1.77), whereas CUE past donations were not (OR, 1.04; CI, 0.75-1.45).

CONCLUSION

The CUE process results in a high rate of unit discard. CUE use on an individual donation appears predictive of a high-risk marker-positive donation and, thus, appears to contribute modestly to blood safety. The policy of discarding units from donors who have previously CUE-positive donations does not improve safety and should be discontinued.

Human immunodeficiency virus test-seeking blood donors in a large blood bank in São Paulo, Brazil

BACKGROUND

Persons with human immunodeficiency virus (HIV) risk behaviors are excluded from donation to reduce the risk of transfusion-transmitted infection. Persons donating to be tested for HIV may therefore deny risk behaviors.

STUDY DESIGN AND METHODS

A random sample of donors completed a survey on motivations, knowledge, and attitudes on the screening process. Donors were considered test seekers if they agreed with two statements "I think that blood donation is a good, fast, and anonymous way to get my blood tested" and "I donate to get my test results." This study was conducted from June to November 2006 at the largest blood bank in São Paulo, Brazil.

RESULTS

Of 3061 participants, 208 (7%) were test seekers. They tended to be male and had a lower educational level. They were more likely to have incorrect knowledge about blood safety (e.g., not knowing that a unit can test antibody negative and still transmit infection, 50% vs. 42%, p = 0.02), express dissatisfaction with screening questions (e.g., feeling that important questions were not asked, 14% vs. 5%, p < 0.01), and concur that donors do not answer questions truthfully (e.g., donors have more sexual partners than they admit, 29% vs. 18%, p < 0.01). Test seekers were more likely to believe that it is acceptable to donate blood to get tested for HIV (41% vs. 10%, p < 0.01).

CONCLUSIONS

Test-seeking motivation, coupled with low knowledge of window period risk, is counter to improving blood safety and to donor prevention needs. Donor education needs to be improved along with availability of appropriate HIV counseling and testing.