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A comprehensive seroepidemiologic study was conducted in two Red Cross regions (Los Angeles and Miami) to determine the prevalence of Trypanosoma cruzi antibodies in at-risk blood donors, to identify additional risk factors, and to assess the likelihood of transmitting T. cruzi by transfusion. At-risk and control donors were stratified by a broad risk question, tested for T. cruzi antibodies, and if confirmed as seropositive, enrolled in case-control and lookback investigations. A total of 299,398 donors were queried; 23,978 at-risk and 25,587 control donations were tested, and T. cruzi antibodies were confirmed in 34 donors (33 and 1, respectively). Seropositive donors shared one risk factor; birth/extensive time in a T. cruzi-endemic area. Lookback studies identified 11 recipients, all negative for T. cruzi antibodies. Screening strategies that use a question are unlikely to identify all seropositive donors. The lack of definitive data on the risk of transmission by transfusion indicates additional studies of donors and recipients are needed. [ABSTRACT FROM AUTHOR]

Background: ALT testing of blood donors was initiated as a surrogate marker for non-A, non-B hepatitis. Increased sensitivity of subsequent HBV and HCV tests used for standard donor screening make any residual value of ALT testing questionable., Study Design and Methods: A prospective study was conducted in 166 of 645 eligible blood donors from three American Red Cross regions whose ALT was > or =120 IU per L and whose standard donor screening tests were negative. Of these enrolled donors, 124 (75%) completed follow-up. Samples obtained from the index donation, at enrollment (1 month), and at follow-up (6 months) underwent the standard donor screening tests, as well as those for HCV RNA and HGV RNA (RT-PCR), antibodies to the virus envelope E2 protein of GB virus type C (GBV-C E2 antibody), and IgM antibody for CMV, parvovirus B19, EBV VCA, and HAV. Participants completed a brief demographic and exposure history questionnaire at follow-up., Results: All study samples were negative in standard donor-screening tests. ALT levels were variable at return visits, with 80 to 86 percent <120 IU per L. No participants were positive for HCV RNA; 4 percent were positive for HGV RNA, and 10 percent were positive for GBV-C E2 antibody. Results of CMV, parvovirus B19, EBV VCA, and HAV testing were similar to published background rates. No demographic or exposure history variables had significant correlation with ALT or other testing results., Conclusion: These data suggest that an ALT > or =120 IU per L in blood donors with negative standard screening tests has questionable value as a surrogate marker for seronegative HBV or HCV infection. Continued ALT testing may contribute little, if anything, to the safety of blood components or plasma for further manufacture.

Background: Severe, often fatal, transfusion reactions due to bacterial contamination of blood components continue to occur. Serratia liquefaciens, an unusual human pathogen, is a recently recognized potential cause of transfusion-related sepsis., Case Reports: Five episodes of transfusion-related sepsis and endotoxic shock due to S. liquefaciens were reported to the CDC from July 1992 through January 1999. One episode has been described. The remaining four, all fatal, are described here: three associated with RBC transfusion and one associated with transfusion of platelets. In each instance, the source of contamination could not be found. The implicated units tended to be older (mean RBC age 28 days), and visual discoloration was noted in each RBC unit, although usually in retrospect., Conclusion: S. liquefaciens is an increasingly recognized cause of transfusion-related sepsis and is associated with a high mortality rate. S. liquefaciens can contaminate both RBCs and platelets, but the mechanism(s) of contamination remain unknown. Increased attention to pretransfusion visual inspection may avert the transfusion of some S. liquefaciens-contaminated RBC units. However, more sensitive rapid diagnostic tests are needed to further reduce the risk of transfusion-related sepsis and endotoxic shock.

Background: This study evaluated the change from a rapid plasma reagin (RPR) test to an automated specific treponemal test (PK-TP) in screening for syphilis in blood donors., Study Design and Methods: A cross-sectional seroprevalence analysis was performed on 4,878,215 allogeneic blood donations from 19 American Red Cross Blood Services regions from May 1993 through September 1995. Positive predictive values relative to the confirmatory fluorescent treponemal antibody absorption test (FTA-ABS) were calculated. Differences in seroprevalence were compared in RPR and PK-TP tests for 1) unconfirmed and confirmed tests, 2) first-time and repeat donors, and 3) "recent" versus "past" infections. Donation data from three additional Red Cross regions were evaluated for repeat donation patterns of blood donors who had a donation that was positive in a serologic screening test for syphilis. The value of RPR and PK-TP tests as surrogate markers for HIV infection was compared., Results: Reactive rates were lower but the positive predictive values was higher for the PK-TP test than for the RPR test. Initially, donors screened by PK-TP were more likely to be confirmed as positive than were donors screened by RPR, but these rates became comparable. It is estimated that a single HIV window-period donation was removed by serologic testing for syphilis each year of this study period., Conclusions: The change to the PK-TP test resulted in a lower repeatedly reactive rate, better prediction that a confirmed-positive test for syphilis would occur in testing in the FTA-ABS, fewer donations lost, and comparable deferral rates. Because of the high rate of reactivity to serologic testing for syphilis among donors previously confirmed positive for syphilis, indefinite deferral after a confirmed-positive index donation may be warranted. Serologic testing for syphilis is ineffective as a marker of HIV-infectious window-period donations.

Knowledge of the epidemiologic pattern of human T-lymphotropic virus (HTLV) in the United States is being enlarged by blood donor screening. We tested stored sera from 29,937 donations made in South Florida in 1984-1985. Twenty-three donors were confirmed as seropositive, a prevalence of 0.8 per 1,000 donations. Specificity was supported by serologic retesting and virus culture of 11 donors located for follow-up. Sex- and age-specific prevalences did not differ significantly; blacks, however, accounted for 65% of seropositive donations. Within South Florida, one section of Miami had a prevalence of 4.5 per 1,000 donations, significantly above the 0.1 to 1.1 per 1,000 rates for other parts. An epidemiologic association with known HTLV-I endemic areas could account for most infections; all seven typed isolates were characterized as HTLV-I. Exposures, however, were diverse, sometimes multiple, and had no necessary relationship to personal lifestyle. This finding suggests that sources of infection were varied. Seropositive family members emphasize familial clustering of HTLV-I infection.

Background: The p24 antigen of human immunodeficiency virus type 1 (HIV-1) is sometimes detected before antibody (anti-HIV-1) is detectable in the serum of recently infected persons. This has led to the consideration of p24-antigen testing for routine screening of blood donors., Methods: To estimate how many HIV-infected seronegative donors would be identified if p24-antigen screening was introduced, we tested selected donations from a repository of 200,000 serum samples from voluntary donors that was established in late 1984 and early 1985. The 8597 serum samples selected for p24-antigen screening were chosen because their donors had demographic characteristics known to be associated with a high prevalence of seropositivity., Results: The prevalence of anti-HIV-1 antibodies in the 1984-1985 serum samples selected for p24-antigen screening was 1.54 percent--more than 100 times the 0.012 percent prevalence in present-day donations in the United States. The antigen was detected in 15 of 132 serum samples (11.4 percent) from donors who had already been confirmed as seropositive. No instance of confirmed positivity for p24 antigen was found among the 8465 seronegative serum samples., Conclusions: These data indicate that the yield of screening for p24 antigen in volunteer donors to identify HIV-1 carriers would be negligible. We therefore recommend against routine screening with currently available p24-antigen assays.

It is prudent to avoid blood transfusion whenever possible. Recent reports question the standards previously considered acceptable for blood transfusion. Acute hemorrhage followed by hypovolemia, tachycardia and orthostatic hypotension with dizziness are still considered acceptable criteria for automatic blood transfusion in most patients. We report two cases in which hypovolemia, tachycardia and orthostatic hypotension with dizziness were present. Transfusion was avoided. Hypovolemia, tachycardia and orthostatic hypotension with dizziness do not require transfusion in a few carefully selected and well-monitored patients.

To study whether the administration of recombinant human erythropoietin increases the amount of autologous blood that can be collected before surgery, we conducted a randomized, controlled trial of erythropoietin in 47 adults scheduled for elective orthopedic procedures. The patients received either erythropoietin (600 units per kilogram of body weight) or placebo intravenously twice a week for 21 days, during which time up to 6 units of blood was collected. Patients were excluded from donation when their hematocrit values were less than 34 percent. All patients received iron sulfate (325 mg orally three times daily). The mean number of units collected per patient (+/- SE) was 5.4 +/- 0.2 for the erythropoietin group and 4.1 +/- 0.2 for the placebo group. The mean red-cell volume donated by the patients who received erythropoietin was 41 percent greater than that donated by the patients who received placebo (961 vs. 683 ml, P less than 0.05). Only 1 of the 23 patients treated with erythropoietin was unable to donate greater than or equal to 4 units (4 percent) as compared with 7 of the 24 patients who received placebo (29 percent). No adverse effects were attributed to erythropoietin. We conclude that recombinant human erythropoietin increases the ability of patients about to undergo elective surgery to donate autologous blood.

In its clinical presentation, malignant histiocytosis may mimic infections or hematologic neoplasms, and pathologically it may be mistaken for Hodgkin's disease, histiocytic lymphoma, or viral lymphadenitis. The case histories of three patients in whom malignant histiocytosis clinically and pathologically simulated granulomatous diseases are reported. Erythrophagocytosis was not present in the initial bone marrow aspirates from two of the patients. One patient was considered to hve sarcoidosis or Wegener's granulomatosis; the second patient, Weber-Christian disease, and the third patient, a granulomatous disease of infectious origin. Granulomas have been found in tissues of patients who have Hodgkin's disease, but have been found only rarely in association with malignant histocytosis. An explanation for the presence of granulomas in association with malignant histiocytosis is offered: they may represent a phase in the evolution of the disease.

Since early 1985, blood donations in the United States have been screened for antibody to human immunodeficiency virus (HIV). To identify instances of HIV transmission by antibody-negative donations, we investigated 13 persons seropositive for HIV who had received blood from 7 donors who were screened as negative for HIV antibody at the time of donation. Twelve of the 13 recipients had no identifiable risk factors for HIV infection other than the transfusions they had received. On evaluation 8 to 20 months after transfusion, HIV-related illnesses had developed in three recipients, and the acquired immunodeficiency syndrome had developed in one. All seven donors were found to be infected with HIV. On interview, six reported a risk factor for HIV infection, and five had engaged in high-risk activities or had had an illness suggestive of acute retroviral syndrome within the four months preceding their HIV-seronegative donation. Thus, these donors had apparently been infected only recently, and so were negative at the time of blood donation according to available antibody tests. We conclude that there is a small but identifiable risk of HIV infection for recipients of screened blood. To minimize this risk, the reasons for deferral of donation need to be communicated more effectively to blood donors who are at high risk of HIV infection, and new assays that detect HIV infection earlier should be evaluated for their effectiveness in screening donated blood.