BACKGROUND:The objective was to determine the frequency of occurrence of alloantibodies among pregnant women in Iran. STUDY DESIGN AND METHODS:This was a prospective cross-sectional study, which was carried out in the immunohematology reference laboratory of the Iranian Blood Transfusion Organization in Tehran, Iran, in 2008 to 2015. Screening and identification of red blood cell (RBC) alloantibodies was done on the sera of 7340 pregnant females using the standard tube method and gel column agglutination technique. RESULTS:Alloantibodies were identified in the serum of 332 of the 7340 (4.5%) pregnant women. A total of 410 antibodies were detected in 332 positive maternal serum samples with no previous history of blood transfusion. Anti-D was the most common antibody accounting for 70.5% of all the antibodies formed in D-women. The incidence of specific alloimmunization other than Rh group was 14.4%. CONCLUSION:We concluded that the alloimmunization rate was high in comparison with wide pattern in previous studies. In Iran, like other developing countries, alloimmunization screening tests are performed only to detect anti-D in pregnant D-women. This high rate of alloimmunization, quite possibly, is due to the fact that the majority of blood samples came from pregnant women known to have previous obstetric problems. However, we suggest that RBC antibody screening tests should be extended to all D1 women.ABBREVIATIONS: HDFN 5 hemolytic disease of the fetus and newborn; IBTO 5 Iranian Blood Transfusion Organization.From the

<b>Background:</b> The lack of correct blood grouping practices can lead to missing of the rare Bombay Oh phenotype and subjecting patients to the risk of severe hemolytic transfusion reaction. In the absence of blood donor registry, transfusion management of patients is a challenge. We performed this study in order to estimate the prevalence of the Bombay blood group (Oh) in Iran and to determine whether consanguinity plays a role in the prevalence of Oh group. <b>Methods:</b> This is a descriptive study in the Immunohematology Reference Laboratory of the Iranian Blood Transfusion Organization (IBTO) Tehran, Iran, over a period of 7 years. All donor blood samples showing blood group O and a strong initial reaction with blood group O RBC control cells were tested with anti-H lectin. Also blood samples from blood group O patients were tested with anti-H lectin if all cells on both antibody screening tests and antibody identification panels were reactive with negative auto control test. Specialized tests like adsorption/elution technique and inhibition assay for determination of secretor status were performed on Oh cases. Any history of consanguineous marriages were recorded. All variables were categorical variables, and percentage and proportions were calculated manually. <b>Results:</b> Analysis of the results of over 7 million first-time blood donors in Iran showed that the most common ABO blood group was O, with 2,520,000 (36%) subjects. 56 Oh individuals' (donors and patients) phenotypes (0.0008%) were detected. Consanguinity was observed in 50 cases (89%). <b>Conclusions:</b> This study shows that the prevalence of Bombay blood group in the general population of Iran is relatively high (0.0008%) and associated with consanguineous marriage. Thus, consanguinity is still an important risk factor present.

We report the first study of antigen and phenotype prevalence within various blood group systems in the Iranian general population. In this retrospective study, samples from 3475 individuals referred to the Immunohematology Reference Laboratory of the Iranian Blood Transfusion Organization, Tehran, Iran, for paternity testing from 1998 to 2008 were additionally tested for red blood cell (RBC) antigens in the Rh, Kell, Kidd, Duffy, MNS, Lutheran, P1PK, and Xg blood group systems. The antigen testing was performed by the tube method, and the phenotype prevalences were expressed as percentages. Of 3475 (1857 male and 1618 female) blood samples, 1268 samples were typed as group O (36.49%), 1115 as group A (32.09%), 823 as group B (23.68%), and 269 as group AB (7.74%). In our sample population, 3152 (90.71%) samples were D+ and 323 (9.29%) were D-. Analysis of Rh antigen typing results showed e (3359; 96.66%) to be most prevalent in the Iranian population, followed by D (3152; 90.71%), C (2677; 77.04%), c (2557; 73.58%), and E (1059; 30.47%). In the Kell blood group system, 3293 (94.76%) samples were typed as K-k+. For the Kidd and Duffy blood group systems, the following were the most common phenotypes: Jk(a+b+) (1703; 49%), Jk(a+b-) (1006; 28.95%), Fy(a+b+) (1495; 43.02%), and Fy(a+b-) (1005; 28.92%). In the MNS blood group system, the following were the most common phenotypes: M+N+ (1668; 48%), M+N-(1310; 37.70%), S+s+ (1564; 45%), and S-s+ (1392; 40.06%). In the Lutheran and P1PK blood group systems, Lu(a-b+) and P1+ phenotypes were observed in 3292 (94.73%) and 1966 (56.58%) samples, respectively. The Xg antigen was present in 1953 (56.20%) samples versus 1522 (43.80%) samples identified as Xg(a-). Knowledge of the prevalence of RBC antigen phenotypes in a population can be useful in databank creation for providing antigen-negative compatible blood to patients with multiple alloantibodies. Immunohematology 2016;32: 135-139.

Abstract. The uniformly minimum variance unbiased (UMVU), maximum likelihood, percentile (PC), least squares (LS) and weighted least squares (WLS) estimators of the probability density function (pdf) and cumulative distribution function are derived for the generalized Rayleigh distribution. This model can be used quite effectively in modelling strength data and also modelling general lifetime data. It has been shown that MLE is better than UMVUE and UMVUE is better than the others. An application to waiting times (min) of 100 bank customers.

Background and Objectives In transfusion medicine, it may be a challenge to acquire compatible blood for patients who have clinically important alloantibodies to high-prevalence antigens. The aim of this study was to study prevalence of rare D--phenotype in samples from patients and their relatives referred to the Immunohematology reference laboratory of the Iranian Blood Transfusion Organization and the detection and identification of the phenotype and associated antibodies, particularly in an antenatal setting. This is the first report of the cases evaluated by the IBTO and family studies of the D--proposita in Iran and possibly the first attempted comprehensive study in the current transfusion-related literatures. Materials and MethodsThis retrospective cross-sectional study was carried out on 6720 pregnant women and individuals with difficult positive pretransfusion testing referred for ABO/Rh(D) typing and antibody screening during a period of 8 years from 2008 to December 2016 in the Immunohematology Reference Laboratory of the Iranian Blood Transfusion Organization, Tehran, Iran.Results During 2008 to December 2016, 16 persons from ten families were detected to have rare D--phenotype. Anti-Rh17 and anti-c were identified in plasma of the 11 persons, including 10 females with a history of multiple unsuccessful pregnancy and the total number of 24 abortions and one male with history of blood transfusion vs. 5 individuals, including an unmarried single woman, 1 person with a history of first-time pregnancy and 3 persons with a history of multiple pregnancy, who showed no alloimmunization. Based on these collective findings, we interpreted these results as being confirmed as D--phenotype (0.23%).Conclusion Irrespective of Rh (D) group a serological antibody screening test is recommended to be required in a National prenatal testing guideline.Key words: Anti-Rh17 (anti-Hro), D--phenotype, haemolytic disease of the fetus and newborn.

This article reviews information on the clinical significance of antibodies to antigens in the Raph, John Milton Hagen, I, Globoside, Gill, Rh-associated glycoprotein, FORS, JR, LAN, Vel, CD59, and Augustine blood group systems. Antibodies to many of the antigens in these groups are rarely encountered because of the high prevalence of the associated antigens in most populations. For many of these antibodies, the clinical significance-that is, the potential to cause reduced survival of transfused antigenpositive red blood cells or a transfusion reaction (e.g., anti-P, anti-Jr a , and anti-Lan), and/or hemolytic disease of the fetus and newborn (e.g., anti-RHAG4 and anti-Vel)-has been documented. For other antibodies, their prevalence is so rare that information on the clinical significance of their antibodies is not available (e.g., anti-FORS1). Immunohematology 2018;34:85-90.

Hyperhemolysis syndrome (HS) is a delayed type of transfusion reactions (DTHRs). These may occur in patients with hemoglobinopathies due to destruction of red blood cells (RBCs). A 17-year-old boy with B-thalassemia and a history of multiple transfusions, after several RBCs transfusions developed hemolysis and hemoglobinuria with a decreased hemoglobin (Hb) level in the absence of bleeding that continued with splenomegaly. The antibody screen test (LISS AHG) and direct anti-globulin test (DAT) were performed. An 11-cell antibody identification panel (IBTO home-made) was used. Acid elution procedure was done using a commercial kit. The patient RBC phenotyping was attempted by treating the cells, following a chloroquine treatment procedure. Laboratory findings showed that his blood group was "A" Rh positive. His RBC phenotyping was negative for Jka antigen. The LISS antibody screening test result was negative with a weakly positive auto control result but DAT was positive for both C3d and IgG. The antibody identification test showed the presence of anti-Jka alloantibody and also anti-Jka was identified with eluate reacting stronger with homozygous cells (Jka+Jka+). The patient received steroid and IVIG as the main treatment and followed by receiving compatible blood units but hemolysis was not resolved and his Hb level was not increased, finally he was splenectomized. The patient's Hb level and clinical symptoms improved after the splenectomy, showing that the spleen may have a role in the destruction of the recipient and the donor blood cells.

Alloimmunization against the Rhesus-D (RhD) antigen still remains as a major cause of hemolytic disease of fetus and newborn (HDFN). Determination of paternal RhDzygosity is performed by molecular testing and is valuable for the management of alloimmunized pregnant women. A 30-year-old pregnant woman with AB negative blood group presented with two consecutive abortions and no history of blood transfusion. By application of the antibody screening, identification panel, and selected cells, she was found to be highly alloimmunized. RhDzygosity was performed on her partner and was shown to be homozygous for RhD. The sequence- specific priming-polymerase chain reaction used in this report is essential to establish whether the mother requires an appropriate immunoprophylaxis or the fetus is at risk of HDFN.