Severity of iron overload in hemochromatosis: effect of volunteer blood donation before diagnosis

BACKGROUND: An effort was made to determine if volunteer blood donation before diagnosis decreases the severity of iron overload at diagnosis in persons with hemochromatosis. STUDY DESIGN AND METHODS: A study was performed in 1089 persons in the United States with hemochromatosis who responded to a convenience sample survey and in 124 C282Y/C282Y hemochromatosis probands diagnosed during routine medical care. RESULTS: Less than half of questionnaire respondents (46.2%) and probands (35.5%) reported that they had been volunteer blood donors; 5.4 percent and 4.0 percent, respectively, had donated >20 units of blood. In either subject group, there were no significant differences according to age in the mean numbers of units that needed to be removed by therapeutic phlebotomy to induce iron depletion in subgroups of men and women, respectively. Similarly, there was no significant correlation of units of voluntary blood donation or of therapeutic phlebotomy index (= therapeutic phlebotomy units/age in years) with the number of therapeutic phlebotomy units needed to induce iron depletion. When questionnaire respondents were stratified by sex, there was no significant correlation of units of blood donation with the number of therapeutic phlebotomy units needed to induce iron depletion or with the therapeutic phlebotomy index. CONCLUSION: Routine blood donation does not, on average, decrease the severity of iron overload in persons with hemochromatosis. These findings have implications for the understanding of the severity of iron overload and its complications in hemochromatosis, for advising persons with hemochromatosis about treatment, and for considering persons with hemochromatosis as possible blood donors.     

Hemochromatosis subjects as allogeneic blood donors: a prospective study

BACKGROUND: Persons with hemochromatosis constitute a plentiful and willing source of blood for transfusion. A program was established and evaluated for treating persons with hemochromatosis in a donor center and making their blood available for transfusion. STUDY DESIGN AND METHODS: Phlebotomy therapy was performed free of charge regardless of whether subjects met criteria for allogeneic donation. A Hb level of 12.5 g per dL was used as the threshold for performing phlebotomy, and decreases in the MCV were used to guide the endpoints of therapy. RESULTS: A total of 130 subjects were consecutively enrolled: 74 percent were homozygous for the C282Y mutation in the HFE gene, 76 percent met eligibility criteria for allogeneic donation, and 55 percent were previous blood donors. A median of 20 weekly or biweekly phlebotomies (range, 7-99) were performed before the MCV reached the targeted endpoint of 3 percent below baseline, at which time the ferritin level was less than 30 microg per L and the transferrin saturation was less than 30 percent. The median phlebotomy interval necessary to keep the MCV at this level during maintenance therapy was 10 weeks. No incident seroconversions for agents of transfusion-transmissible disease occurred during 1402 donations. All subjects testing positive for viral agents gave a prior history of deferrable risk. Twenty-seven months after starting the program, hemochromatosis donors were contributing 14 percent of the RBC units collected for allogeneic use. CONCLUSIONS: Hemochromatosis subjects can safely and significantly augment the allogeneic blood supply. Provision of phlebotomy therapy unrestricted by considerations of cost or suitability for donation can improve access to care and remove incentives for incomplete risk disclosure.     

A survey of phlebotomy among persons with hemochromatosis

BACKGROUND: One in 10 whites in the United States is a carrier for hemochromatosis and an estimated 1 in 200 is clinically affected. Early treatment with therapeutic phlebotomy to remove excess iron can prevent associated chronic diseases. However, little information is available on the amount of blood withdrawn or the rates of withdrawal from hemochromatosis patients. The patterns of therapeutic phlebotomy and the magnitude of charges in persons with hemochromatosis were surveyed. STUDY DESIGN AND METHODS: Surveys were mailed to persons with hemochromatosis identified by health care providers, blood centers, patient advocacy groups, and the Internet. There were 2362 respondents to the survey from the United States. RESULTS: Thirty-seven percent of respondents reported being voluntary blood donors prior to diagnosis. The mean rate of therapeutic phlebotomy for iron depletion was 2.6 units per month (mean duration, 13 months). The mean rate of maintenance phlebotomy was 0.5 units per month.Therapeutic phlebotomy rates varied by sex, age, reason for diagnosis, and severity of symptoms. Seventy-six percent of respondents reported full or partial insurance coverage of therapeutic phlebotomy charges. Seventy-six percent received therapeutic phlebotomy services in a hospital or physician's office and 30 percent in a blood center. Charges for therapeutic phlebotomy varied by site, with a mean cost of $90 in hospitals and $52 in blood centers. Fifty-four percent of respondents attempted to donate blood after their diagnosis but were excluded. CONCLUSION: The amount of blood withdrawn from persons with hemochromatosis is substantial. The location where patients received phlebotomy services appears to be influenced by charges and time since diagnosis.     

Safety of autologous blood donation prior to elective surgery for a variety of potentially "high-risk" patients

We studied 342 potentially "high-risk" patients, including patients with severe heart disease, elderly patients, children, and pregnant women, to determine the incidence of complications related to phlebotomy. Our patients had an adverse reaction rate associated with blood donation of 4 percent, which is no greater than would be expected among normal volunteer blood donors. No patient experienced a dangerous complication associated with phlebotomy. We conclude that many patients currently denied the opportunity to donate blood preoperatively are actually suitable candidates for autologous blood transfusion programs.     

Safety and efficacy of preoperative donation of blood for autologous use by patients with end-stage heart or lung disease who are awaiting organ transplantation

Many patients are, perhaps inappropriately, denied the benefits of autologous blood transfusion, because they are thought to be too ill to donate blood safely. The safety and efficacy of autologous blood donation by selected patients with end-stage heart or lung disease who are awaiting organ transplantation were studied to determine if even these critically ill patients could be suitable candidates for autologous blood donation. Seventy-two adults awaiting heart or lung transplantation were evaluated for autologous blood donation in a hospital-based blood collection facility. Phlebotomy was performed if the patient met the required medical eligibility protocol, and if he or she consented to participate. Units of blood were separated into packed red cells and plasma and stored in a frozen state. Of 48 heart transplant candidates, 31 (65%) were each able to donate 1 to 8 units of blood. The median number of exposures to allogeneic components was 1 for patients who donated and 7 for nondonors (p = 0.0141). Among patients who donated, 54 percent required allogeneic components, as compared to 88 percent of nondonors (p = 0.0968). Of 24 lung transplant candidates, 15 (63%) made 1 to 6 donations each. The median number of exposures to allogeneic components was 0 for donors and 2 for nondonors (p = 0.1871), but only 45 percent of donors required allogeneic components, as compared to 100 percent of nondonors (p = 0.0418). No serious complications during or following phlebotomy were observed. It is concluded that autologous blood donation by patients with end-stage heart or lung disease may be safe.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effectiveness of the confidential unit exclusion option

BACKGROUND: The confidential unit exclusion (CUE) option is intended to reduce human immunodeficiency virus (HIV) transmission by excluding donors newly infected with HIV who have not yet developed HIV antibody (window-period donors); however, its efficacy in excluding window- period donors has not been evaluated. STUDY DESIGN AND METHODS: The use of the CUE option was studied among the donors of 3.7 million units at 18 American Red Cross blood services regions during 1991 and 1992 and among 322 previously HIV-1-seronegative donors who subsequently donated a seropositive unit between 1987 and 1990 at 40 United States blood centers. These seroconverting donors had previously been shown to be highly likely to donate during their window period. RESULTS: On the basis of data from these two populations, it was estimated that only 3 to 5 percent of units donated by window-period donors were not transfused because of the CUE option, that 0.4 percent of all donations were from donors who confidentially excluded their blood from transfusion, and that donors who confidentially excluded their blood were 21 times more likely to be HIV antibody-positive than donors who did not use the CUE option. It is estimated that, if all US blood centers used the CUE option, a total of 2 to 17 otherwise acceptable units donated by window-period donors would not be transfused annually. CONCLUSION: Although donors who confidentially exclude their blood from transfusion are 21 times more likely to have HIV antibody, the rarity of window-period donors and the infrequency of confidential exclusion by window-period donors cause the CUE option to have minimal impact on transfusion safety.     

Red cell concentrates of hemochromatosis patients comply with the storage guidelines for transfusion purposes

BACKGROUND: Therapeutic phlebotomy is the preferred treatment for iron overload associated with hemochromatosis. In the Netherlands, red blood cell concentrates (RCCs) from hemochromatosis patients are not used for transfusion purposes. In this study, their storage performance was compared with that of control donors as a first step in the evaluation of their potential usefulness for transfusion. STUDY DESIGN AND METHODS: RCCs were obtained from hemochromatosis patients and regular donors, either by apheresis or by whole-blood collection, and stored up to 50 days under routine Dutch blood bank conditions. Weekly samples were taken for determination of hematologic, biophysical, and biochemical variables. RESULTS: Most variables displayed the same storage-related changes in RCCs originating from hemochromatosis patients as in those from regular donors. In all RCCs, hemolysis remained well below the guideline limit of 0.8 percent for up to 6 weeks of storage, and the glucose concentration remained above the required 5 mmol per L up to 5 weeks of storage. After 4 weeks of storage, the mean ATP level remained above the required limit of 75 percent of the starting value in all RCCs as well. The major difference was a larger mean cell volume in hereditary hemochromatosis RBCs up to 50 days of storage. CONCLUSIONS: RCCs from hemochromatosis patients comply with the in vitro quality requirements for transfusion. This paves the way for the final step, namely, the establishment of the 24-hour RBC posttransfusion recovery.     

Preoperative autologous blood donation for bone marrow harvests: Are we wasting donors' time and blood?

Predeposit autologous blood donation (PAD) is frequently offered to bone marrow donors, but its cost-effectiveness is dubious. We assessed the impact of PAD and bone marrow donation on transfusion requirements; and the use of donated blood units in a retrospective study of 61 bone marrow donors. The mean haemoglobin (Hb) concentration fell from 12.9 to 11.8 g dL(-1) in women who predonated one unit and from 13.2 to 10.9 g dL(-1) in those who predonated two units. In men who donated two units of blood, the Hb concentration decreased to 12.9 g dL(-1). Bone marrow harvest led to a further decline in Hb concentration by 2.3 g dL(-1) in women and by 2.4 g dL(-1) in men. The postharvest Hb fell to or= 9.0 g dL(-1); overtransfusion was even more apparent in men: 71% units were given with a Hb >or= 10.0 g dL(-1). PAD in bone marrow donors is associated with high wastage and increases the likelihood of requiring a transfusion. We recommend that PAD should not be routinely offered to bone marrow donors.     

MCV as a guide to phlebotomy therapy for hemochromatosis

BACKGROUND: A multitude of recommendations exist for laboratory assays to monitor the pace and endpoints of phlebotomy therapy for hemochromatosis. All of these recommendations rely on an assessment of storage iron to guide treatment, and none have been prospectively evaluated. STUDY DESIGN AND METHODS: Nine consecutive patients underwent serial monitoring of Hb, MCV, transferrin saturation, and ferritin during weekly phlebotomy to deplete iron stores (induction therapy) and less frequent sessions to prevent iron reaccumulation (maintenance therapy). Changes in MCV and Hb were used to guide the pace of phlebotomy over a median of 7 years of follow-up. RESULTS: During induction therapy, the MCV increased transiently because of reticulocytosis and then stabilized for a prolonged period before decreasing more sharply, which reflected iron-limited erythropoiesis. Iron depletion was achieved after a median of 38 phlebotomies and removal of 9.0 g of iron. Maintenance phlebotomy was targeted to maintain the MCV at 5 to 10 percent below prephlebotomy values and the Hb at >13 g per dL. Transferrin saturation fluctuated considerably during treatment, but remained below 35 percent during MCV-guided maintenance therapy. Ferritin values were not useful guides to the pace of phlebotomy. The median maintenance therapy phlebotomy interval was 7.5 weeks (range, 6-16), which corresponded to an average daily iron removal of 35 to 67 microg per kg. Most patients showed evidence of iron reaccumulation at phlebotomy intervals of 8 weeks or more. CONCLUSION: The MCV is an inexpensive, precise, physiologic indicator of erythropoietic iron availability. When used in conjunction with the Hb, it is a clinically useful guide to the pace of phlebotomy therapy for hemochromatosis.     

Blood donation and transfusion practices: the 1990 American Association of Blood Banks Institutional Membership Questionnaire

Responses to the 1990 American Association of Blood Banks (AABB) Institutional Membership Questionnaire were submitted by 2126 regional blood centers, hospital-based blood banks, and transfusion facilities. Data from 2117 of these facilities were considered to be valid. The questionnaire included information on blood donor demographics, number of units collected, and collection procedures; services performed; usage of blood components; and transfusion-transmitted diseases reported during 1989. Institutional members collected 7.4 million whole blood units, of which 90.8 percent were donated for allogeneic use, 6.0 percent were donated for autologous use, and 3.2 percent were donated for directed use. Approximately 630,546 allogeneic and directed-use blood donors were deferred, most often for low hemoglobin or hematocrit values. Approximately 225,205 full allogeneic and directed-donor units were discarded, primarily for elevated alanine aminotransferase levels or the presence of hepatitis B core antibody. The 14.3 million transfused components included 56.7 percent red cell-containing components, 27.4 percent platelets, 11 percent fresh-frozen plasma, and 4.8 percent cryoprecipitate. Institutional members reported 1397 cases of transfusion-associated hepatitis. In this group, 921 patients were tested for hepatitis B surface antigen after the transfusion; 339 (36.8%) were found to be hepatitis B surface antigen positive. The AABB Institutional Questionnaire results provide recent data on blood donor and transfusion-related activities that are vital to the evaluation of current transfusion medicine practices.     

Who donates blood at five ethnically and geographically diverse blood centers in China in 2008

BACKGROUND: In China recruitment and retention of sufficient numbers of safe blood donors continues to be a challenge. Understanding who donates blood, particularly those who donate larger (>200 mL) whole blood (WB) units, will help blood centers to target more effective recruitment and retention strategies. STUDY DESIGN AND METHODS: Demographic characteristics of 226,489 allogeneic WB donors from January to December 2008 at five geographically and ethnically diverse, urban blood centers were analyzed. RESULTS: The typical Chinese WB donor can be characterized as first‐time volunteer (67.9%), male (56.9%), less than 45 years old (93.8%), and Han ethnicity (86.1%). Most donors had some college or below educational level (77.5%), donated at a mobile collection site (97.6%), and donated 300‐ or 400‐mL units (76.0%). Differences in WB volume donations and donor demographics exist among the five centers. CONCLUSION: In China compared to the United States, donations are made by younger donors and donors give infrequently and make smaller WB donations. To help ensure supply adequacy, continued efforts are needed to have donors give larger volumes of WB in China.     

Efficacy and safety of phlebotomy to reduce transfusional iron overload in adult, long-term survivors of acute leukemia

BACKGROUND: Transfusional iron overload is a frequent finding in long-term survivors of acute leukemia (AL). Only a few studies have reported the results of iron depletion therapy in this category of patients. STUDY DESIGN AND METHODS: Between January 1996 and July 2003, 26 consecutive adult patients who achieved complete remission of AL and developed transfusional iron overload underwent a weekly phlebotomy program at our transfusion center. Serum ferritin levels and transferrin saturation were monitored during the iron depletion therapy and the follow-up period. These AL patients were also checked for the presence of 12 hereditary hemochromatosis (HH) gene mutations. RESULTS: After a mean follow-up of 57.8 months, therapeutic phlebotomy (mean number of units collected, 36.6) was effective in reducing mean ferritin concentration and transferrin saturation from 1726.9 to 93.0 mg per L and from 54.7 to 23.3 percent, respectively. The presence of a HH gene mutation did not influence initial iron status or response to treatment. The phlebotomy program was well tolerated and no adverse events were recorded during or after collection. In three cases the time between phlebotomies was increased because of patient's poor compliance or low Hb levels. CONCLUSION: Our study shows that phlebotomies are a safe and effective method for reducing iron over-load in multiply transfused long-term AL survivors with secondary hemochromatosis.     

Should cardiac disease prevent autologous blood donation?

AIDS has created considerable concern among the public regarding being transfused with potentially infectious blood. However, autologous blood donations are still not maximally provided nor utilized. Significant heart disease disqualifies all allogeneic and most autologous blood donors (American Association of Blood Banks (AABB) Standards 1994). Disqualification is based on the widespread belief that donating blood could possibly be detrimental to their health. However, this belief has not been sufficiently documented. Sixty-eight donors (ages 14-84 years), all with histories of significant cardiac diseases, donated 111 units of whole blood (1-3 units). Twenty-eight patients donated 1 unit, 37 donated 2 units, and three patients donated 3 units. Fifty-nine patients had ischemic heart disease, and nine had valvular heart disease (five with mitral stenosis and four with mitral valve prolapse). No patient received erythropoietin, and only one received equal volume replacement with normal saline during donation. All these patients eagerly wished to donate in spite of being informed of the possible complications. No patient wishing to donate has been refused, and none has experienced any adverse consequences from donating. Forty-four patients underwent total hip/knee replacements. Only 56 units (50%) were transfused to 37 patients (54%). Although our experience is limited, it appears that many patients with histories of well established cardiac diseases can easily tolerate donating blood without compromising their health.     

A national survey of transfusion‐related acute lung injury risk reduction policies for platelets and plasma in the United States

BACKGROUND: Little information exists on the specific transfusion‐related acute lung injury (TRALI) risk reduction practices used by multiple blood collecting institutions in the United States. STUDY DESIGN AND METHODS: An AABB‐appointed TRALI working group designed a set of questions about TRALI risk reduction for platelets (PLTs) and plasma. AABB member institutions were asked to respond via an Internet‐based survey during a 3‐week period in August through September 2009. RESULTS: Valid responses were received from 47 US blood centers (accounting for 1.57 million apheresis PLT units and 3.15 million whole blood–derived transfusable plasma units) and 56 hospital blood collectors. Among the blood centers, 87 and 98% had initiated some PLT and plasma risk reduction, respectively. HLA antibody testing of plateletpheresis donors was performed by 20 (43%) blood centers. There was substantial variation in the number of pregnancies (from one to more than four) that triggered testing and most centers did not screen based on a transfusion history. Almost all centers had policies to redirect HLA antibody–positive donors to whole blood donation and to potentially retest HLA antibody–negative donors. There were no blood centers performing HNA antibody testing. Sex‐based risk reduction policies for plasma included all male, or predominantly male, and never‐pregnant females; these varied by blood center, blood group, and method of plasma collection. A majority of centers indicated increased production of plasma frozen within 24 hours after phlebotomy. CONCLUSIONS: Almost 3 years after the publication of the initial AABB bulletin on this issue, TRALI risk reduction strategies are commonly employed at most US blood centers. However, procedures are not uniform.     

Influence of phlebotomy treatment on abnormal hypothalamic-pituitary function in genetic hemochromatosis

To test the hypothesis that deficiencies in hypothalamic-pituitary function in genetic hemochromatosis result from cellular injury by iron deposits, we conducted provocative tests in 11 men with genetic hemochromatosis before and after iron depletion by serial phlebotomy and in 10 control subjects. We gave combination intravenous injections of insulin (0.15 U/kg), luteinizing hormone releasing hormone (LHRH, 100 micrograms), and thyrotropin releasing hormone (400 micrograms) and then measured plasma glucose, growth hormone, corticosteroids, follicle-stimulating hormone, luteinizing hormone, prolactin, and thyroid-stimulating hormone at 30-minute intervals for 90 minutes. Phlebotomy caused a substantial decrease in median values for serum ferritin, deferoxamine-chelatable iron, and hepatic iron concentration. Before phlebotomy, stimulation by hypoglycemia and thyrotropin releasing hormone caused significantly less secretion of growth hormone (P = 0.004) and prolactin (P = 0.03) in patients than in control subjects. No significant improvement was noted, however, in growth hormone or prolactin secretion after phlebotomy. Of the 11 patients, 7 had secondary hypogonadism, and phlebotomy did not improve the serum testosterone, follicle-stimulating hormone, luteinizing hormone, or responses to LHRH in any case. Chlorpromazine injections failed to elevate serum prolactin in all patients, and administration of levodopa caused a partial reduction in serum prolactin; thus, the hypothalamus may be an important locus of endocrine malfunction in these patients. We conclude that abnormal hypothalamic-pituitary function in genetic hemochromatosis is not substantially improved by iron-depletion therapy.     

Peripheral blood erythrocyte parameters in hemochromatosis: evidence for increased erythrocyte hemoglobin content

We studied peripheral blood erythrocyte parameters and HFE genotypes in 94 hemochromatosis probands and 132 white, normal control subjects. Mean red blood cell counts in probands and control subjects were not significantly different. However, mean values of hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were significantly higher in C282Y/C282Y probands (n = 60) than in wild-type control subjects (n = 65). Probands with other HFE genotypes also had increased mean erythrocyte parameters (other than red blood cell count). Peripheral blood smears prepared before therapeutic phlebotomy revealed that erythrocytes in many probands had increased diameters and were well filled with hemoglobin. Erythrocyte parameters were similar in C282Y/C282Y probands with and without hepatomegaly, elevated serum concentrations of hepatic enzymes, hepatic cirrhosis, diabetes mellitus, arthropathy, or hypogonadism. Among C282Y/C282Y probands, significantly greater values of MCV (but not other erythrocyte parameters) occurred among those who had transferrin saturation values of 75% or greater or iron overload at diagnosis. After iron depletion, the mean MCV, MCH, and MCHC values of C282Y/C282Y probands decreased but remained significantly greater than values in wild-type control subjects. Mean values of prephlebotomy MCH and MCHC concentrations were lower in HLA-A3-positive than in HLA-A3-negative C282Y/C282Y probands. We conclude that increased values of mean hemoglobin, hematocrit, MCV, MCH, and MCHC in hemochromatosis probands are caused primarily by increased iron uptake and hemoglobin synthesis by immature erythroid cells. Mechanisms of iron uptake by erythrocytes that could explain these results are discussed.     

Metabolomics of ADSOL (AS-1) Red Blood Cell Storage

Population-based investigations suggest that red blood cells (RBCs) are therapeutically effective when collected, processed, and stored for up to 42 days under validated conditions before transfusion. However, some retrospective clinical studies have shown worse patient outcomes when transfused RBCs have been stored for the longest times. Furthermore, studies of RBC persistence in the circulation after transfusion have suggested that considerable donor-to-donor variability exists and may affect transfusion efficacy. To understand the limitations of current blood storage technologies and to develop approaches to improve RBC storage and transfusion efficacy, we investigated the global metabolic alterations that occur when RBCs are stored in AS-1 (AS1-RBC). Leukoreduced AS1-RBC units prepared from 9 volunteer research donors (12 total donated units) were serially sampled for metabolomics analysis over 42 days of refrigerated storage. Samples were tested by gas chromatography/mass spectrometry and liquid chromatography/tandem mass spectrometry, and specific biochemical compounds were identified by comparison to a library of purified standards. Over 3 experiments, 185 to 264 defined metabolites were quantified in stored RBC samples. Kinetic changes in these biochemicals confirmed known alterations in glycolysis and other pathways previously identified in RBCs stored in saline, adenine, glucose and mannitol solution (SAGM-RBC). Furthermore, we identified additional alterations not previously seen in SAGM-RBCs (eg, stable pentose phosphate pathway flux, progressive decreases in oxidized glutathione), and we delineated changes occurring in other metabolic pathways not previously studied (eg, S-adenosyl methionine cycle). These data are presented in the context of a detailed comparison with previous studies of SAGM-RBCs from human donors and murine AS1-RBCs. Global metabolic profiling of AS1-RBCs revealed a number of biochemical alterations in stored blood that may affect RBC viability during storage as well as therapeutic effectiveness of stored RBCs in transfusion recipients. These results provide future opportunities to more clearly pinpoint the metabolic defects during RBC storage, to identify biomarkers for donor screening and prerelease RBC testing, and to develop improved RBC storage solutions and methodologies.     

广东籍献血人群HTLV感染状况调查

目的了解东南沿海省份的元症状献血人群人类嗜T淋巴细胞病毒（human T cell lymphotvopic virus,HTLV）的血清学流行状况。方法从符合卫生部健康标准并经血液常规检测合格的标本中,依据籍贯选择性收集2500份血样,采用双抗原夹心的酶免吸附（EIA）方法进行HTLV-Ⅰ／Ⅱ抗体筛查。EIA初筛阳性结果经复检后,由蛋白印迹法（Western Blot,WB）进行确认试验。结果初筛获得EIA反应性样本5例,HTLV抗体阳性率为0．20％（5／2500）,均为广东籍。经蛋白印迹试验,仅1例OD值为3．00的EIA强反应者获确认为HTLV—Ⅰ型病毒感染,2例未获确认,2例为确认阴性。经追溯,确认HTLV—Ⅰ阳性者为无症状定期献血者,已有6次合格献血经历。结论尽管深圳献血人群HTLV流行率的总体水平较低,但多次献血的经历使经血传播HTLV的风险增大数倍。     

Efficacy of preoperative donation of blood for autologous use in radical prostatectomy

To determine the amount of blood lost, the number of transfusions, and the effectiveness of preoperative autologous blood donation in radical prostatectomy, 163 patients' records from 1987 to 1991 were reviewed at four university hospitals and three community hospitals. Calculated red cell volume lost was 1003 +/− 535 mL (mean +/− SD), which corresponds to 44 +/− 18 percent (mean +/− SD) of total red cell volume. Preoperative donation of blood for autologous use reduced the rate of transfusion of allogeneic blood from 66 to 20 percent (p < 0.001). Of the patients who donated 1 to 2 units, 32 percent received allogeneic blood; 14 percent of those who donated 3 units received allogeneic blood. Donation of 4 units reduced the allogeneic transfusion rate to 11 percent. However, as the number of units donated increased (1-3 units), the units not transfused also increased (0-21%). Ninety-one (56%) of 163 patients donated fewer than 3 units. Autologous blood donation is effective in minimizing the transfusion of allogeneic blood to radical prostatectomy patients, but many patients do not donate enough blood (< 3 units). The donation of 3 units of blood for autologous use is recommended for patients who undergo radical prostatectomy.     

Blood donation and patterns of use in southeastern Nigeria

A retrospective study of donor blood availability and patterns of use from 1984 through 1988 was conducted in a 400-bed university teaching hospital in Nigeria by extraction of data from the master registers for blood donors and recipients. Blood transfusion requests, number of persons who underwent phlebotomy, number of crossmatches performed, and blood use increased each year during the period of study. Average wastage rate and crossmatch-to-transfusion ratio were 3.5 percent and 1.61, respectively. Replacement blood donation constituted 98 percent of available donor blood. Obstetrics and gynecology and surgery patients used 70.4 percent of the donor blood. The donor blood units were used as whole blood (81%) because of a lack of infrastructure such as a refrigerated centrifuge. Less than 5 percent of the donors were females. It is concluded that the levels of voluntary blood donation and general blood supply are unacceptably low. The need for a functional National Blood Transfusion Service is highlighted.