Optimal blood grouping and antibody screening for safe transfusion.

(Full text is available at http://www.manu.edu.mk/prilozi). Introduction. Blood group antigens as integrated parts of the red cell membrane have many essential functions for the cell as well as for the organism, but they are recognized as unique antigens for the purpose of safe blood transfusion. Especially in the case of those with great clinical importance because of their involvement in haemolytic transfusion reactions and hemolytic disease of the newborn, it is very important that they be correctly, and some of them routinely, typed in blood donors as well as in patients. Aim. Evaluation of Rh and Kell blood group antigen frequencies in blood donors as well as the incidence of alloimmunization in transfused patients in the Macedonian population. The need for routine typing of certain blood group antigens in addition to ABO and RhD was also evaluated. Material and method. We evaluated data from 1600 ABO/Rh and Kell typed blood donors (from January 2003 to May 2008), as well as the data from pretransfusion testing (ABO/RhD blood typing, irregular red blood cell antibody screening and compatibility testing) and antibody identification in the period from January 2005 to November 2008. All tests were performed by the DiaMed micro tube gel system. Results. The frequencies of ABO antigens were as follows: A (39.7%), O (38%), B (14.1%), AB (7.4%). The frequencies of Rh antigens were as follows: D pos. (84.2%), D neg. (15.8%), C (58.3%), c (82.4%), E (21.3%), e (97.1%). We found the following frequencies of Kell phenotypes: K+ k- (0.25%), K+ k+ (6.18%), and K- k+ (93.6%) with the total frequency of K antigen of 6.4%. Antibody screening and/or cross-match were positive in the sera from 150 transfused patients. In 75 (50%) sera the following 81 antibodies were identified: anti-K (26), -E (25), -e (1), -C (4), -c (6), -C(w) (2), -k (1), -Fy (a) (3), -Fy(b) (1), -Jk(a) (3), -Lu(b) (1), -Le(b) (2), -Le(a) (1), -M (4), -P1 (1). The most frequent alloantibody was anti-K with 32%, and anti-E with 30.8% of all identified antibodies. Conclusion. Alloimmunization to red cell antigens is still a current problem in our transfusion practice. It is obvious that the additional testing of blood donors for Rh and Kell antigens should be implemented as a routine to prevent as far as possible the incidence of alloimmunization. It would also be cost-effective, bearing in mind the additional laboratory testing necessary to provide compatible blood for alloimmunized patients. Extended blood typing should be implemented for some categories of polytransfused patients as well. This strategy is another step forward to improve the safety of blood transfusion with optimal blood grouping. Key words: Kell phenotypes frequency, alloimmunization, blood grouping, safe transfusion.

[The role of the von Willebrand factor in renal diseases and haemodialysis patients]. / Bioloskata aktivnost na fon Vilebranodoviot faktor kaj bubrezni i hemodijalizni bolni.

During a period of twenty years, the von Willebrand factor (VWf) biological activity was evaluated in 805 patients with vein thrombosis, diabetes mellitus, chronic renal failure and ischemic heart disease. The examined patients were 168 with vein thrombosis, 129 with diabetes mellitus, 412 with chronic renal failure (CRF), and 96 with ischemic heart disease. The biological activity was also determined in 104 haemodialysis patients using four different haemodialytic membranes: 30 on cuprophan membrane, 30 on polymethylmetacrylate membrane (PMMA), 24 on hemophane and 20 patients on polysulphone (PS) membrane. In 42 patients with arterio-venous fistula prone to thrombosis, the biological activity of the von Willebrand Factor was 178% in comparison to 106% in the control group. The biological activity of VWF was increased in patients with vein thrombosis (p < 0.02), in patients with diabetes mellitus (p < 0.01), CRF (p < 0.05), and in patients with ischemic heart disease (p < 0.01). The highest biological activity was found in patients on PMMA (p < 0.001), then cuprophan (p < 0.05) and hemophane membrane (p < 0.01), while the lowest increase of its concentration was noticed in patients on PS without statistical significance. In arteriovenous fistula prone to thrombosis patients biological activity of the von Willebrand Factor was significantly increased (p < 0.01). Our investigations show the importance of VWF as a marker of endothelial disfunction, a possible predictor of A-V fistula thrombosis, and a possible marker of haemodialysis membranes biocompatibility.

[Clinical and pathohistological characteristics of aplastic anemia]. / Klinicke i pathohistoloske karakteristike aplasticne anemije

Clinical symptomatology, pathohystiological characteris of bone marrow and the effects of treatment achieved in 21 patients with aplastic anaemia (a.a.) have been presented in this paper. Compared to one of our previous analised serie the number of patients with a.a. of both sexes and age has doubled for the last few years. The ethiogenesis in 14 cases was of unknown origin. In tree cases chloramphenicol was a cause, paroxysmal nocturnal haemoglobinuria in three other cases and one appeared in pregnancy. Pathohystiology of bone marrow has in 7 cases acellular in 11 hypocellular and in tree partial hypercellular appearance. Immunohaematological examinations yielded positive antiglobuline tests in tree cases (out of 17 examined) and positive thrombocytic antibodies in 2 patients out of 14. Australia antigen has been found positive in 3 patients (out of 18), Au antibodies in one out of nine patients, while three developed manifest serum hepatitis duing the causee of treatment. Tree patients whose final diagnosis was paroxysmal nocturnal haemoglobinuria previosly were diagnosed and treted as a.a., while two with a.a. gave positive acid and sugar tests for that syndroma. The treatment in this seria of a.a. was by corticosteroids, testosteron. There has not been any significant impruvement in prolonging the patients lives in this seria comparing the previous one in which there had been given no anabolic hormones. Most of the patients (more than 50%) did not survive more than 24 months.