Validation and development of an immunonephelometric assay for the determination of alpha-1 antitrypsin levels in dried blood spots from patients with COPD

OBJECTIVE:

To validate and develop an immunonephelometric assay for the determination of alpha-1 antitrypsin (AAT) levels in dried blood spots from COPD patients in Brazil.

METHODS:

We determined AAT levels in serum samples and dried blood spots from 192 COPD patients. For the preparation of dried blood spots, a disk (diameter, 6 mm) was placed into a tube, eluted with 200 µL of PBS, and stored overnight at 4ºC. All of the samples were analyzed by immunonephelometry in duplicate. We used the bootstrap resampling method in order to determine a cut-off point for AAT levels in dried blood spots.

RESULTS:

The correlation coefficient between the AAT levels in serum samples and those in dried blood spots was r = 0.45. For dried blood spots, the cut-off value was 2.02 mg/dL (97% CI: 1.45-2.64 mg/dL), with a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 95.7%, 27.2%, and 100%, respectively.

CONCLUSIONS:

This method for the determination of AAT levels in dried blood spots appears to be a reliable screening tool for patients with AAT deficiency.     

Monitoring compliance with transfusion guidelines in hospital departments by electronic data capture

Background

The practice of transfusing red blood cells is still liberal in some centres suggesting a lack of compliance with guidelines recommending transfusion of red blood cells at haemoglobin levels of 6–8 g/dL in the non-bleeding patient. Few databases provide ongoing feedback of data on pre-transfusion haemoglobin levels at the departmental level. In a tertiary care hospital, no such data were produced before this study. Our aim was to establish a Patient Blood Management database based on electronic data capture in order to monitor compliance with transfusion guidelines at departmental and hospital levels.

Materials and methods

Hospital data on admissions, diagnoses and surgical procedures were used to define the populations of patients. Data on haemoglobin measurements and red blood cell transfusions were used to calculate pre-transfusion haemoglobin, percentage of transfused patients and transfusion volumes.

Results

The model dataset include 33,587 admissions, of which 10% had received at least one unit of red blood cells. Haemoglobin measurements preceded 96.7% of the units transfused. The median pre-transfusion haemoglobin was 8.9 g/dL (interquartile range 8.2–9.7) at the hospital level. In only 6.5% of the cases, transfusion was initiated at 7.3 g/dL or lower as recommended by the Danish national transfusion guideline. In 27% of the cases, transfusion was initiated when the haemoglobin level was 9.3 g/dL or higher, which is not recommended. A median of two units was transfused per transfusion episode and per hospital admission. Transfusion practice was more liberal in surgical and intensive care units than in medical departments.

Discussion

We described pre-transfusion haemoglobin levels, transfusion rates and volumes at hospital and departmental levels, and in surgical subpopulations. Initial data revealed an extensive liberal practice and low compliance with national transfusion guidelines, and identified wards in need of intervention.     

A non-invasive strategy for haemoglobin screening of blood donors

Introduction

Assessing blood-donor haemoglobin (Hb) is a worldwide screening requirement against inappropriate donation. The pre-donation Hb (which should be at least 12.5 g/dL in women and 13.5 g/dL in men) is usually determined in capillary blood from a finger prick, using a spectrophotometer which reveals the absorbance of blood haemolysed in a microcuvette. New non-invasive methods of measuring Hb are now available.

Materials and methods

In the first semester of 3 consecutive years three different strategies were employed to screen donors for anaemia at the moment of donation. In 2011 all whole-blood donors underwent the finger-prick method using azide-methaemoglobin: the test’s negative predictive value (NPV) was determined by comparison with the sub-threshold Hb values ascertained by haemocytometry of test-tube blood drawn at the start of the donation. In 2012 the donor evaluation was based on NBM 200 occlusion spectrophotometry. The same approach was kept in 2013, but a haemocytometry test was added on a pre-donation venous sample drawn from donors who, though fit to donate, had previous critical Hb values in their clinical records.

Results

In 2011, the NPV (in 3,856 donors) was 86% for women and 95% for men; in 2012 (3,966 donors), the values were 85% and 95%, respectively, and in 2013 (3,995 donors) they were 91% and 97%, respectively. Fisher’s test for contingency tables revealed no statistically significant differences between 2011 and 2012, but the 2013 results were a significant improvement.

Discussion

Measuring Hb by finger prick is not wholly satisfactory since, above all in women, the result of this screening may subsequently be belied by the haemocytometry finding of an unacceptable Hb value. Using a non-invasive method does not diminish the selective efficiency. In women, in particular, adding a haemocytometric test on a venous sample significantly improves donor selection and avoids the risk of inappropriate donation or blood-letting.     

FreeStyle Mini? Blood Glucose Results Are Accurate and Suitable for Use in Glycemic Clamp Protocols

Objective

We assessed the accuracy of the FreeStyle Mini™ (FSM) meter for use in glycemic clamp and meal protocols in comparison with the HemoCue Glucose 201 DM Analyzer (HemoCue) and the YSI 2300 STAT Glucose Oxidase Analyzer (YSI).

Methods

Seven volunteers with type 2 diabetes mellitus, 35–69 years old, underwent a frequently sampled meal test and a graded hyperglycemic test, on two separate days, with one of the volunteers undergoing each test twice. Samples for glucose measurements were obtained from arterialized venous blood. A total of 420 samples (with glucose levels ranging from 63 to 388 mg/dl) were available for comparison. On average, 10 measurements were available for every 5 mg/dl increment in glucose level in the range of 130–310 mg/dl. Blood glucose measurements were done on each sample with the FSM, HemoCue, and YSI.

Results

FreeStyle Mini blood glucose values correlated closely with the YSI readings. Of the FSM measurements, 99.0% were within the Clarke error grid zone A; 51.3%, 84.7%, and 96.2% of the FSM readings were within 5%, 10% and 15% of the YSI values, respectively. The FSM was significantly more accurate than the HemoCue (84.7% vs 76.6% of results within 10% of the YSI results; p = .0038). The mean average relative difference of the FSM (5.8%) was also significantly lower than that of the HemoCue (6.8%; p = .0013)

Conclusions

The FSM provides accurate results and constitutes a suitable alternative for bedside blood glucose measurements in experimental procedures, helping to reduce sample size, turnaround time, and cost.     

Oxidative injury as contributory factor for red cells storage lesion during twenty eight days of storage

Background

Storage of red blood cells at 4 °C is associated with deleterious metabolic and biochemical changes, collectively referred to as “storage lesions”. Lipid peroxidation of the red cell membrane leading to lysis contributes to these storage lesions. The aim of the present study was to investigate oxidative injury to red cells during storage for 28 days and its correlation with markers of red cell membrane damage.

Materials and methods

Samples from 30 units of red blood cells stored at 4 °C for 28 days were withdrawn aseptically on day 0, day 14 and day 28 of storage. Markers of membrane damage including plasma haemoglobin, plasma potassium and lactate dehydrogenase (LDH) concentrations and markers of oxidative injury such as malondialdehyde (MDA) levels, haemoglobin oxidation and osmotic fragility were studied in all samples.

Results

Statistically significant (p<0.001) increases in the mean values of plasma haemoglobin, plasma potassium, LDH and markers of oxidative injury such as MDA and haemoglobin oxidation were observed over the storage period of 28 days. Direct correlations of MDA and haemoglobin oxidation with membrane damage, as reflected by plasma haemoglobin concentration, were observed.

Conclusion

Oxidative injury to red blood cells during storage leads to membrane damage and lysis. The role of antioxidants in the prevention of this deleterious effect of storage warrants investigation.     

Determining the volume of blood required for the correction of foetal anaemia by intrauterine transfusion during pregnancies of Rh isoimmunised women

Background

Severe anaemic foetuses of Rhesus (Rh) isoimmunised mothers are usually treated by intrauterine transfusion (IUT). It is helpful to determine the volume of blood necessary to raise the concentration of haemoglobin by 1.0 g/dL in response to intrauterine transfusions.

Methods

In this cross-sectional, observational study we evaluated 107 first IUT for the correction of anaemia caused by haemolysis triggered by maternal Rh immunisation. The concentration of foetal haemoglobin was determined in umbilical cord blood before and after the IUT. The variation in foetal concentration of haemoglobin after transfusion was compared between groups of hydropic and non-hydropic foetuses, between groups of foetuses with different degrees of anaemia and with groups of gestational age less than or more than 28 weeks. The t-test for averages and ANOVA were used to compare average differences among the groups. p values less than 0.05 were considered statistically significant.

Results

Fifty-five (61.4%) foetuses were found to be anaemic while hydrops was observed in 40 (44%) at the time of the IUT. The volume of red blood cell concentrate infused varied from 5 to 90 mL, with 11.2±1.5 mL being necessary to raise the circulating concentration of haemoglobin by 1.0 g/dL. The foetal response was not influenced significantly by either the degree of foetal anaemia (p=0.56) or the presence of hydrops (p=0.17). The foetuses with a gestational age of 28 weeks or less required a smaller volume of red blood cell concentrate than those with a gestational age of more than 28 weeks (9.3±5.4 mL and 13.4±4.8 mL, respectively; p<0.0001) in order to raise their concentration of circulating haemoglobin by 1.0 g/dL.

Conclusion

The volume of red blood cell concentrate necessary to correct anaemia in pregnancies complicated by Rh isoimmunisation must be considered carefully, since the response to the infusion of blood is peculiar in extremely premature infants. Hydrops and the degree of anaemia were not determinants of the change in the final concentration of circulating haemoglobin following the blood transfusion.     

Sickle cell disease in areas of immigration of high-risk populations: a low cost and reproducible method of screening in northern Italy

Background

From 2005 to 2010, we observed a 10-fold increase of newly diagnosed sickle cell disease in children in the province of Modena (northern Italy). The median age at diagnosis was 24 months. Since these children are too old for optimal disease management, earlier detection of the disease is needed for prophylaxis and comprehensive care before the occurrence of clinical manifestations.

Materials and methods

In each Maternity Unit of the province of Modena, blood samples are collected daily for assessment of haemolytic disease of the newborn. We designed a selective, low-cost haemoglobin screening for sickle cell disease in high-risk immigrants. We enrolled 469 mothers from sub-Saharan countries and their neonates for a primary screening of peripheral blood haemoglobin variants using high-performance liquid chromatography.

Results

Of the 469 women approached, 330 (70.36%) agreed to undergo the test. Ninety-two (27.88%) were carriers of variant haemoglobin, 48 newborns (51%) of these carriers had the carrier trait and 9 (9.6%) were affected (haemoglobin SC compound heterozigote - HbSC, haemoglobin S homozygote - HbSS).

Discussion

These results support the feasibility and usefulness of a selective screening for the detection of haemoglobin variants in high-risk subjects in an area in which sickle cells disease is not endogenous. We achieved the goal of detecting subjects with carrier trait/disease in order to implement preventive measures that reduce the clinical manifestations of sickle cell disease. We are, however, aware that it will be necessary to extend this screening to the overall population in the near future.     

The need to label red blood cell units with their haemoglobin content: a single centre study on haemoglobin variations due to donor-related factors

Background

Red blood cell (RBC) transfusions are given as “number of units” without considering the haemoglobin (Hb) content of these units. Donor factors influencing Hb level in whole blood donors and, ultimately, in RBC units have not been studied.

Materials and methods

Donor data for a period of 1.5 years were retrospectively analysed and the effects of age, gender and weight on the Hb level of the donors were determined. The correlation between donor’s Hb concentration with total Hb in the RBC unit was analysed. Additionally, actual Hb content of 125 RBC units was determined. The total Hb content of these RBC units was also mathematically calculated based on the blood donors’ Hb. The ability of this mathematically calculated Hb to predict actual Hb content per RBC unit was then analysed.

Results

The mean Hb level in female donors was 1.79 g/dL lower than in the male donors (p<0.001). Increasing age was associated with a lower mean Hb in the donors (p<0.01), while a higher body weight correlated weakly (r=0.06) but significantly with increased mean Hb (p<0.01). Logistic regression analysis showed that in blood donors, female gender had a stronger influence on lowering the mean Hb than either older age or lower weight. A variation of nearly 100% (42.3–80.8 g Hb per unit) was seen in the total Hb content of the RBC units tested. Mathematically calculated Hb content correlated well (r=0.6; p<0.01) with the actual Hb content of the RBC units.

Discussion

We demonstrated the effect of gender, age and weight on Hb levels in whole blood donors. Dissimilarities in the donor Hb caused nearly 100% variations in the Hb content of the RBC units. It would, therefore, be prudent to label RBC units with their total Hb content. This total Hb content can be predicted fairly accurately from the donor’s pre-donation Hb level.     

Splenectomy improves anaemia but does not reduce iron burden in patients with haemoglobin H Constant Spring disease

Background

Splenectomy is reported to increase the haemoglobin level in patients with haemoglobin H Constant Spring (HbH CS) disease; however, its impact on iron burden and the underlying mechanism remains unclear.

Materials and methods

From March through to May 2013, a total of 50 adults with HbH CS disease (25 cases splenectomised and 25 cases non-splenectomised) were enrolled. The patients’ general conditions, history of blood transfusion and iron chelator treatment were investigated. Levels of haemoglobin, nucleated red blood cell counts, and serum ferritin were measured. The percentage of apoptotic erythroid precursor cells in bone marrow, an index representing ineffective erythropoiesis, was determined in some cases.

Results

There were no significant differences in age, blood transfusion volume, and use of iron chelator drugs between the splenectomised group and the non-splenectomised group. Significantly higher haemoglobin levels, serum ferritin levels and nucleated red blood cell counts as well as a higher percentage of apoptotic erythroid progenitor cells were detected in the splenectomised group. Regression analysis revealed that age and nucleated red blood cell counts were independent risk factors affecting the serum ferritin level.

Discussion

Despite improving the haemoglobin level, splenectomy is associated with greater iron burden in HbH CS disease. A high nucleated red blood cell count is predictive of the risk of severe iron overload.     

Pre- and post- donation haematological values in healthy donors undergoing plateletpheresis with five different systems

Background

Although automated cell separators have undergone a lot of technical refinements, attention has been focused more on the quality of platelet concentrates than on donor safety. We planned this prospective study to observe the effects of automated plateletpheresis on normal haematological values of healthy donors and to determine whether the haematological alterations had any clinical consequences.

Study design and methods

The study was conducted on 457 healthy, first-time plateletpheresis donors over a period of 26 months. The plateletpheresis procedures were performed using five different cell separators and various pre- and post-donation haematological values such as haemoglobin concentration (Hb), haematocrit (Hct), platelet and white blood cell (WBC) counts, mean platelet volume and platelet distribution width were measured in all donors.

Results

We observed that the Hb, Hct, platelet and WBC counts decreased significantly in the donors (p<0.01) after each procedure, without there being significant changes in mean platelet volume or platelet distribution width. The decreases in Hb and Hct were significantly greater with the CS 3000 and Amicus machines, while the decreases in platelet and WBC counts were significantly greater with the CS 3000 and Fresenius separators.

Conclusion

Although a significant drop in complete blood count was observed in all donors, none manifested features of thrombocytopenia or anaemia. Nevertheless, more prospective studies on this aspect are required in order to establish guidelines for donor safety in apheresis and also to help in assessing donor suitability, especially given the present trend of double product apheresis collections.     

Blood management by transfusion triggers: when less is more

Background

We reviewed the annual blood utilisation data at our institution for the past 6 years. The number of packed red blood cell units for allogeneic transfusions gradually increased from 3,989 (in 2004) to 4,762 (in 2008): a 19% increase. This exceeded the 7% increase in annual admissions of patients during the same period (from 20,470 in 2004 to 21,908 in 2005).

Materials and methods

In 2009, we introduced new transfusion guidelines (“triggers”), essentially adopting the recommendations of the Society for the Advancement of Blood Management. Most importantly, we reduced the trigger of blood transfusions in normovolaemic symptomatic chronic anaemia patients from 8 to 7 g/dL haemoglobin. At the same time, we created a new trigger of 9 g/dL haemoglobin for high-risk patients (e.g. those with cardiovascular and/or chronic pulmonary disease as well as those undergoing chemotherapy).

Results

We monitored the indications for blood transfusions during 2009 (2,717 consecutive orders) and sent out letters of reminder of the new guidelines to our clinicians if criteria were not met (a total of 102 letters, representing 4% of the reviewed orders). Our annual blood utilisation in 2009 showed some improvement (4,648 units) compared to the previous year (4,762 units) despite the increase in admissions of patients (from 21,908 to 22,734): this represents a 6% decrease in blood utilisation when corrected for the admissions of patients. If this trends holds up, the predicted blood utilisation for 2010 based on the January to November data (4,280) promises to show a further improvement (an 11% decrease compared to 2008).

Discussion

We conclude that blood utilisation may be improved in a community hospital setting by combining new, evidence-based transfusion triggers with physicians’ education.     

Predictors of blood transfusion requirement in elective liver resection

Background:

Liver resection remains major surgery frequently requiring intra-operative blood transfusion. Patients are typically over cross-matched, and with blood donor numbers falling, cross-matching and transfusion policies need rationalizing.

Aim:

To identify predictors of peri-operative blood transfusion.

Methods:

A retrospective review of elective hepatic resections over a 4-year period was performed. Twenty-six variables including clinicopathological variables and intra-operative data were collated, together with the number of units of blood cross-matched and transfused in the immediate peri-operative period (48 h). Multivariate regression analysis was performed to identify independent predictors of blood transfusion, and a Risk Score for transfusion constructed.

Results:

Five hundred and eighty-nine patients were included in the study, and were cross-matched with a median 10 units of blood. Seventeen per cent of patients received a blood transfusion; median transfusion when required was 2 units. Regression analysis identified seven factors predictive of transfusion: haemoglobin <12.5 g/dL, pre-operative biliary drainage, coronary artery disease, largest tumour >3.5 cm, cholangiocarcinoma, redo resection and extended resection (5+ segments). Patients were stratified into high or low risk of transfusion based on Risk Score with a sensitivity of 73% [receiver-operating characteristic (ROC) 0.77].

Conclusions:

Patients undergoing elective liver resection are over-cross-matched. Patients can be classified into high and low risk of transfusion using a Risk Score, and cross-matched accordingly.     

Jk(a?b?) phenotype screening by the urea lysis test in Thai blood donors

Background

The Jk(a−b−) phenotype is rare in most populations and often detected after transfusion or pregnancy. After immunisation, anti-Jk3 forms and it can be difficult to find compatible Jk(a−b−) donors. Using anti-Jk^a and anti-Jk^b in a conventional tube method is unsuitable for identifying Jk(a−b−) in mass screening of blood donors. Jk(a−b−) phenotypes are associated with the absence of urea transporters on erythrocytes, making red blood cells (RBC) resistant to lysis by 2M urea, while Jk(a+b−), Jk(a−b+) and Jk(a+b+) phenotypes are susceptible to lysis.

Materials and methods.

We screened for Jk(a−b−) phenotypes in blood donors by the urea lysis test using a 96-well microplate. The Jk(a−b−) phenotypes were confirmed by the indirect antiglobulin test (IAT).

Results

Altogether, 20,163 blood samples from Thai blood donors were tested and only RBC from five samples were resistant to lysis by 2M urea, while 20,158 samples were completely lysed within 5 min. In an IAT, both anti-Jk^a and anti-Jk^b failed to agglutinate RBC from all five samples. Using a micro-titre plate, the direct urea lysis test, costs • 0.01, about 480 times less than IAT. Moreover, the test time for each plate (94 samples) is about 18 times less than that for IAT.

Conclusion

Jk(a−b−) phenotype screening by the direct urea lysis test on samples in a micro-titre plate is simple, cost-effective and practical for mass screening of blood donors.     

The JAK2V617F tyrosine kinase mutation in blood donors with upper-limit haematocrit levels

Background

It is not rare to observe in blood donors a level of haematocrit (Hct) above or close to the highest normal limit. In the case of blood donors the diagnosis and clinical evaluation of this alteration may be complicated by regular blood donations that can mask an underlying disease such as polycythaemia vera. Recently a single acquired mutation in the Janus kinase 2 gene (JAK2) on chromosome 9 was identified and it was found that the incidence of this mutation was high in patients with polycythaemia vera.

Material and Methods

From the January 1, 2006 to December 31, 2006 all consecutive donors with a Hct above 50% if males (n=84) and 46% if females (n=19) underwent JAK2 mutation analysis. Seventy-nine donors (59 males and 20 females) whose Hct was normal at their last blood donation were randomly selected and used as controls.

Results

Among the group of blood donors with a high Hct, we identified one donor who was positive for the JAK2 mutation. This man had a Hct of 50.6% at his last donation, while his average Hct in the preceding year was 51.7%. The prevalence of the JAK2 mutation could be estimated to be 1%, 0.6% or 0.02% in the three different populations considered: donors with a Hct level above the upper limit of normal, all tested donors or the entire donor cohort attending our transfusion service, respectively.

Conclusions

The present study suggests that apparently healthy subjects with repeatedly high levels of Hct may have the acquired mutation in JAK2. Laboratory screening tests for JAK2 may be offered to blood donors at transfusion services with expertise in molecular genetics.     

A fast-track anaemia clinic in the Emergency Department: feasibility and efficacy of intravenous iron administration for treating sub-acute iron deficiency anaemia

Background

Clinically significant anaemia, requiring red blood cell transfusions, is frequently observed in Emergency Departments (ED). To optimise blood product use, we developed a clinical protocol for the management of iron-deficiency anaemia in a fast-track anaemia clinic within the ED.

Materials and methods

From November 2010 to January 2014, patients presenting with sub-acute, moderate-to-severe anaemia (haemoglobin [Hb] <11 g/dL) and confirmed or suspected iron deficiency were referred to the fast-track anaemia clinic. Those with absolute or functional iron deficiency were given intravenous (IV) ferric carboxymaltose 500–1,000 mg/week and were reassessed 4 weeks after receiving the total iron dose. The primary study outcome was the haematological response (Hb≥12 g/dL and/or Hb increment ≥2 g/dL). Changes in blood and iron parameters, transfusion rates and IV iron-related adverse drug effects were secondary outcomes.

Results

Two hundred and two anaemic patients with iron deficiency (150 women/52 men; mean age, 64 years) were managed in the fast-track anaemia clinic, and received a median IV iron dose of 1,500 mg (1,000–2,000 mg). Gastro-intestinal (44%) or gynaecological (26%) bleeding was the most frequent cause of the anaemia. At follow-up (183 patients), the mean Hb increment was 3.9±2.2 g/dL; 84% of patients were classified as responders and blood and iron parameters normalised in 90%. During follow-up, 35 (17%) patients needed transfusions (2 [range: 1–3] units per patient) because they had low Hb levels, symptoms of anaemia and/or were at risk. Eight mild and one moderate, self-limited adverse drug effects were witnessed.

Discussion

Our data support the feasibility of a clinical protocol for management of sub-acute anaemia with IV iron in the ED. IV iron was efficacious, safe and well tolerated. Early management of anaemia will improve the use of blood products in the ED.     

Phosphatidylserine exposure on stored red blood cells as a parameter for donor-dependent variation in product quality

Background

Exposure of phosphatidylserine on the outside of red blood cells contributes to recognition and removal of old and damaged cells. The fraction of phosphatidylserine-exposing red blood cells varies between donors, and increases in red blood cell concentrates during storage. The susceptibility of red blood cells to stress-induced phosphatidylserine exposure increases with storage. Phosphatidylserine exposure may, therefore, constitute a link between donor variation and the quality of red blood cell concentrates.

Materials and methods

In order to examine the relationship between storage parameters and donor characteristics, the percentage of phosphatidylserine-exposing red blood cells was measured in red blood cell concentrates during storage and in fresh red blood cells from blood bank donors. The percentage of phosphatidylserine-exposing red blood cells was compared with red blood cell susceptibility to osmotic stress-induced phosphatidylserine exposure in vitro, with the regular red blood cell concentrate quality parameters, and with the donor characteristics age, body mass index, haemoglobin level, gender and blood group.

Results

Phosphatidylserine exposure varies between donors, both on red blood cells freshly isolated from the blood, and on red blood cells in red blood cell concentrates. Phosphatidylserine exposure increases with storage time, and is correlated with stress-induced phosphatidylserine exposure. Increased phosphatidylserine exposure during storage was found to be associated with haemolysis and vesicle concentration in red blood cell concentrates. The percentage of phosphatidylserine-exposing red blood cells showed a positive correlation with the plasma haemoglobin concentration of the donor.

Discussion

The fraction of phosphatidylserine-exposing red blood cells is a parameter of red blood cell integrity in red blood cell concentrates and may be an indicator of red blood cell survival after transfusion. Measurement of phosphatidylserine exposure may be useful in the selection of donors and red blood cell concentrates for specific groups of patients.     

Sexual behaviour of Croatian blood donors as a threat to the health of blood recipients

Background

In this cross-sectional study we assessed the prevalence of the various blood safety sexual risk behaviours among blood donors from East Croatia and the possibilities for improving the present blood donor screening procedure.

Materials and methods

The study included 423 blood donors of both sexes who completed a specially designed anonymous questionnaire immediately after their blood donations. The questionnaire contained questions on demographic data, sexual preferences, and possible sexual risk behaviours in the period before the blood donation.

Results

The study revealed that the most common forms of sexual risk behaviour among Croatian blood donors had been irregular condom use during sexual contacts with new partners (294/423; 69.5%) and five or more sexual partners during the lifetime (213/423; 50.4%). More male than female subjects had had five or more sexual partners during their lifetime (p<0.0001). Compared to married donors, single subjects more frequently reported sexual contacts without using a condom with their new partners in the period from the last blood donation (p<0.0001) and also in the period of 1 month before current blood donation (p=0.0060). A larger number of younger than older subjects had practiced different types of sexual intercourses during the lifetime (p=0.0002) but more older than younger subjects reported irregular use of condom on sexual contacts with a new partner during their lifetime (p=0.0231).

Conclusion

Blood donors who were involved in various forms of sexual risk behaviour represent a serious threat to the health of blood recipients. In this respect a new approach to blood donor screening procedure with additional questions on sexual behaviour in anonymous donor questionnaires would improve the safety of transfusion treatment in East Croatia.     

HemoCue photometer: a better alternative of hemoglobin estimation in blood donors?

Purpose of study

To find out the prevalence of anemia in potential blood donors and to compare the direct cynmethemoglobin and HemoCue methods for assessing hemoglobin concentration.

Material and methods

The study group included 540 potential blood donors; who were tested for their hemoglobin concentration in capillary blood samples by direct cynmethemoglobin and HemoCue methods.

Results

Average age of the potential donors was 39.2 year, with 505 males and 35 females. Mean hemoglobin concentration using the HemoCue was 13.2 ± 2.4 g/dl and 12.8 ± 2.3 g/dl with the direct cynmethemoglobin method (Table 1). The prevalence of anemia was slightly higher when using the direct cynmethemoglobin method (14.1%) as compared to HemoCue method (13.6%). The sensitivity and specificity for the HemoCue assessment was 94.1% and 95.2% respectively as compared to 90.1% and 94.2% respectively for the direct cynmethemoglobin method.

Conclusion

Photometric hemoglobin determination (HemoCue) combines the convenience of onsite testing with sufficient accuracy and rapidity. We feel this is a better method for evaluating potential blood donors.     

Epidemiology of human immunodeficiency virus infection in blood donations in Europe and Italy

Background

The safety of blood with regards to transmission of infectious diseases is guaranteed by European laws that regulate both the selection of donors through pre-donation questionnaires and serological screening. However, variability in the epidemiology of human immunodeficiency virus (HIV) infection in different countries and some differences in the selection of donors can influence the efficacy (with regards to the safety of blood) of these processes. In this study we compared the prevalence of HIV in blood donations in the three macro-areas of Europe and in various western European countries, analysed the criteria of selection and rewarding of donors in western European countries, and studied the trend in the prevalence of HIV in Italy from to 1995 and 2006.

Methods

European data were derived from the European Centre for the Surveillance of HIV; Italian data were obtained from the Transfusion-Transmitted Infections Surveillance System and National and Regional Register of blood and plasma. The information on eligibility criteria and rewarding offered to donors was derived from international sources.

Results

The prevalence of HIV in blood donations was highest in eastern Europe, followed by central Europe and western Europe. Among the western European countries, Spain, Italy and Israel had the highest prevalences; the prevalence was noted to be higher in countries which did not offer any rewarding to the donor. In Italy the prevalence of HIV was 3.8 cases per 100,000 donations in 2006 and increased between 1995 and 2006, both among donations from repeat donors and first time donors.

Conclusions

The data highlight the need to continue improving the selection of donors and the coverage of the surveillance systems for HIV infection in transfusion services.     

Screening of related donors and peripheral blood stem cell collection practices at different Italian apheresis centres

Background

Recommendations on eligibility criteria for donation of haematopoietic stem cells, management of collection of the cells and follow-up mainly concern unrelated donors. The aim of this study was to analyse the screening of related donors and collection practices at different Italian apheresis centres.

Materials and methods.

A questionnaire regarding eligibility criteria for related haematopoietic stem cell donors, their peripheral blood collections and early follow-up was sent to several apheresis units. Data from the full charts of 500 candidates, screened between May 2005 and December 2009, were retrospectively evaluated.

Results

The donors’ records, eligibility criteria, collections and follow-up are managed differently in each centre. Of the 500 evaluable candidates (51.2% male, 49.8% female; median age 47 years, range 13–77), 26.4% underwent thorough screening according to Italian Bone Marrow Donor Registry standards, while local protocols were applied to 73.6%; 91 candidates (18.2%) proved ineligible for donation. In the end, 352 donors (53.4% male, 46.6% female; median age 45 years, range 16–76) underwent 508 leukaphereses. Central venous catheters were used in 8.0% of donors, mainly in one centre. Unsuitable pre-apheresis peripheral blood parameters were reported in 38.7% of the aphereses. Leukapheresis-related adverse events were recorded in 23.0% of the procedures, with a drop-out rate of 0.2% for severe events. No donation-related fatalities occurred. The CD34+ cell yield was <2×10⁶/kg of recipient’s body weight from 1.1% of donors ≥70 years old.

Discussion.

More uniformity in donor screening procedures, management of peripheral blood collection and follow-up should be planned at a national level to maximise the safety of related donors.