Irena Jukić

International survey on NAT testing of blood donations: expanding implementation and yield from 1999 to 2009

International survey on NAT testing of blood donations : expanding implementation and yield from 1999 to 2009.

Plasma cytokines as markers of aseptic prosthesis loosening

The proinflammatory cytokines IL-1β, IL-8, and TNF-α play a major role in the process of bone resorption during aseptic loosening of large joint prostheses. These cytokines secreted locally during bone resorption in aseptic loosening may enter peripheral circulation. Increased concentration of IL-1β, IL-8, and TNF-α in peripheral circulation may indicate aseptic loosening. We determined whether bone resorption could be verified by cytokine presence in plasma. We recruited 50 patients with aseptic prosthesis loosening, 50 with stable prostheses, 50 with osteoarthritis, and 50 healthy individuals. Cytokine levels were determined in plasma by ELISA tests. Patients with prosthesis loosening had higher plasma levels (IL-1β, 3.7 ± 5.5 pg/mL; IL-8, 14.7 ± 9 pg/mL; TNF-α, 32.7 ± 32.4 pg/mL) than patients with stable prostheses (IL-1β, 1.5 ± 2 pg/mL; IL-8, 8.1 ± 4.7 pg/mL; TNF-α,22.9 ± 18.7 pg/mL), patients with osteoarthritis (IL-1β,0.7 ± 1.1 pg/mL; IL-8, 5.8 ± 3.8 pg/mL; TNF-α, 9.8 ± 7.7 pg/mL) and healthy individuals (IL-1β, 0.7 ± 1.1 pg/mL; IL-8, 4.2 ± 1.3 pg/mL; TNF-α, 3.9 ± 3.9 pg/mL). Our data suggest elevated plasma levels of proinflammatory cytokines may be useful as markers of bone resorption in the laboratory diagnosis of prosthesis loosening.Level of Evidence: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Distribution of weak D types in the Croatian population

Dear Sir, The Rh blood group system is determined by the highly homologous RHD and RHCE genes located on the first chromosome, which encode for the RhD and RhCE polypeptides. D antigen is of special clinical relevance in the fields of transfusion medicine and obstetrics. Owing to its high immunogenicity, D antigen can induce the production of alloantibodies and thus cause posttransfusion haemolytic reaction and haemolytic disease of the newborn (Wagner et al., 2000). About 0·2–1% of the European population are carriers of structurally altered RHD alleles encoding for various types of weak D proteins. At the molecular level, point mutations resulting in amino acid substitutions in the intracellular or transmembranous segments of RhD protein are causing weak D phenotypes. More than 170 different RHD alleles closely related to the expression of the respective D phenotype, including more than 70 weak D types, have been discovered to date (Flegel, 2007). Some weak D types (types 1, 2 and 3) are not associated with the development of alloantibodies; however, alloimmunisation in weak D types 4·2, 11 and 15 carriers have been reported (Flegel, 2006). Owing to the extremely small phenotypic variation, particular weak D types are very difficult to differentiate by serology and can only be identified by molecular methods, thus enabling definitive decision on the mode of transfusion treatment and the need of anti-D prophylaxis in pregnant women. The individuals who are carriers of weak D types 1, 2 and 3 can receive transfusion of D+ red blood cell (RBC) units, although such pregnant women do not require anti-D prophylaxis. Thus, the unnecessary utilisation of D− RBC units and RhIg is avoided (Flegel and Wagner, 2002). Particular segments of the RHD gene sequence are multiplied by RHD genotyping using primers specific for the known mutations characterising particular weak D types by use of the polymerase chain reaction with sequence-specific priming (PCR-SSP). This procedure is employed to determine polymorphism of the weak D types.

Blood collection staff education in the prevention of venepuncture failures and donor adverse reactions: from inexperienced to skilful staff.

Dear Sir, Blood collection is the first link of the transfusion chain, which is of utmost importance for the quality and safety of transfusion treatment, as well as for donor satisfaction. Venepuncture failures and adverse reactions not only reduce the precious blood supplies available for transfusion treatment, but also discourage future donations1,2. Thus, each blood-collecting establishment should continuously invest efforts to keep the rate of venepuncture failures and donor adverse reactions as low as possible. These goals can be achieved by careful staff education along with ensuring due quality of this segment of the transfusion service. This primarily means monitoring venepuncture failures and donor reactions by using appropriate quality indicators and implementing relevant corrective measures based on the results obtained. While the frequency of venepuncture failures depends heavily on the skill of the blood collection staff, vasovagal reactions are consequential to an array of haemodynamic and psychological changes occurring in the donor during and after blood donation. It should be appreciated that these reactions are frequently underlain by stress, response to pain, fear and discomfort. The blood collection staff should, therefore, invest efforts to create a pleasant, relaxing environment and to distract the donor’s attention from the unpleasant aspects of blood donation, thus reducing the prevalence of these reactions3. At the Croatian Institute of Transfusion Medicine (CITM), a quality management system was implemented as early as 1997 and certified in 2001. At the very beginning of its implementation, collection failures were identified as one of the leading types of nonconformities4. At the CITM, collection failures have been defined as failed needle insertion into the vein, and any blood collection interruption due to prolonged duration or other factors related to venepuncture technique (haematoma, poor/absent blood flow) or donor vasovagal reaction. Venepuncture and blood collection successfully performed at a second attempt with the donor’s consent is not classified as collection failure at the CITM. The rate of thus defined collection failures was 1.47% in 1998 and declined continuously to 0.5% in 2001 as a result of proper staff education5. During the 2002–2013 period, the incidence of collection failures varied from 0.52 to 0.92%. The factors influencing the occurrence of collection failures were analysed on several occasions during the study period and it was found that experience of the staff performing venepuncture was of great importance. Over the years there was a tendency to frequent staff turnover in the blood collection and consequently a variable rate of collection failures. Although staff education that includes acquiring necessary skills has always been perceived as a precondition for quality performance, data on the time needed for newly employed workers to acquire the necessary experience are almost completely lacking. The aspect of adopting communication skills that provide the donor or patient with the feeling of safety and confidence is even less explored3. In an attempt to determine the time needed for education, training and supervised performance of blood collection, we compared the rate of venepuncture failures (including successful repeat venepunctures) and early vasovagal donor reactions during and after whole blood collection between the procedures performed by experienced (n=3) and less experienced (n=8) staff members. All donation non-conformities known or suspected to be caused by venepuncture technique were considered as “venepuncture failures”. For newly employed workers, the two types of events were monitored during an 18-month period from their starting to perform venepuncture (usually within 15–30 days of their starting to work in the blood collection department) and the incidence of events was compared with that recorded for experienced staff members. In this study, experienced staff members were those with 3 years of experience in blood collection. The mean number of venepuncture failures and donor vasovagal reactions at blood collection performed by these experienced staff members during an 8-month monitoring period served as a reference value. Monitoring of the performance of the experienced staff members began after 3 years of their work in the blood collection department. The data presented refer to 73,332 donations, comprising 11,061 and 62,271 donations collected by experienced and less experienced staff members, respectively. For experienced staff members, the mean incidence of venepuncture failures during the 8-month monitoring period was 0.81%, while that of early donor vasovagal reactions was 1.08%. The incidence of venepuncture failures and donor reactions at blood collection performed by less experienced workers according to the length of their work experience is shown in Figures 1 and ​and2.2. Considering the relatively low frequency of the events observed and a longer period of monitoring, we decided to compare 3-month periods in order to get a statistically relevant pattern and to avoid accidental variations that may result from analysis of short periods. Figure 1 Incidence of venepuncture failures due to venepuncture technique at blood collection performed by newly employed workers during an 18-month period. Figure 2 Incidence of donor vasovagal reactions at blood collection performed by newly employed workers during an 18-month period. The difference in proportions test yielded a statistically significant difference in the rate of venepuncture failures between the experienced and less experienced workers in the first two periods analysed (months 1–3, p=0.002; months 4–6 p=0.041). Detailed analysis according to months revealed that the statistical significance between the results of the experienced and less experienced workers disappeared in month 5 of work in the blood collection department (p=0.087). In fact, the incidence of venepuncture failures continued to be higher for the less experienced workers until the end of the first year of work. Statistical analysis did not confirm significant differences in the incidence of donor vasovagal reactions between the experienced and less experienced workers; however, the mean incidences recorded per 3-month period showed that the incidence of donor reactions was higher for inexperienced workers throughout the first year of their work than for the control group of experienced staff. Overall data suggest that the optimal initial education of staff members performing blood collection should last 5–6 months, while taking into account that up to 1 year is needed to acquire desired skill and experience. A limitation of the present study was the relatively small number of subjects and almost impossible long-term monitoring of their work due to the high turnover of workers engaged in blood collection. It may be useful to conduct similar investigations in other establishments to enable comparison of results with ours. These data are highly relevant for planning and monitoring the education and training of newly employed workers performing blood collection.

Bacterial contamination of blood products at the Croatian Institute of Transfusion Medicine: results of eleven-year monitoring

The aim of this study is to present the results and experiences of the Croatian Institute of Transfusion Medicine (CITM) in blood product testing for the presence of bacterial contamination. This is the first study analysing the results of bacterial testing of blood products in Croatia.

Combined cell index in assessing blood donor iron stores

The aim of this study was to assess the appropriateness of using combined cell index (CCI) in the assessment of iron stores in blood donors. This index is calculated by the formula: red blood cell distribution width (RDW) × 104 × mean corpuscular volume (MCV)−1 × mean corpuscular haemoglobin (MCH)−1.

Alloimmune Neonatal Neutropenia in Croatia during the 1998–2008 Period

The aim of this study was to estimate the incidence of the disease and to analyze laboratory data of 23 newborns undergoing serologic testing for alloimmune neonatal neutropenia (ANN) during the 1998–2008 period in Croatia.

Quality control of leucocyte‐depleted platelet concentrates obtained by buffy‐coat method

Quality control results on leukoreduced buffy‐coat platelet pools during the 7‐year period (2005–2011) are presented with the aim to assess their overall quality and trends recorded during the study period.

Three-Year Experience in NAT Screening of Blood Donors for Transfusion Transmitted Viruses in Croatia

Background: Croatia implemented individual donation (ID)-NAT testing of blood donors in 2013 for three viruses HBV, HCV, and HIV-1 as a mandatory test for all blood donors. This study assessed the impact of NAT screening 3 years after its implementation. Methods: A total of 545,463 donations were collected and screened for HBV, HCV, and HIV-1 using the Procleix Ultrio Plus Assay. All initially reactive (IR) NAT samples were retested in triplicate and, if repeatedly reactive (RR), NAT discriminatory assay (dNAT) was performed. ID-NAT positive donations were confirmed by RT-PCR on the COBAS AmpliPrep/TaqMan platform. Results: Out of 545,463 samples tested, 108 (0.02%) were RR in NAT. There were 82 (75,9%) HBV reactive, 16 (14.8%) HCV reactive, and 10 (9.3%) HIV-1 reactive samples. 51 (47.2%) samples were ID-NAT positive only. Out of these 51 NAT yield cases, 1 window period HIV-1 and 50 occult HBV infections (OBI) were determined. There were only two potential HBV DNA transmissions from OBI donors. Conclusion: The implementation of NAT screening for three viruses has improved blood safety in Croatia. During the 3-year period, 1 window period HIV-1 and a number of occult HBV donations were identified.

Polymorphism 4G/5G of the plasminogen activator inhibitor 1 gene as a risk factor for the development of allergic rhinitis symptoms in patients with asthma

Plasminogen activator inhibitor-1 (PAI-1) is a glycoprotein which has a role in tissue remodelling after inflammatory processes. The objective is to investigate the frequency of PAI-1 gene polymorphism (4G/5G) in patients with a lung ventilation dysfunction in asthma and allergic rhinitis. Genomic DNA was isolated and genotypes of polymorphism of PAI-1 4G/5G and ABO were determined using the methods of RT-PCR and PCR-SSP. Study group includes 145 adult patients diagnosed with chronic asthma, with all clinically relevant parameters and the laboratory markers of pO2, IgE and eosinophils in sputum and nasal swab. In the processing of data, appropriate statistical tests (Kolmogorov–Smirnov test, median, interquartile ranges, χ2 and Mann–Whitney U tests) were used. Patients with symptoms of allergic rhinitis were significantly younger and had an almost four time higher levels of IgE (P = 0.001), higher pO2 (P = 0.002) and PEF (P = 0.036), compared to those who do not have these symptoms. Genotype PAI 4G/4G is significantly more common in patients with allergic rhinitis (28.1% vs. 16.1%; P = 0.017) compared to the genotype 5G/5G. Carriers of the genotype 4G/5G also have a borderline statistical significance. There were no statistically significant difference in the incidence of allergic rhinitis in the carriers of any ABO genotypes. The frequency of PAI genotype 4G/4G is significantly more common in patients with allergic rhinitis. The results suggest that the carriers of at least one 4G allele are at a higher risk for developing symptoms of allergic rhinitis in asthma.