ABSTRACT
BACKGROUND AND OBJECTIVES: Converting first-time donors to become regular donors continues to be a challenge facing blood centres. We examined whether first-time donors with frequent return in the first 12 months were more likely to become regular donors. SUBJECTS AND METHODS: The donation histories of 179 409 community whole-blood donors, whose first-time donation in 1991 was negative on donor screening tests, were evaluated. Donors were categorized by the number of donations made in the 12 months after (and including) their first donation. The donor return pattern in the subsequent 6 years, and its association with first-year donation frequency and demographics, was evaluated by using logistic regression analysis. A 'regular donor' was defined as one who returned to donate in at least 4 of the 6 years of follow-up. RESULTS: First-year donation frequency was significantly correlated with long-term donor return (P < 0.0001). Among those giving 1, 2, 3, 4 and > or = 5 donations in the first year, 4%, 11%, 21%, 32% and 42%, respectively, became regular donors (P < 0.0001). Similar associations between donation pattern and donor return behaviour were observed after adjusting for demographic variables (P < 0.0001). CONCLUSIONS: Strategies aimed at encouraging current donors to donate more frequently during the first year may help to establish a regular donation behaviour.
Subject(s)
Blood Donors/supply & distribution , Age Factors , Behavior , Blood Donors/psychology , Education , Humans , Regression Analysis , Sex FactorsABSTRACT
It has been reported that human T cell lymphotropic virus (HTLV)-I-infected persons in Japan have decreased delayed hypersensitivity skin test reactivity to tuberculin purified protein derivative (PPD), but HTLV-I- or -II-infected persons do not generally develop opportunistic infections. We administered standardized intradermal testing with PPD, mumps, and Candida albicans antigens to 31 HTLV-I, 48 HTLV-II, and 143 seronegative subjects in the United States. Reactivity at 48 hr was compared among the three groups. Response rates to PPD were very low in all subjects. Fifty-five percent of seronegative subjects did not react to mumps antigen, compared with 55% of HTLV-I [adjusted odds ratio (OR) = 0.79, 95% confidence interval (CI) 0.27-2.33] and 38% of HTLV-II (OR = 0.73, 95% CI 0.33-1.64). Fifty-one percent of seronegatives did not react to Candida albicans antigen, compared with 34% of HTLV-I (OR = 0.37, 95% CI 0.15-0.93) and 46% of HTLV-II (OR = 0.71, 95% CI 0.34-1.52). Anergy was present in 33% of seronegatives, 28% of HTLV-I (OR = 0.60, 95% CI 0.20-1.78), and 19% of HTLV-II (OR = 0.56, 95% CI 0.22-1.44). HTLV-I- and -II-infected persons appear to have intact delayed hypersensitivity skin test responses to mumps and Candida albicans antigens.
Subject(s)
Antigens, Fungal/immunology , Candida albicans/immunology , HTLV-I Infections/immunology , HTLV-II Infections/immunology , Hypersensitivity, Delayed/immunology , Mumps/immunology , Adult , Cohort Studies , Female , Humans , Hypersensitivity, Delayed/epidemiology , Male , Middle Aged , Racial Groups , Sex Factors , Skin Tests , Tuberculin/immunology , Tuberculin Test , United StatesABSTRACT
BACKGROUND: To evaluate whether the active recruitment of young donors of high school and college age could affect the safety of the blood supply, prevalence and incidence rates of infectious disease markers among donors aged 17 to 18 and 19 to 22 were compared to those in donors 23 years of age and older. STUDY DESIGN AND METHODS: Over 15 percent of 4.97 million whole blood donations were collected from donors aged 17 to 18 and 19 to 22. Prevalence (per 100,000 first-time donors) and incidence (per 100,000 person-years) rates for confirmed infectious diseases were compared between age groups. RESULTS: The prevalence estimates for HIV, HCV, HTLV-I and -II, and serologic tests for syphilis (STS) were significantly lower among first-time donors aged 17 to 18 and 19 to 22 than among those 23 to 44 years of age. HBsAg prevalence was higher in the first-time donors in the younger groups than in first-time donors in the older group because of higher prevalences among Asians and blacks. The incidence rates of HIV, HCV, and HTLV were similar in the younger groups and the older group. Donors 19 to 22 years of age had a higher incidence rate of estimated HBV than did donors aged 23 to 44 and 45+ (p<0.001), but the incidence rate of STS was lower in donors aged 17 to 18 and 19 to 22 than in donors 23 to 44 and 45+ years of age (p<0.001). CONCLUSION: Aggressive recruitment of school-age donors should not result in an increased risk of transmission-transmitted infections, with the possible exception of HBV.
Subject(s)
Biomarkers/blood , Blood Donors , Retroviridae Infections/transmission , Transfusion Reaction , Adolescent , Adult , Female , Humans , Incidence , Male , Middle Aged , Prevalence , Retroviridae Infections/blood , Retroviridae Infections/epidemiologyABSTRACT
Injection drug use (IDU) is a known risk factor for hepatitis C virus (HCV) infection, but the strength of other parenteral and sexual risk factors is unclear. In 1997, we performed a case-control study of 2,316 HCV-seropositive blood donors and 2,316 seronegative donors matched on age, sex, race/ethnicity, blood center, and first-time versus repeat-donor status. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated using conditional logistic regression. Questionnaires were returned by 758 (33%) HCV(+) and 1,039 (45%) control subjects (P =.001). The final multivariate model included only the following independent HCV risk factors: IDU (OR = 49.6; 95% CI: 20.3-121.1), blood transfusion in non-IDU (OR = 10.9; 95% CI: 6.5-18.2), sex with an IDU (OR = 6.3; 95% CI: 3.3-12.0), having been in jail more than 3 days (OR = 2.9; 95% CI: 1.3-6.6), religious scarification (OR = 2.8; 95% CI: 1.2-7. 0), having been stuck or cut with a bloody object (OR = 2.1; 95% CI: 1.1-4.1), pierced ears or body parts (OR = 2.0; 95% CI: 1.1-3.7), and immunoglobulin injection (OR = 1.6; 95% CI: 1.0-2.6). Although drug inhalation and a high number of lifetime sex partners were significantly more common among HCV seropositives, they were not associated with HCV after controlling for IDU and other risk factors. IDU, blood transfusion among non-IDU, and sex with an IDU are strong risk factors for HCV among United States blood donors. Weaker associations with incarceration, religious scarification, being stuck or cut with a bloody object, pierced ears or body parts, and immunoglobulin injection must be interpreted with caution.
Subject(s)
Blood Donors , Hepatitis C/transmission , Adult , Case-Control Studies , Female , Hepatitis C/epidemiology , Hepatitis C/immunology , Humans , Male , Middle Aged , Odds Ratio , Risk Factors , Seroepidemiologic Studies , Sexual Partners , Substance Abuse, Intravenous/complications , Surveys and Questionnaires , Transfusion Reaction , United States/epidemiologyABSTRACT
BACKGROUND: Efforts to provide a safe, adequate blood supply have been inhibited by persistent shortages attributed to a lack of motivation on the part of the general public and inefficiency in recruiting processes. This study examined whether frequency of donations and/or timing of subsequent donations by first-time donors related to donor demographics. STUDY DESIGN AND METHODS: Characteristics of 879,816 first-time donors making at least one whole-blood donation were analyzed. Cox proportional-hazards regression models evaluated the first 10 return times separately, and a recurrent-event Cox model was applied to simultaneously evaluate the first five returns. RESULTS: The shorter the donation interval between the first two donations, the more likely the donor was to make subsequent donations. The proportion of repeat donors increased with education level. Rate of donation increased with age and education. The recurrent-event Cox regression model showed that Rh-negative donors, older donors, and donors who had completed college had higher donation return rates. CONCLUSION: Time to return for second donation was associated with total number of donations made and with return rate for subsequent returns. Age was the strongest predictor of high donation frequency and early-return rate. Relationships between interdonation interval and the number of future donations may prove useful in understanding return behavior and developing donor recruitment and retention strategies.
Subject(s)
Behavior , Blood Donors/psychology , Adult , Aging/psychology , Blood Donors/education , Blood Donors/statistics & numerical data , Female , Humans , Male , Middle Aged , Proportional Hazards Models , Rh-Hr Blood-Group System/blood , Time FactorsABSTRACT
BACKGROUND: To determine whether human T-lymphotropic virus type II (HTLV-II) infection is associated with an increased incidence of bacterial infections, we prospectively observed cohorts of HTLV-I- and HTLV-II-infected and seronegative subjects in 5 US cities. METHODS: Of 1340 present and former blood donors examined at enrollment, 1213 (90.5%) were re-examined after approximately 2 years, including 136 HTLV-I- and 337 HTLV-II-seropositive subjects and 740 demographically stratified HTLV-seronegative subjects. All subjects were seronegative for human immunodeficiency virus. Odds ratios (ORs) for incident disease outcomes were adjusted for covariates, including age, sex, race or ethnicity, education, and, if significantly associated with the outcome, blood center, donation type, income, smoking, alcohol intake, and injected drug use. RESULTS: Compared with seronegative status, HTLV-II infection was associated with an increased incidence of bronchitis (OR, 1.81; 95% confidence interval [CI], 1.20-2.75), bladder and/or kidney infection (OR, 1.94; 95% CI, 1.26-2.98), oral herpes infection (OR, 9.54; 95% CI, 3.33-27.32), and a borderline increased incidence of pneumonia (OR, 2.09; 95% CI, 0.92-4.76); HTLV-I infection was associated with an increased incidence of bladder and/or kidney infection (OR, 2.79; 95% CI, 1.63-4.79). One incident case of HTLV-I-positive adult T-cell leukemia was observed (incidence, 348 per 100,000 HTLV-I person-years), and 1 case of HTLV-II-positive tropical spastic paraparesis-HTLV-associated myelopathy was diagnosed (incidence, 140 per 100,000 HTLV-II person-years). CONCLUSIONS: These data support an increased incidence of infectious diseases among otherwise healthy HTLV-II- and HTLV-I-infected subjects. They are also consistent with the lymphoproliferative effects of HTLV-I, and with neuropathic effects of HTLV-I and HTLV-II.
Subject(s)
Communicable Diseases/complications , Communicable Diseases/epidemiology , HTLV-I Infections/complications , HTLV-II Infections/complications , Adolescent , Adult , Child , Child, Preschool , Chronic Disease , Female , Follow-Up Studies , HTLV-I Infections/epidemiology , HTLV-I Infections/etiology , HTLV-II Infections/etiology , Humans , Incidence , Infant , Logistic Models , Male , Middle Aged , Neoplasms/complications , Neoplasms/epidemiology , Odds Ratio , Prospective Studies , Risk Factors , United States/epidemiologyABSTRACT
CONTEXT: Persons at risk of human immunodeficiency virus 1 (HIV-1) infection, have been classified incorrectly as HIV infected because of Western blot results, but the frequency of false-positive Western blot results is unknown. OBJECTIVES: To determine the frequency of false-positive HIV-1 Western blot results in US blood donors and to make projections to other screened populations. Secondarily, to validate an algorithm for evaluating possible false-positive cases. DESIGN: A retrospective cohort study of HIV-1 enzyme immunoassay (EIA) and Western blot results from large blood donor screening programs in which donors with suspected false-positive Western blot results underwent HIV-1 RNA polymerase chain reaction (PCR) testing and follow-up HIV-1 serology. SETTING: Five US blood centers participating in the Retrovirus Epidemiology Donor Study. PARTICIPANTS: More than 5 million allogeneic and autologous blood donors who successfully donated blood at 1 of the 5 participating centers from 1991 through 1995. MAIN OUTCOME MEASURES: Rate of false positivity by Western blot and true HIV-1 infection status as determined by HIV-1 RNA PCR and by serologic follow-up of blood donors more than 5 weeks after donation. RESULTS: Of 421 donors who were positive for HIV-1 by Western blot, 39 (9.3%) met the criteria of possible false positivity because they lacked reactivity to p31. Of these, 20 (51.3%) were proven by PCR not to be infected with HIV-1. The false-positive prevalence was 4.8% of Western blot-positive donors and 0.0004% (1 in 251000) of all donors (95% confidence interval, 1 in 173000 to 1 in 379000 donors). CONCLUSIONS: A false diagnosis of HIV-1 infection can result from the combination of EIA and Western blot testing in blood donor and other HIV-1 screening programs. Individuals with a positive Western blot result lacking the p31 band should be counseled that, although they may be HIV infected, there is uncertainty about this conclusion. These individuals should be further evaluated by RNA PCR testing (if feasible) and HIV serologic analysis on a follow-up sample.
Subject(s)
AIDS Serodiagnosis/classification , Blood Banks , Blood Donors/classification , Blotting, Western , HIV-1/isolation & purification , Algorithms , Counseling , False Positive Reactions , HIV Antigens , HIV Infections/classification , HIV Infections/diagnosis , HIV Seropositivity , Humans , Immunoenzyme Techniques , Polymerase Chain Reaction , RNA, Viral/analysis , Retrospective Studies , United StatesABSTRACT
BACKGROUND: The demographics, deferrable risk behaviors, and the prevalence and incidence of viral infections of apheresis (PH) and whole-blood (WB) donors were compared, to characterize these two populations and to evaluate the relative safety of PH and WB donors in terms of transfusion-transmitted viral infections. STUDY DESIGN AND METHODS: A comparison was made of 36,119 PH donors (> or = 1 PH donation) and 1.38 million WB donors (> or = 1 WB donation) in terms of demographics and the prevalence (/100,000 donors) and incidence (/100,000 person-years) of viral infections, by using data collected at five United States blood collection centers between 1991 and 1994. Deferrable risk behaviors were defined as those risk behaviors that would have resulted in donor deferral, had they been reported. The prevalence of deferrable risk behaviors was estimated by using data collected through an anonymous mail survey. RESULTS: PH donors were older and more likely than repeat (2+ donations) WB donors to be female, white, and United States-born and to have a higher degree of education (p < or = 0.001). The prevalence of any viral infection was 50 percent higher in WB donors than in PH donors (p = 0.04), whereas the incidence of HIV, human T-lymphotropic virus, and hepatitis B surface antigen was nonsignificantly higher in WB donors. The prevalence of deferrable risk behaviors did not differ in the two groups. CONCLUSION: Further studies will be needed to evaluate whether the difference in the prevalence of viral infections observed in this study can be explained by demographic characteristics and patterns of donation frequency.
Subject(s)
Demography , Risk-Taking , Virus Diseases/epidemiology , Blood Component Removal , Blood Donors , Female , Humans , Incidence , Male , PrevalenceABSTRACT
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. "Safe" donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of "safe" donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of "safe" donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among "safe" donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors.
Subject(s)
Blood Donors/psychology , Safety , Adult , Data Collection , Demography , Female , Humans , Male , Middle Aged , Patient Selection , Risk-Taking , VolunteersABSTRACT
BACKGROUND: Calculations of the incidence of hepatitis B virus (HBV) infections in the blood donor setting that are based solely on data for seroconversion to hepatitis B surface antigen (HBsAg) will underestimate the incidence due to the transient nature of antigenemia. Estimates based on antibody to hepatitis B core antigen will overestimate the incidence due to false-positive results caused by the nonspecificity of the test. STUDY DESIGN AND METHODS: Serologic test results were obtained from multiple-time volunteer donors at five United States blood centers from January 1991 through December 1993. The observed HBsAg seroconversion rate was multiplied by an adjustment factor, derived from the weighted average probability of a positive HBsAg test for HBV-infected donors who become chronic carriers, for donors with a primary antibody response without detectable antigenemia, and for donors who develop transient antigenemia. RESULTS: Among 586,507 multiple-time donors giving 2,318,356 donations and observed for 822,426 person-years, the HBsAg incidence rate was 4.01 per 100,000 person-years. On the basis of prior reports of the duration of HBsAg positivity and the observed distribution of interdonation intervals among the study group, there was an estimated 53-percent chance that an HBV-infected donor with transient antigenemia would have a positive HBsAg test result. If 70 percent of newly HBV-infected adults have transient antigenemia, 25 percent have a primary antibody response without primary antigenemia, and 5 percent become chronic carriers, the overall chance of being detected by the HBsAg test was 42 percent, for an adjustment factor of 2.38. The total HBV incidence rate, therefore, was estimated to be 9.54 per 100,000 person-years. CONCLUSION: The crude HBV incidence rate observed from HBsAg test results will underestimate the true rate. The adjusted HBV incidence rate should be used in applications such as estimations of residual HBV risk to the blood supply and projections of the benefits of screening for HBV DNA.
Subject(s)
Blood Donors , Hepatitis B/epidemiology , Adult , Blood Donors/statistics & numerical data , DNA, Viral/blood , Hepatitis B/immunology , Hepatitis B Surface Antigens/blood , Humans , Incidence , MethodsABSTRACT
BACKGROUND: Blood donors who test repeatably reactive on enzyme immunoassay (EIA) and are not confirmed as positive are a continuing problem for blood banks. Units are discarded and donors are deferred, in spite of multiple studies indicating that such donors are very rarely infected with the transmissible agents. Few data are available, however, with which to evaluate whether the discarded units are more likely to come from particular demographic subgroups. STUDY DESIGN AND METHODS: The Retrovirus Epidemiology Donor Study database of over 2 million allogeneic whole-blood donations collected in the years 1991 through 1993 was utilized. The prevalence of false-positive and indeterminate test results within demographic subgroups was computed for antibodies to human immunodeficiency virus, hepatitis C virus, and human T-lymphotropic virus (anti-HIV, anti-HCV, anti-HTLV, respectively) and hepatitis B surface antigen (false-positive only) as the proportion of donations that were repeatably reactive on EIA but negative or indeterminate on the confirmatory or supplemental test. RESULTS: Several demographic groups with increased prevalence of false-positive and indeterminate anti-HIV results were the same females, younger age groups, blacks, and first-time donors. Likewise, many of the demographic subgroups with increased prevalence of false-positive and indeterminate anti-HCV results were similar: older age groups, non-whites, lower education levels, first-time donors, donors making directed donations, and donors who had received transfusions. For anti-HTLV, by contrast, the oldest group had the highest prevalence of false-positive results but the lowest prevalence of indeterminate results: blacks had the lowest prevalence of false positive results but the highest prevalence of indeterminate results. CONCLUSION: If units that test repeatably reactive on EIA but that are not confirmed as positive are almost always from individuals not infected with the virus in question, then these results indicate that there may be sex-, race-, and/or age-linked proteins cross-reacting with the test kit materials. Elucidation of these antigenic determinates and their subsequent removal should be a priority.
Subject(s)
Blood Donors , Immunoenzyme Techniques , False Positive Reactions , HIV Seroprevalence , Hepatitis Antibodies/blood , Humans , Immunoenzyme Techniques/standards , Sensitivity and SpecificityABSTRACT
BACKGROUND: Latex allergy has been recognized as a medical problem with increasing frequency since the mid 1980s. Although certain groups of individuals, such as health care workers, have been recognized as having increased risk for latex allergy, little is known about the prevalence of latex allergy in the general population. METHODS: To estimate the prevalence of latex allergy among healthy adults, we measured anti-latex IgE antibodies in residual serum samples from 1000 volunteer Red Cross blood donors. The 1000 samples were from a sample of blood units collected from workplace mobile sites throughout Southeastern Michigan. Samples collected from mobile sites operating at health care institutions were excluded to minimize sampling of health care workers. Anti-latex IgE antibodies were measured by using the AlaSTAT assay (Diagnostic Products Corp., Los Angeles, Calif.) according to the manufacturer's directions. Samples with anti-latex IgE concentrations of 0.35 IU/ml or greater were classified as positive and samples with IgE concentrations of 1.50 IU/ml or greater were classified as strongly positive. All positive samples were assayed a second time to confirm the result. All positive samples were also measured with the CAP assay (Pharmacia Diagnostics, Dublin, Ohio). RESULTS: The samples tested were from donors with a mean age of 37.8 years, and 47% were women. Sixty-four (6.4%, 95% confidence interval = 4.9-8.1%) of the samples were confirmed as repeatedly positive for anti-latex IgE, and 23 of the 64 positive samples were strongly positive (2.3% of the 1000). Sixty-one percent of the samples positive as determined by the AlaSTAT assay were also positive as determined by the CAP assay. Samples from male donors were more likely to be positive than those from female donors (8.7% vs 4.1%, p = 0.003). Prevalence of positive samples was not related to age or race. CONCLUSIONS: We conclude that the prevalence of detectable anti-latex IgE antibodies, in a large and relatively unselected adult population, is higher than previous estimates have suggested. Although the clinical significance of these observations needs further evaluation, the data suggest that latex allergy is not confined to individuals in previously recognized high-risk groups.
Subject(s)
Blood Donors , Immunoglobulin E/immunology , Latex/immunology , Adolescent , Adult , Aged , Female , Humans , Male , Middle AgedABSTRACT
OBJECTIVE: To measure demographic determinants of hepatitis C virus (HCV) seroprevalence among blood donors in the United States. DESIGN: Cross-sectional epidemiological study. SETTING: Five blood centers in different regions of the United States. SUBJECTS: A total of 862,398 consecutive volunteer blood donors with one or more nonautologous donations from March 1992 through December 1993. METHODS: Demographic data collection, serological screening with second-generation anti-HCV enzyme immunoassay, and confirmation with anti-HCV recombinant immunoblot. RESULTS: There were 3126 donors with at least one blood donation confirmed HCV-seropositive, for a crude prevalence of 3.6 per 1000. Age-specific HCV seroprevalence rose from 0.5 per 1000 donors younger than 20 years to a maximum of 6.9 per 1000 in donors aged 30 to 39 years and declined in older age groups. There was interaction between age and educational attainment, with 30- to 49-year-olds with less than a high school diploma at highest risk of HCV infection (odds ratio [OR], 33.0; 95% confidence interval [CI], 23.0 to 47.2 compared with those younger than 30 years with a bachelor's degree or higher degree). Other independent risk factors for HCV seropositivity included male sex (OR, 1.9; 95% CI, 1.8 to 2.1), black race (OR, 1.7; 95% CI, 1.6 to 1.9), Hispanic ethnicity (OR, 1.3; 95% CI, 1.1 to 1.5), previous blood transfusion (OR, 2.8; 95% CI, 2.5 to 3.1), and first/only time donor status (OR, 4.2; 95% CI, 3.9 to 4.5 compared with repeat donors). Seropositivity for human T-lymphotropic virus types I and II, human immunodeficiency virus, or hepatitis B core antigen was highly associated with HCV seropositivity (OR, 10.4; 95% CI, 9.6 to 11.4 for one vs no marker). CONCLUSIONS: Despite a low overall HCV prevalence in blood donors in the United States, there is a marked variation in HCV seroprevalence by demographic subgroup, even after controlling for prior blood transfusion, a recognized risk factor for HCV. Further study of the prevalence of other parenteral risk factors such as past injection drug use among blood donors is needed.
Subject(s)
Blood Donors/statistics & numerical data , Hepatitis C/epidemiology , Adult , Age Distribution , Cross-Sectional Studies , Demography , Educational Status , Female , Hepacivirus/immunology , Humans , Male , Middle Aged , Prevalence , Risk Factors , Seroepidemiologic Studies , Socioeconomic Factors , United States/epidemiologyABSTRACT
BACKGROUND: The value of the test for antibody to hepatitis B core antigen (anti-HBc) as a surrogate screening assay in the time before sensitive, virus-specific screening tests were available has been well established. There is significant debate, however about the residual value of anti-HBc screening after the implementation of human immunodeficiency virus (HIV)-, human T-lymphotrophic virus (HTLV)-, and hepatitis C virus (HCV)-specific assays and, in particular, about its utility as a lifestyle marker to identify persons at risk for retrovirus infections. STUDY DESIGN AND METHODS: Screening tests for antibodies to HIV, HTLV, and HBc, as well as confirmatory or supplemental test results for anti-HIV and anti-HTLV, were obtained from approximately 2.8 million donations collected from 1991 through 1993 by five blood centers within the United States. The sensitivity, positive predictive value, and relative prevalence of anti-HBc for each retrovirus were calculated and compared among demographic subgroups. RESULTS: The overall relationship between anti-HBc and anti-HIV was similar to that between anti-HBc and anti-HTLV. When calculated from the measured endpoint of the prevalence of anti-HIV-positive and anti-HTLV-positive donations, the sensitivities were 31.1 and 26.2 percent, the positive predictive values were 0.18 and 0.21 percent, and the relative prevalences were 30.1 and 23.8, respectively. Among 27 anti-HIV-seroconverting donors and 9 anti-HTLV-seroconverting donors, the sensitivities were 7.4 percent (95% CI: 0.9-24.3%) and 0 percent (95% CI: 0.0-28.3%), respectively. It was estimated that for each HIV-infected window-period donation detected by anti-HBc, from 19,000 to 81,000 HIV-noninfected donations are discarded. Similarly, more than 33,000 HTLV-noninfected donations are likely to be discarded for each HTLV-infected donation detected by anti-HBc. CONCLUSION: Although anti-HBc-reactive donations are more likely to be seropositive for a retrovirus than are anti-HBc-nonreactive donations, the low positive predictive value limits the test's effectiveness. If the anti-HBc test is retained in the blood donor setting, efforts should be focused on reducing the number of false-positive results.
Subject(s)
Blood Donors , Deltaretrovirus Infections/diagnosis , HIV Infections/diagnosis , Hepatitis B Antibodies/blood , Hepatitis B Core Antigens/immunology , Adolescent , Adult , Female , HIV Seronegativity , HIV Seropositivity , Humans , Male , Middle Aged , Sensitivity and SpecificityABSTRACT
BACKGROUND: Follow-up studies from the mid-1980s showed that 1 to 5 percent of blood donors testing reactive in anti-human immunodeficiency virus type 1 (HIV-1) enzyme immunoassay (EIA) and testing indeterminate in Western blot were infected with HIV-1 and were in the process of seroconverting. The present study was conducted to establish the rate of HIV infection among contemporary anti-HIV-1/HIV type 2 (HIV-2) EIA-reactive, Western blot-indeterminate donors. STUDY DESIGN AND METHODS: Donations (n = 607) with indeterminate HIV supplemental test results were identified by screening 3,021,342 donations given from November 1990 through August 1993 at five participating blood centers. Consenting donors were enrolled and samples taken 4 to 8 weeks after donation. Follow-up sera were tested by EIA and Western blot for anti-HIV-1 seroconversion and by type-specific peptide assays for antibodies to HIV-2 and HIV-1 subtype O. Peripheral blood mononuclear cells and/or plasma from the follow-up samples were tested for HIV-1 DNA and/or RNA by polymerase chain reaction. The rate of HIV-1 infection among Western blot-indeterminate donors was also estimated by multiplying the incidence rate of HIV-1 seroconversion in this donor population by the estimated duration of the EIA-reactive and Western blot-indeterminate window during seroconversion (8.5 days). RESULTS: Supplemental test-indeterminate donors (n = 355) enrolled a median of 38 days after donation; 265 (75%) of these donors were identified as indeterminate after an anti-HIV-1/2 EIA-reactive donation. Enrolled and non-enrolled donors had similar distributions of demographic characteristics and band patterns. Follow-up samples from all 355 donors tested negative for HIV-1 in polymerase chain reaction. Follow-up sera tested Western blot-negative in 54 cases (15%) and Western blot-indeterminate in 299 (84%). Two follow-up sera (0.6%) were interpreted, according to manufacturer's package insert criteria, as Western blot positive with p24 and gp41 bands and/or gp120/160 bands; however, paired testing of index and follow-up sera from these two cases showed identical Western blot and EIA reactivity, and polymerase chain reaction was negative for HIV RNA and DNA, which ruled out HIV infection. The absence of HIV infection in 355 Western blot-indeterminate donors was consistent with our incidence-based model analysis, which yielded an estimate of one HIV-1 infection for every 215 Western blot-indeterminate donations (95% CI, 1/39-1/8333). CONCLUSION: Contemporary blood donors classified as indeterminate in supplemental HIV testing are infrequently infected with HIV. Donors whose follow-up samples test negative in anti-HIV-1/2 EIAs and negative or persistently indeterminate in Western blots should be considered eligible for reinstatement.
Subject(s)
Blood Donors , HIV Infections/diagnosis , HIV Seropositivity/diagnosis , Adult , Blotting, Western , DNA, Viral/analysis , Female , Follow-Up Studies , HIV-1/immunology , HIV-2/immunology , Humans , Immunoenzyme Techniques , Male , Middle Aged , RNA, Viral/analysis , Time FactorsABSTRACT
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a "random process," as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.
Subject(s)
Blood Donors , Blood Transfusion/psychology , Confidentiality , Disease Transmission, Infectious/prevention & control , Retroviridae Infections/transmission , Adolescent , Adult , Female , Humans , Male , Middle Aged , Prevalence , Retroviridae Infections/epidemiology , Sensitivity and SpecificityABSTRACT
Patients undergoing irradiation treatment for head and neck cancer need not lose their teeth. Careful treatment planning improves patients' quality of life.
Subject(s)
Dental Care for Disabled , Head and Neck Neoplasms/radiotherapy , Humans , Radiotherapy/adverse effectsABSTRACT
A total of 559 women with primary breast cancer treated by modified radical mastectomy were followed for a mean of 74.8 months to evaluate the relationship of sex hormone receptor content in the tumor with time to first recurrence and to death due to breast cancer. The prognostic significance of progesterone receptor (PgR) status was evaluated in terms of estrogen receptor (ER) status, age (less than or equal to 49 years, greater than or equal to 50 years), extent of lymph node involvement, tumor size, and morphologic characteristics. Overall, patients with PgR positive (greater than 9 femtomoles/10 mg wet weight tissue) tumors experienced a significantly longer period to both first recurrence and death due to breast cancer, but this advantage was restricted to those whose cancer had metastasized to their axillary lymph nodes. For women with nodal involvement, the extent of this involvement and the size of the primary lesion had the greatest predictive value followed by nuclear grade and PgR status. In these node-positive patients, PgR positivity, although strongly associated with ER positivity, had a greater predictive value than that of the estrogen receptor per se.
Subject(s)
Breast Neoplasms/diagnosis , Carcinoma/diagnosis , Receptors, Progesterone/analysis , Breast Neoplasms/mortality , Breast Neoplasms/surgery , Carcinoma/mortality , Carcinoma/surgery , Evaluation Studies as Topic , Female , Follow-Up Studies , Humans , Mastectomy, Modified Radical , Middle Aged , Neoplasm Recurrence, Local , Predictive Value of Tests , PrognosisABSTRACT
The present study attempts to identify poor prognosis subgroups of women with node-negative breast cancer that might benefit from systemic adjuvant therapy. The cases were collected through a cooperative effort of 57 surgeons at eight hospitals in the Detroit area and coordinated by the Michigan Cancer Foundation where data collection and analyses were completed. The primary treatment of all patients was a modified radical mastectomy. Of the 1,078 cases accessioned between October 1975 and April 1983, 537 were found to have no microscopic lymph node involvement and 462 of these cases received no adjuvant antineoplastic therapy. The period of follow-up of these cases (alive, n = 358) has been 78.75 +/- 24.6 months (mean +/- SD). Overall, the cumulative 6-year recurrence rate as calculated by life table analysis was 26%, with 16.8% dying of their disease. Tumor size was an important prognostic factor; the recurrence rate was 16.2% for those with primaries measuring less than or equal to 1 cm, with only a 6.3% mortality. Patients with tumors measuring greater than 5 cm also did well: 13.7% recurrence and 13.7% mortality rates at 6 years. The premenopausal women did slightly, but not statistically significantly, better than those who were postmenopausal. The presence or absence of quantifiable estrogen receptor protein (ER) was of little predictive value as far as rates of recurrence were concerned, but patients with an ER-positive tumor survived significantly longer. In postmenopausal women, those whose tumor lacked ER (n = 112) fared poorly: 30.4% experienced a recurrence by 6 years and 28% died of their disease. Recurrence rates and death rates were also high in a small group (n = 35) of postmenopausal women with ER+ tumors exhibiting nuclear pleomorphism (nuclear grade [NG]3) (38% and 24.3%, respectively). No poor prognosis group of premenopausal women was identified.