Male microchimerism in peripheral blood leukocytes from women with multiple sclerosis

BACKGROUND

Fetal microchimerism (F-MC), the persistence of fetal cells in the mother, is frequently encountered following pregnancy. The high prevalence of F-MC in autoimmune disease prompts consideration of the role for immune tolerance and regulation. This study examines the association between F-MC and multiple sclerosis (MS), an autoimmune disorder, of undetermined etiology.

RESULTS

21 out of 51 MS-positive subjects (41%) were classified as positive for F-MC; 4 of 22 (18%) of MS-negative sibling controls, were also positive for MC (p = 0.066). Unanticipated F-MC in controls lead to re-evaluation using 30 female singleton cord blood units (CBUs) as a biological control. Four CBUs were low-level positive.

STUDY DESIGN AND METHODS

Seventy-three female subjects were assigned to three groups according to disease status and pregnancy history: (1) MS positive (+) women with a history of one male pregnancy before symptom onset (n = 27); (2) MS negative (-) female siblings of MS(+) women with a history of one male pregnancy (n = 22); and (3) MS(+) women that reported never having been pregnant (n = 24). Ten micrograms of genomic DNA obtained from peripheral blood leukocytes of each subject were analyzed for F-MC using allele-specific real-time PCR targeting the SR-Y sequence on the Y-chromosome. MC classification was dichotomous (positive vs. negative) based on PCR results.

CONCLUSION

The association between F-MC and MS warrants further study to define this relationship. F-MC in women self-reporting as nulligravid, supports previous findings that a significant proportion of pregnancies go undetected. This lead to re-validation of a Y-chromosome based assay for F-MC detection.

Development of a web-based application and multicountry analysis framework for assessing interdicted infections and cost-utility of screening donated blood for HIV, HCV and HBV

BACKGROUND AND OBJECTIVES

Most countries test donations for HIV, HCV and HBV using serology with or without nucleic acid testing (NAT). Cost-utility analyses provide information on the relative value of different screening options. The aim of this project was to develop an open access risk assessment and cost-utility analysis web-tool for assessing HIV, HCV and HBV screening options (http://www.isbtweb.org/working-parties/transfusion-transmitted-infectious-diseases/). An analysis for six countries (Brazil, Ghana, the Netherlands, South Africa, Thailand and USA) was conducted.

MATERIALS AND METHODS

Four strategies; (1) antibody assays (Abs) for HIV and HCV + HBsAg, (2) antibody assays that include antigens for HIV and HCV (Combo) + HBsAg, (3) NAT in minipools of variable size (MP NAT) and (4) individual donation (ID) NAT can be evaluated using the tool. Country-specific data on donors, donation testing results, recipient outcomes and costs are entered using the online interface. Results obtained include the number infections interdicted using each screening options, and the (incremental and average) cost-utility of the options.

RESULTS

In each of the six countries evaluated, the use of antibody assays is cost effective or even cost saving. NAT has varying cost-utility depending on the setting, and where adopted, the incremental cost-utility exceeds any previously defined or proposed threshold in each country.

CONCLUSION

The web-tool allows an assessment of infectious units interdicted and value for money of different testing strategies. Regardless of gross national income (GNI) per capita, countries appear willing to dedicate healthcare resources to blood supply safety in excess of that for other sectors of health care.

Ribeiro AL, Cerdeira Sabino E. Mortality among blood donors seropositive and seronegative for Chagas disease (1996-2000) in São Paulo, Brazil: A death certificate linkage study

Background

Individuals in the indeterminate phase of Chagas disease are considered to have mortality rates similar to those of the overall population. This study compares mortality rates among blood donors seropositive for Chagas disease and negative controls in the city of São Paulo, Brazil.

Methodology/principal findings

This is a retrospective cohort study of blood donors from 1996 to 2000: 2842 seropositive and 5684 seronegative for Chagas disease. Death status was ascertained by performing probabilistic record linkage (RL) with the Brazil national mortality information system (SIM). RL was assessed in a previous validation study. Cox Regression was used to derive hazard ratios (HR), adjusting for confounders. RL identified 159 deaths among the 2842 seropositive blood donors (5.6%) and 103 deaths among the 5684 seronegative (1.8%). Out of the 159 deaths among seropositive donors, 26 had the 10th International Statistical Classification of Diseases and Related Health Problems (ICD-10) indicating Chagas disease as the underlying cause of death (B57.0/B57.5), 23 had ICD-10 codes (I42.0/I42.2/I47.0/I47.2/I49.0/I50.0/I50.1/ I50.9/I51.7) indicating cardiac abnormalities possibly related to Chagas disease listed as an underlying or associated cause of death, with the others having no mention of Chagas disease in part I of the death certificate. Donors seropositive for Chagas disease had a 2.3 times higher risk of death due to all causes (95% Confidence Interval (95% CI), 1.8–3.0) than seronegative donors. When considering deaths due to Chagas disease or those that had underlying causes of cardiac abnormalities related to Chagas disease, seropositive donors had a risk of death 17.9 (95% CI, 6.3–50.8) times greater than seronegative donors.

Conclusions/significance

There is an excess risk of death in donors seropositive blood for Chagas disease compared to seronegative donors. Chagas disease is an under-reported cause of death in the Brazilian mortality database.

Chagas disease is classified as one of the 17 most important neglected diseases by the World Health Organization (WHO). The majority of infected individuals live in 21 countries of Central and South America. Estimates of mortality attributable to Chagas disease vary considerably (between 0.2% and 19.2% annually). To improve the measurement of disease burden and policy decision-making in regard to treatment availability, more accurate estimates of mortality, especially among otherwise asymptomatic seropositive individuals are needed,. This study compares mortality rates and causes of death of asymptomatic blood donors who tested seropositive for Chagas disease and seronegative for all screening tests conducted in Brazil. Mortality status was ascertained by linking donor names with the Brazilian national mortality information system (SIM). The study found that donors who tested Chagas disease seropositive had risk of death from all causes 2.3 (95% CI, 1.8–3.0) times greater than seronegative ones. The data also suggest that the SIM may underestimate the total number of deaths attributable to Chagas disease in Brazil.

Correlation of West Nile Virus Incidence in Donated Blood with West Nile Neuroinvasive Disease Rates, United States, 2010-2012

Over the past decade, West Nile virus (WNV) has spread across the United States. We aggregated blood donor data from 2010–2012 and then calculated the incidence of WNV RNA–positive donations and compared the incidence with neuroinvasive disease (NID) case data from the ArboNET surveillance system. Of 10,107,853 donations, 640 were confirmed positive. The seasonal WNV incidence rate per 100,000 persons was 33.4 (95% CI 22–45) in 2010, 25.7 (95% CI 15–34) in 2011, and 119.9 (95% CI 98–141) in 2012. NID to blood donor ratios were 1 in 164 (95% CI 152–178) in 2010, 1 in 158 (95% CI 145–174) in 2011, and 1 in 131 (95% CI 127–136) in 2012. We updated estimates of the ratio of NID to WNV infection rates, demonstrating stable disease penetrance over the study period. Blood donor WNV RNA screening is a valuable public health tool for WNV surveillance.

A randomized trial to evaluate the use of text messaging, letter, and telephone call reminders to improve return of blood donors with reactive serologic tests

BACKGROUND

Low return rates for notification and counseling among donors with reactive serologic screening tests have been reported worldwide. A randomized trial to test the effectiveness of text message, letter, or telephone call reminders to improve return among nonresponding first-time blood donors with reactive serologic tests was conducted.

STUDY DESIGN AND METHODS

Donors with serologically reactive screening test results who had a cell phone and resided in the metropolitan telephone area code of São Paulo in the period from August 2013 through July 2014 were eligible. A consecutive sample of first-time donors with reactive screening tests who had not responded to a standard letter requesting the donor return to the blood center were randomly assigned to receive a text, a new letter, or a telephone call requesting return for notification and counseling. Return rates were measured over the subsequent 30 days.

RESULTS

The return rate after a phone call reminder was better than that for a text message (39.8% vs. 28.4%; odds ratio [OR], 1.66; 95% confidence interval [CI], 1.05-2.64) but not better than that for a letter (39.8% vs. 34.4%; OR, 1.26; 95% CI, 0.80-1.99). Older age was a predictor of higher rate of return with each year increase in age associated with a 2% increase in the odds of return (OR, 1.02; 95% CI, 1.01-1.04).

CONCLUSION

In nonresponding serologic reactive donors, telephone call led to a higher return rate than text message. The results of this study suggest that use of text messages, while attractive for its simplicity, will not lead to increased donor notification success after serologically reactive marker results from blood donation in Brazil.

Self-reported historic human immunodeficiency virus (HIV) testing in a Brazilian blood donor HIV case-control study

BACKGROUND

There has been increased worldwide emphasis on the many benefits of human immunodeficiency virus (HIV) serostatus awareness for both infection prevention and improved treatment outcomes. Previous studies indicate that donors may use blood donation to be tested; the objectives of this analysis were to assess, among donors with previously undisclosed risk behavior in the 12 months before donation, the frequency of those who have previously been tested for HIV and the demographic and behavioral factors associated with such testing.

STUDY DESIGN AND METHODS

In this secondary analysis from an HIV case-control study of blood donors in Brazil, we analyzed the response to the question, "Other than blood donation, have you ever been tested for HIV?" Demographic and disclosed risk behaviors associated with previous testing were determined.

RESULTS

The study included 341 HIV-positive cases and 791 HIV-negative controls (1:2 case/control ratio). Overall, 31% of blood donors (40% of cases and 26% of controls) reported having been tested for HIV outside of blood donation. History of HIV testing varied according to sex, HIV status, and reported sexual risk behavior.

CONCLUSION

Although it is encouraging that previous testing was more frequent in donors with acknowledged sexual risk behavior in Brazil, 60% still had not been tested for HIV outside of the blood donation setting. Educating donors on the importance of not using blood centers as a means to get tested for HIV in Brazil, especially if they engage in higher risk behaviors, and seeking alternate testing venues instead could improve the safety of donated blood.

Community Blood Supply Model: Development of a New Model to Assess the Safety, Sufficiency, and Cost of the Blood Supply

Background. Through a combination of predonation donor screening and donated unit testing, the blood supply is safer than ever. However, as a result of increasingly stringent screening measures, one of the greatest threats may be an insufficient supply. The balance between safety and adequacy of the blood supply has not received enough attention. Study Design and Methods. The authors developed a model to allow for empirical investigation of the determinants of a safe and sufficient supply. The model is a cohort simulation of allogeneic whole-blood donation, with the population of presenting donors stratified into 8 age and gender groups because the probability of donor and donation deferral varies by these characteristics. Parameters are estimated from year 2000 Blood Centers of Pacific (BCP) data. The model includes cost parameters, which were estimated using BCP expenditure data. The main outcomes are the number of transfusable units of blood and the unit cost of procurement. Results. The model tracks the production of a supply of blood, highlighting the influence of demographic characteristics, predonation deferral, underweight collection of blood units, and associated costs. The authors sought to establish model validity by showing that modeled results closely mimic the outcomes and costs observed by blood bank administrators. Conclusion. The model was developed to evaluate blood safety and policy decisions; it can be used to assess the impact of predonation deferrals, such as expanded European travel deferral for variant Creutzfeldt-Jakob disease, or the impact of new testing strategies, such as nucleic acid testing for West Nile virus.

Motivations for donating and attitudes toward screening policies in US blood donors with viral infection

BACKGROUND

Differences in motivating factors that contribute to the decision to donate blood between infected and uninfected donors may help to identify areas for improving donor education.

STUDY DESIGN AND METHODS

As part of a risk factor study, confirmed-positive donors (cases) based on serology-only (human T-lymphotropic virus [HTLV]) or serology and nucleic acid testing (NAT) or NAT-only (human immunodeficiency virus [HIV], hepatitis B virus [HBV], hepatitis C virus [HCV]), and serology-unconfirmed, NAT-negative false-positive donors (controls) were asked about motivations and opinions toward blood donation. "Test seeking" was inferred if a donor answered "yes" to "I wanted to get my test results" and one of the following: "blood center testing is confidential," "free," "more accurate than other test centers," or "tests will identify problems with my blood." Cases were compared to controls using descriptive and multivariable analyses.

RESULTS

Whether a case or control, the most common donation reason was "to help someone in need" (>90% in each group). After adjusting for demographic characteristics, test seeking was not significantly associated with infection status. Test seeking was more common in first-time, younger males and nonwhite, non-Hispanic donors. Of donors with HIV, 13% considered selection policies to be unfair, compared with 1, 2, 0.5, and 6% of donors with HBV, HCV, and HTLV and controls, respectively (adjusted odds ratio for HIV cases vs. controls, 3.9; 95% confidence interval, 2.3-6.7).

CONCLUSIONS

Most donors give to help those in need, including HIV-positive donors. Our results establish a baseline from which additional studies can be compared focused on alternate ways to reduce noncompliance and improved messaging to ensure that high-risk potential donors understand the reasons for blood donor screening policies.

Duration of Dengue Viremia in Blood Donors and Relationships Between Donor Viremia, Infection Incidence and Clinical Case Reports During a Large Epidemic

BACKGROUND

Dengue viruses (DENV-1-4) pose a transfusion-transmission risk. This study estimated the dengue RNA detection period in asymptomatic blood donors and relationships between donor viremia and dengue incidence during a large epidemic.

METHODS

Donor samples from the 2012 dengue transmission season in Rio de Janeiro, Brazil, were tested for DENV RNA by a transcription-mediated amplification (TMA) assay, with DENV types and viral loads determined by polymerase chain reaction. Samples collected during the first and last weeks of enrollment were tested for DENV immunoglobulin (Ig) G and IgM to estimate incidence during the study period, which was analyzed relative to nucleic acid amplification technology (NAT) yield to estimate the duration of NAT-detectable viremia and compared with reported clinical dengue cases in Rio.

RESULTS

Samples from 16 241 donations were tested; 87 (0.54%) were confirmed as DENV-4 RNA positive. Dengue IgM-positive/IgG-positive reactivity increased from 2.8% to 8.8%, indicating a 6.2% incidence (95% confidence interval [CI], 3.2%-9.1%) during the study period. Based on these data, we estimated a 9.1-day period (95% CI, 4.4-13.9 days) of RNA detectable with TMA. With 100 475 reported cases of clinical dengue, 1 RNA-positive donation was identified per 800 DENV cases.

CONCLUSIONS

These parameters allow projections of dengue incidence from donor NAT yield data and vice versa, and suggest that viremic donations will be rare relative to clinical disease cases.

Saving lives, maintaining safety, and science-based policy: qualitative interview findings from the Blood Donation Rules Opinion Study (Blood DROPS)

BACKGROUND

Indefinite deferral from donation for any man who discloses having had sex with another man even once since 1977 (MSM77) is the US FDA's standing policy. This qualitative component of the Blood Donation Rules and Opinion Study was designed to provide insight into the perceptions and practices of current or previous donors with MSM history.

STUDY DESIGN AND METHODS

Forty human immunodeficiency virus (HIV)-negative MSM completed an online survey, indicating that they had donated blood and were willing to be interviewed. Semistructured, individual interviews with these key informants covered donation experience and motivations, perceptions of MSM77, policy change preferences, and possible impact of a change to a time-limited deferral. Transcripts were coded deductively and inductively, following a modified Grounded Theory approach. Analysis identified recurrent and divergent themes.

RESULTS

Ninety-five percent of participants endorsed modifying MSM77. Preferred deferral length ranged from none to 5 years; a common opinion was that a science-based deferral period would be less than 1 year. Other policy change recommendations included incorporating questions about specific HIV risk behaviors to the donor questionnaire for all potential donors. Interviewees recognized HIV infection rates are higher in MSM than the general US population, but participants considered themselves low-risk for HIV, donated blood "to save lives," and justified their recommendations as being more effective ways to identify donors at risk for HIV.

CONCLUSION

Results suggest that MSM donors are concerned with blood safety; they can be appealed to as such. Communications about a new deferral policy should include scientific explanations and acknowledge altruistic motivations of potential donors.

Blood donor deferral for men who have sex with men: the Blood Donation Rules Opinion Study (Blood DROPS)

BACKGROUND

In the United States, any man who discloses having had sex with another man (MSM) even once since 1977 is currently deferred from donating blood. A study was conducted to assess noncompliance with the policy at four geographically dispersed blood centers.

STUDY DESIGN AND METHODS

Male donors 18+ years of age with e-mail addresses were randomly selected and invited to complete a confidential online survey between August and October 2013. No additional recruitment e-mails were sent. Survey content included demographics, sexual history, donation history, compliance with the policy, and opinions about current and modified policies.

RESULTS

Response rate was 11.5% but varied by center (6.3% to 21.7%). Of 3183 completed surveys, 2.6% of respondents (95% confidence interval, 2.1%-3.2%) reported donation after male-male sex. Noncompliance was not statistically different among the centers (p = 0.1), but was related to age with 5.7, 4.6, 2.5, and 1.0% of donors 18 to 24, 25 to 34, 35 to 54, and 50+ years of age, respectively, reporting noncompliance (p < 0.001). Of all respondents, 6.8% reported at least six female and 0.3% reported at least six male sex partners in the past 5 years. Opinions about the current MSM policy were mixed with noncomplying donors more supportive of change than complying donors. Approximatey half of noncompliers indicated they would adhere to a 1-year deferral.

CONCLUSION

Noncompliance with the MSM policy is evident and may be increasing compared to earlier data. Any change from the current policy will require close monitoring to determine whether it affects residual risk of HIV in the US blood supply.

Transfusion-Transmitted Dengue and Associated Clinical Symptoms During the 2012 Epidemic in Brazil

BACKGROUND

A linked donor-recipient study was conducted during epidemics in 2 cities in Brazil to investigate transfusion-transmitted (TT) dengue virus (DENV) by DENV RNA-positive donations.

METHODS

During February-June 2012, samples were collected from donors and recipients and retrospectively tested for DENV RNA by transcription-mediated amplification. Recipient chart review, using a case (DENV positive)-control (DENV negative and not known to be exposed) design, was conducted to assess symptoms.

RESULTS

Of 39 134 recruited blood donors, DENV-4 viremia was confirmed in 0.51% of donations from subjects in Rio de Janeiro and 0.80% of subjects in Recife. Overall, 42 DENV RNA-positive units were transfused into 35 recipients. Of these, 16 RNA-positive units transfused into 16 susceptible recipients were identified as informative: 5 cases were considered probable TT cases, 1 possible TT case, and 10 nontransmissions. The TT rate was 37.5% (95% confidence interval [CI], 15.2%-64.6%), significantly higher than the viremia rate of 0.93% (95% CI, .11%-3.34%) in nonexposed recipients (P < .0001). Chart review did not find significant differences between cases and controls in symptoms or mortality.

CONCLUSIONS

During a large epidemic of DENV-4 infection in Brazil, >0.5% of donations were RNA positive, and approximately one third of components resulted in TT. However, no significant clinical differences were evident between RNA-positive and RNA-negative recipients.

Bimodal distribution of Trypanosoma cruzi antibody levels in blood donors from a highly endemic area of Argentina: what is the significance of low-reactive samples?

BACKGROUND

Low-level seroreactive donor samples that are inconsistently detected by different Trypanosoma cruzi immunoassays are common, but the population distribution has not been reported in an endemic region. The objective was to understand the distribution of low-level reactive samples using highly sensitive immunoassays and the relationship with epidemiologic evidence of exposure to T. cruzi.

STUDY DESIGN AND METHODS

Blood donors (BDs) were recruited in two blood banks located in Chaco province, in northeastern Argentina, from June 2006 to March 2007. Donors completed a Chagas exposure questionnaire and provided blood samples. All samples were tested in parallel with five contemporary and commercially available enzyme immunoassays for T. cruzi and a subgroup by a chemiluminescent assay.

RESULTS

Of the 1423 enrolled donors, 304 (21.4%) tested positive on all assays while 93 (6.5%) were reactive on at least one assay (inconclusive). Epidemiologic evidence of exposure to T. cruzi was significantly higher among positive and inconclusive donors compared to seronegative BD (p values range from 0.01 to <0.001 depending on the exposure). Histograms of the signal-to-cutoff values from all positive samples showed clear bimodal distributions for the whole parasite lysate assays, but not for the one recombinant antigen-based assay. Low antibody level responses were present in 30% to 40% of the reactives, depending on the assay.

CONCLUSION

The population of individuals exposed to T. cruzi in highly endemic regions has a bimodal distribution of antibody response to the parasite. Although the clinical significance of low-level reactivity is not fully established, these results may reflect evolving seroreversions after spontaneously resolved infections.

Introducing Pathogen Reduction Technology in Poland: A Cost-Utility Analysis

BACKGROUND

Mirasol® pathogen reduction technology (PRT) uses UV light and riboflavin to chemically inactivate pathogens and white blood cells in blood components. In the EU, Mirasol PRT is CE-marked for both plasma and platelet treatment. In Poland, the decision to introduce PRT treatment of the national supply of fresh frozen plasma has spurred interest in evaluating the cost-effectiveness of this strategy.

METHODS

A decision-analytic model evaluated the incremental costs and benefits of introducing PRT to the existing blood safety protocols in Poland.

RESULTS

Addition of PRT treatment of plasma to current screening in Poland is estimated to cost 2.595 million PLN per quality-adjusted life year (QALY) (610,000 EUR/QALY); treating both plasma and platelet components in addition to current safety interventions had a lower cost of 1.480 million PLN/QALY (348,000 EUR/QALY).

CONCLUSIONS

The results suggest that in Poland the cost per QALY of PRT is high albeit lower than found in previous economic analyses of PRT and nucleic acid testing in North America. Treating both platelets and plasma components is more cost-effective than treating plasma alone. Wide confidence intervals indicate high uncertainty; to improve the precision of the health economic evaluation of PRT, additional hemovigilance data are needed.