Clinical and Laboratory Diagnosis of Antiphospholipid Syndrome: A Review.

The antiphospholipid syndrome (APS) manifests through venous or arterial thrombosis, with or without pregnancy complication alongside the continuous presence of antiphospholipid antibodies (aPL). APS classification relies on three aPL subtypes: anticardiolipin (aCL), anti-ß2-glycoprotein I antibodies (anti-ß2GPI), and lupus anticoagulants (LA) antibodies. Given that thrombosis and pregnancy issues are not unique to APS, the precise and reliable identification of aPL forms the basis for diagnosis. Semi-quantitative solid-phase assays identify two antibodies, aCL and anti-ß2GPI, while LA detection occurs through various phospholipid-dependent coagulation assays that are based on antibody behaviour. LA, specifically, is conclusively associated with thrombosis, prompting discussions around the serological criteria for APS. Despite advancements in LA detection, the standardisation of all aPL detection assays remains imperative. The combined presence of aCL and anti-ß2GPI with thrombosis inconsistently triggers concern. Initial presentations by APS patients commonly exhibit a heightened risk of stroke, miscarriages in the later stages of pregnancy, positive results of LA tests, and widespread thrombosis across multiple organs, often leading to adverse outcomes. Correctly diagnosing this condition is pivotal to avoid unnecessary long-term secondary thromboprophylaxis.

Red Blood Cell Alloimmunization in Pregnancy: A Review of the Pathophysiology, Prevalence, and Risk Factors.

This review paper provides an overview of the risk factors and laboratory testing for red blood cell (RBC) alloimmunization in pregnancy. RBC alloimmunization is a significant medical issue that can cause haemolytic disease of the fetus and newborn (HDFN), leading to neonatal morbidity and mortality. Current HDFN prophylaxis targets only Rhesus D (RhD) alloimmunization, with no effective measures to prevent alloimmunization to other RBC antigen groups. Several factors can increase the risk of developing RBC alloimmunization during pregnancy, including fetomaternal haemorrhage, RBC and maternal genetic status, and previous transfusions. Identifying these risk factors is essential to execute the appropriate management strategies to minimize the risk of HDFN. The review also discusses the laboratory methods and overview of pregnancy management. The paper highlights the importance of identifying and managing the risk factors for RBC alloimmunization in pregnancy to minimize the risk of HDFN and improve neonatal outcomes.

Hematological Profile of Hb Adana Among High School Students in Northeast Peninsular Malaysia.

Background Hb Adana is a non-deletional alpha (α)-thalassaemia variant resulting from mutations in α1- or α2-globin codon 59 (αCD59), leading to the production of unstable α-globin. Clinical manifestations can vary from silent carrier status to dependence on blood transfusions, hepatosplenomegaly, skeletal deformities, and spinal cord compression. Despite the significance of Hb Adana inheritance, studying this variant poses challenges due to the scarcity of molecular tests and the potential for routine diagnoses to be overlooked. This study aims to investigate the prevalence of Hb Adana among local high school students and assess the hematological parameters and hemoglobin analysis of Hb Adana in Malaysia. Methodology This retrospective study analyzed 13,721 blood samples collected from high school students participating in Malaysia's National Thalassaemia Screening Program at Hospital Raja Perempuan Zainab II (HRPZ II). Deletional α-thalassaemia was detected using multiplex gap-polymerase chain reaction (PCR), while common non-deletional α-thalassaemia was identified using multiplex amplification refractory mutation system (ARMS) PCR. Data were extracted from the HRPZ II database for analysis. Results Among the participants, 2327 individuals were found to have either common deletional (n=1037, 44.6%) or non-deletional (n=1290, 55.4%) α-thalassaemia. Hb Constant Spring was the most prevalent non-deletional α-thalassaemia, accounting for 53.03% of cases. Thirty-one participants (1.33%) exhibited αCD59α/αα, and one (0.04%) had αCD59α/-α3.7. Among the 32 subjects with Hb Adana, 87.5% were Malay, and 12.5% were Orang Asli. Additionally, seven cases of HbE/Hb Adana co-inheritance were identified. Hemoglobin levels in heterozygous Hb Adana individuals ranged from mild anemia to normal, between 95 g/L and 153 g/L. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were approximately 73 fL and 23 pg, respectively. Conclusion This study delineates the distribution of α-thalassaemia mutation patterns among high school students in Kelantan, Northeast Peninsular Malaysia. Our findings indicate that Hb Adana is rare in our region and co-inheritance with an α-gene deletion results in α+-thalassaemia and with HbE, α0-thalassaemia. All heterozygous Hb Adana individuals exhibited low MCVs and MCHs.

Anti-D Alloimmunization Following Rhesus-Incompatible Platelet Transfusion in a Myelodysplastic Syndrome Patient.

Patients with myelodysplastic syndrome (MDS) often need platelet transfusions to address thrombocytopenia. The risk of alloimmunization, particularly in Rhesus (Rh) incompatibility between donors and recipients during platelet transfusions, is heightened, especially with whole blood-derived pooled platelets as opposed to apheresis platelets. Although the occurrence of alloimmunization from platelet transfusions is minimal, there is an ongoing debate about whether Rh immune globulin (RhIg) should be administered to Rhesus D (RhD)-negative recipients of RhD-positive platelet units. We present a unique case of anti-D alloimmunization in a 56-year-old patient with underlying MDS following multiple platelet transfusions but never received packed cell transfusion or anti-D immunoglobulin. Some studies advocate for RhIg administration in specific scenarios and for certain patient populations. This case underscores the importance of considering Rhesus compatibility or administering anti-D immunoglobulin in cases where frequent platelet transfusions are required.

The Blood Donor Deferral Rate and the Reasons for Deferral at a Tertiary Care Teaching Institute in Northeastern Malaysia.

A deferral takes place when donors fail to meet the eligibility criteria for donating blood during their visit to a blood collection site. Deferral periods, which can be either permanent or temporary, are implemented to protect the well-being of both the donor and the recipient. This study aimed to investigate the frequency of deferrals and the various factors contributing to them. A retrospective analysis was conducted at the Transfusion Medicine Unit of Hospital Universiti Sains Malaysia (USM), utilizing data obtained from blood donors during the period from January 2022 to June 2023. The research included a cohort of 18,751 donors who visited our transfusion unit for blood donation. Data, including gender, age, and reasons for deferral, were collected by reviewing the records of donors who were deferred. Descriptive statistics were employed to analyze the data of deferral blood donors. Out of 18,751 blood donors, 3,533 (18.84%) were deferred, consisting of 1,267 males (35.86%) and 2,266 females (64.14%). The age group of 18-25 years accounted for the highest number, comprising 1,875 donors (53.07%). Among the deferred cases, 53.33% were first-time donors, followed by 25.28% regular donors and 21.40% lapsed donors. The deferral of blood donors resulted from various reasons. The most common cause of overall deferral among blood donors was low hemoglobin (38.33%), followed by upper respiratory tract infections (8.38%), chronic medical illness (7.08%), and high blood pressure (7.02%). Temporary deferrals were more prevalent than permanent deferrals, accounting for 91.57% of cases compared to 8.43% for permanent deferrals. Voluntary non-remunerative blood donors constitute the backbone for a safe and reliable blood supply in transfusion services. Utilizing a comprehensive database will enable effective counseling of temporarily deferred donors, providing insights into the reasons for their deferral, the expected duration, and the appropriate treatments. This information is crucial for motivating these donors to recruit again in the donor pool. Public education initiatives aimed at raising awareness about the causes of deferral and promoting regular health check-ups can play a pivotal role in minimizing these deferrals.

Platelet Additive Solutions as an Alternative Storage Medium of Apheresis Platelets to Reduce ABO Antibody Titer for ABO-Incompatibility Platelet Transfusion.

Introduction Platelet additive solutions (PASs) are nutrient media commonly used to replace and reduce the need for storage plasma. They are an alternative medium to maintain high-quality platelets lasting longer on the shelf for about seven days. Platelets with high titer of ABO antibody can pose a hemolytic transfusion reaction (HTR) risk if units are given across the ABO barrier. The risk of complication is greater when group O platelet is released to non-group O patients. The PAS has been known as a safe medium, where the titer of ABO antibodies is expected to be diluted. In this study, we compared the anti-A and anti-B antibody titers of apheresis platelets in PAS and non-PAS (plasma) as the suspending media. Methods A total of 20 apheresis platelet donors were selected, with seven from blood group A, eight from blood group B, and five from blood group O. The platelets were collected using an Amicus cell separator. They were suspended in PAS and plasma before being stored at a temperature range of 22-24º C. Anti-A (blood group B and O) and Anti-B (blood group A and O) antibody titers were measured and compared between the two suspending media. Wilcoxon signed-rank test is used for statistical analysis, and a p-value <0.05 is considered significant. Results The median titer of the anti-A antibody of apheresis platelets showed a significant difference between suspended in PAS (2.50) and plasma (4.00), p=0.002. Similar findings were also seen with the median titer of the anti-B antibody of apheresis platelet, in which it showed a significant difference between suspended in PAS (2.00) and plasma (4.00), p=0.004. It was observed that there was a significant reduction in both anti-A and anti-B antibody titers in the PAS as compared to the plasma group. Conclusion The decrease in ABO antibody titer in apheresis platelets stored with PAS can be beneficial for patients. This reduces the risk of HTRs if ABO-incompatible platelet units need to be issued. Thus, using PAS as a storage medium significantly improves platelet inventory management without compromising patient safety.

Significance of Zone 2 Peak on Capillary Electrophoresis in the Detection of Hemoglobin Constant Spring.

Objectives: Hemoglobin constant spring (Hb CS) is a point mutational defect associated with α thalassemia. The aims of this study were to compare the hematological profiles between different Hb CS genotypes and to estimate the range for Zone 2 peak using capillary electrophoresis (CE) with different Hb CS genotypes. Methods: For this cross-sectional study, patient blood samples that showed a positive peak in zone 2 of CE were selected. Hemoglobin and DNA of the samples were investigated to ascertain the presence and levels of non-deletional and deletional α thalassemia. The results were statistically analyzed. Results: Of the 137 samples investigated, 118 (86.1%) were positive for termination codon Hb CS mutation. Heterozygous Hb CS was found in 92 (67.2%), compound heterozygous Hb CS in 22 (16.1%), and homozygous Hb CS in four (2.9%) samples. The ranges of Hb CS level for heterozygous Hb CS, compound heterozygous Hb CS, and homozygous Hb CS were within 0.2-2.7%, 0.3-2.2%, and 4.5-5.5%, respectively. Significant hematological differences in the Hb level, mean cell volume, mean cell hemoglobin, red cell distribution width, red blood cell count, and Hb CS level were observed between heterozygous, homozygous, and compound heterozygous Hb CS. Conclusions: In view of the overlapping prevalence range of Hb CS level for heterozygous and compound heterozygous Hb CS, only Hb CS level within the range 4.5-5.5% was helpful in the diagnosis of homozygous Hb CS.

Red Blood Cell Alloimmunization and Its Associated Factors among Chronic Liver Disease Patients in a Teaching Hospital in Northeastern Malaysia.

Red blood cell (RBC) alloimmunization is an important complication of blood transfusion. Variations in the frequency of alloimmunization have been noted among different patient populations. We aimed to determine the prevalence of RBC alloimmunization and associated factors among chronic liver disease (CLD) patients in our center. This is a case-control study involving 441 patients with CLD who were being treated at Hospital Universiti Sains Malaysia and subjected to pre-transfusion testing from April 2012 until April 2022. Clinical and laboratory data were retrieved and statistically analyzed. A total of 441 CLD patients were included in our study, with the majority being elderly, with the mean age of patients 57.9 (SD ± 12.1) years old, male (65.1%) and Malays (92.1%). The most common causes of CLD in our center are viral hepatitis (62.1%) and metabolic liver disease (25.4%). Twenty-four patients were reported to have RBC alloimmunization, resulting in an overall prevalence of 5.4%. Higher rates of alloimmunization were seen in females (7.1%) and patients with autoimmune hepatitis (11.1%). Most patients developed a single alloantibody (83.3%). The most common alloantibody identified belonged to the Rh blood group, anti-E (35.7%) and anti-c (14.3%), followed by the MNS blood group, anti-Mia (17.9%). There was no significant factor association of RBC alloimmunization among CLD patients identified. Our center has a low prevalence of RBC alloimmunization among CLD patients. However, the majority of them developed clinically significant RBC alloantibodies, mostly from the Rh blood group. Therefore, phenotype matching for Rh blood groups should be provided for CLD patients requiring blood transfusions in our center to prevent RBC alloimmunization.

Acute hemolytic transfusion reaction following ABO-mismatched platelet transfusion: Two case reports.

Acute hemolytic transfusion reaction following ABO-incompatible platelet transfusion: two case reports An ideal platelet transfusion should provide ABO identical platelet concentrate, and cross match compatibility is not routinely performed in the standard practices. However, ABO non identical platelet transfusions are not uncommon with the limited resources and short shelf life of platelet concentrate. Though rare, acute hemolytic transfusion reaction (AHTR) may occur following minor ABO-incompatible platelet transfusion. Here, we report two cases of thrombocytopenic patients (one child and one adult) type as Group B RhD positive and received Group O RhD positive platelet transfusions. Both patients experienced an AHTR evidenced by a drop in hemoglobin level, spherocytosis and small agglutinations on the blood film, and positive direct Coombs test. They were treated symptomatically, recovered and discharged well post-event without any morbidity. No anti-B isohemagglutinins titer were done to confirm the high titer of the antibody in the platelet donors. Our cases highlighted the importance of ABO-compatible platelet transfusion, especially to children and those vigilant groups of patients.

Distribution of 22 Single Nucleotide Polymorphisms in 13 Cytokine Genes in Malays, Chinese, and Indians in Peninsular Malaysia.

Introduction: Cytokines are cell signaling glycoproteins that are particularly important in immunity and inflammatory responses. Therefore, variations, such as single nucleotide polymorphisms (SNPs), in genes encoding for cytokines may have important consequences for their roles in health. Materials and Methods: A total of 222 unrelated, healthy, and un-admixed Malays (n = 97), Chinese (n = 77), and Indians (n = 48) with a median age of 30 years old (range 21-50) were typed for 22 cytokine gene SNPs: IL-1α -889 T/C, IL-1ß (-511 T/C, +3962 T/C), IL-1R pst1 1970 T/C, IL-1RA mspa1 11100 T/C, IL-4Rα +1902 G/A, IL-12 - 1188 C/A, IFN-γ +874 A/T, TGF-ß (cdn 10 C/T, cdn 25 G/C), TNF-α (-308 A/G, -238 A/G) IL-2 (+166 G/T, -330 T/G), IL-4 (-1098 T/G, -590 T/C, -33 T/C), IL-6 (-174 C/G, nt565 G/A), and IL-10 (-1082 G/A, -819 C/T, -592 A/C). This involved using well-established polymerase chain reaction procedures with sequence-specific primers and restriction fragment length polymorphism methods. Results: The majority of the screened cytokine gene SNPs are polymorphic in all three ethnicities. Exceptions include TGF-ß cdn 25 (G/C), IL-1ß +3962 (T/C), and TNF-α -238 (A/G), which were all observed to be monomorphic in Malays, Chinese and Indians. Many of the analyzed cytokine gene SNP genotypes deviated from Hardy-Weinberg equilibrium and the three ethnic study groups were all well-separated from reference Asian, African and European populations in a principal component analysis plot. Conclusion: We successfully typed 22 SNPs in 13 cytokine genes from genetic material collected from unrelated and un-admixed Malay, Chinese and Indian individuals in Peninsular Malaysia. These new cytokine gene population datasets reveal interesting contrasts with other populations.

Single Nucleotide Polymorphisms in XMN1-HBG2, HBS1L-MYB, and BCL11A and Their Relation to High Fetal Hemoglobin Levels That Alleviate Anemia.

Anemia is a condition in which red blood cells and/or hemoglobin (Hb) concentrations are decreased below the normal range, resulting in a lack of oxygen being transported to tissues and organs. Those afflicted with this condition may feel lethargic and weak, which reduces their quality of life. The condition may be manifested in inherited blood disorders, such as thalassemia and sickle cell disease, whereas acquired disorders include aplastic anemia, chronic disease, drug toxicity, pregnancy, and nutritional deficiency. The augmentation of fetal hemoglobin (HbF) results in the reduction in clinical symptoms in beta-hemoglobinopathies. Several transcription factors as well as medications such as hydroxyurea may help red blood cells produce more HbF. HbF expression increases with the downregulation of three main quantitative trait loci, namely, the XMN1-HBG2, HBS1L-MYB, and BCL11A genes. These genes contain single nucleotide polymorphisms (SNPs) that modulate the expression of HbF differently in various populations. Allele discrimination is important in SNP genotyping and is widely applied in many assays. In conclusion, the expression of HbF with a genetic modifier is crucial in determining the severity of anemic diseases, and genetic modification of HbF expression may offer clinical benefits in diagnosis and disease management.

Challenges in the Diagnosis of Beta-thalassemia Syndrome: The Importance of Molecular Diagnosis.

Patients with heterozygous ß-thalassemia are generally asymptomatic. However, the intermediate phenotype is uncommon, and patients require further investigation to confirm the diagnosis. We describe a 32-year-old woman (gravida 3, para 2) with heterozygous ß-thalassemia who presented with symptomatic anemia and had a history of frequent blood transfusion in each pregnancy. Physical examination was unremarkable. Laboratory results at presentation showed hypochromic microcytic anemia with reticulocytosis. Molecular study revealed intermedia phenotypes resulting from coinheritance of heterozygous ß-globin chain mutation (IVS1-5) and a rare heterozygous α-globin triplication (αααanti-3.7). In this case report, we discuss the laboratory diagnostic approaches and the challenges faced in investigating this case.

A case of naturally occurring anti-Dia antibody in a young man.

The Diego (Di) blood group system comprises 22 antigens located on the band 3 protein, most of which are low-prevalence antigens. The majority of antibodies to Diego system antigens were of clinically insignificant; however anti-Dia, -Dib, -Wra, -ELO and-DISK may cause hemolytic disease of the fetus and newborn (HDFN) and transfusion reaction. We reported a case of naturally occurring of anti-Dia in a young man who presented to our hospital for wound debridement of fingers injury. His serological results were suggestive of anti-Dia antibody, and his molecular blood group showed he has Di (a-b+) antigen. Anti-Dia may be clinically significant. It can cause mild-to-severe HDFN, but there are only infrequent reports of it being clearly implicated in a hemolytic transfusion reaction. We suggest the need for reagent red blood cell panels to include Dia antigen-positive cells in antibody identification tests for our populations.

Blood Transfusion Knowledge among Nurses in Malaysia: A University Hospital Experience.

Blood transfusion is a fundamental and life-saving procedure where the consequence of errors can be fatal. Nurses' knowledge plays an essential role in ensuring quality and safety in blood transfusion. The objective of this study was to assess blood transfusion-associated knowledge of tertiary hospital nurses on the east coast of Malaysia. This was a cross-sectional study with 200 registered nurses involved in blood transfusion procedures at Hospital Universiti Sains Malaysia. The knowledge of the nurses was evaluated by using the routine blood transfusion knowledge questionnaire based on five parts, and <50%, 50-74%, or ≥75% of the knowledge was considered as poor, moderate, or high, respectively. Based on the scoring system, the overall knowledge of blood transfusion among Malaysian nurses (33.2 ± 8.4 years) was estimated to be 54.9 ± 7.6%. In individual items, the scoring was 81.0%, 45.4%, 49.2%, 63.0%, and 90.0% in knowledge prior to blood transfusion, on pre-transfusion, on post-transfusion, on complications, and on transfusion policy, respectively. The findings of this study indicated that most of the nurses' overall knowledge of blood transfusion was at a moderate level; therefore, training courses and continuous medical education are warranted to improve knowledge and skills of the nurses to ensure good practices of blood transfusion.

Prevalence of Red Blood Cell Alloimmunization among Transfused Chronic Kidney Disease Patients in Hospital Universiti Sains Malaysia.

OBJECTIVES: Red blood cell (RBC) immunization is a common complication in blood transfusion recipients. Patients with chronic kidney disease (CKD) eventually develop anemia, which is multifactorial, and requires regular blood transfusions, which exposes patients to the development of RBC antibodies. We sought to determine the prevalence and specificity patterns of RBC immunization and its risk factors among transfused CKD patients. METHODS: We conducted a cross-sectional study over one year from January to December 2018 in the Transfusion Medicine Unit, Hospital Universiti Sains Malaysia. A total of 249 samples were recruited from CKD patients who received a blood transfusion (at least one-pint), which only match for ABO and Rh(D) antigen. The serum was screened for the presence of the RBC antibody using the gel agglutination technique (Diamed gel cards). Samples with positive antibody screening were subjected to antibody identification. RESULTS: Of the 249 transfused CKD patients, 31 (12.4%) developed RBC immunization. Thirty (12%) were alloimmunized, and one (0.4%) was autoimmunized. Anti-Mia was the most common antibody (n = 14, 46.7%) among alloantibodies, followed by anti-E (n = 7, 23.3%). There was a significant association between pregnancy history with the development of antibodies whereas, no significant association was found between sociodemographic background, stage of CKD, hemodialysis status, underlying medical illness, and number of packed cell transfusions with the development of RBC antibodies. CONCLUSIONS: One-eighth of our patient cohort had RBC alloimmunization, and the risk was increased in patients with a history of pregnancy. We propose Rhesus RBC phenotyping and to supply blood match Rhesus antigen in CKD patients, especially patients of reproductive age.

Extreme Thrombocytosis in a Child: Laboratory Approaches and Diagnostic Challenges.

Thrombocytosis in children as well as in adult is defined as platelet count ≥ 450 × 109/L, and it is usually a reactive feature to various medical disorders. However, extreme thrombocytosis (platelet count ≥ 1000 × 109/L) is an uncommon finding among pediatric and adult patients, which may indicate more than a reactive phenomenon. We describe a case of a five-year-old boy who was admitted due to recurrent epistaxis. He had no history of allergic tendency or trauma. Physical examination was unremarkable except for shotty neck nodes. Laboratory results at presentation showed normal hemoglobin and total leukocyte count with eosinophilia (0.92 × 109/L), and extreme thrombocytosis. Other relevant investigations including coagulation profile, serum ferritin, liver, and renal function tests were all within normal ranges. Stool samples for ova and cysts were negative. The peripheral blood smear and bone marrow aspirate confirmed thrombocytosis with increased megakaryocytic proliferation and no artefactual reasons for the high platelets such as red blood cell fragments. Different causes of thrombocytosis in childhood were investigated after considering the possible differential diagnoses for extreme thrombocytosis.

Autologous Peripheral Blood Stem Cell Transplantation Among Lymphoproliferative Disease Patients: Factors Influencing Engraftment.

OBJECTIVES: Autologous peripheral blood stem cells transplantation (APBSCT) is a therapeutic option which can be used in various hematological, neoplastic disorders including lymphoproliferative disease (LPD). Differences in patient populations and treatment modalities in different transplant centers mean it is important to improve the knowledge of the different factors affecting engraftment after APBSCT for the success of this procedure. We sought to determine the factors influencing neutrophil and platelet engraftment after APBSCT in patients with LPD. METHODS: We conducted a retrospective review of 70 patients with LPD (35 with lymphoma and 35 with multiple myeloma) who had undergone APBSCT between January 2008 and December 2016. Data obtained included disease type, treatment, and stem cell characteristics. Kaplan-Meier analysis was performed for probabilities of neutrophil and platelet engraftment occurred and was compared by the log-rank test. The multivariate Cox proportional hazards regression model was used for the analysis of potential independent factors influencing engraftment. A p-value < 0.050 was considered statistically significant. RESULTS: Most patients were ethnic Malay, the median age at transplantation was 49.5 years. Neutrophil and platelet engraftment occurred in a median time of 18 (range 4-65) and 17 (range 6-66) days, respectively. The majority of patients showed engraftment with 65 (92.9%) and 63 (90.0%) showing neutrophil and platelet engraftment, respectively. We observed significant differences between neutrophil engraftment and patient's weight (< 60/≥ 60 kg), stage of disease at diagnosis, number of previous chemotherapy cycles (< 8/≥ 8), and pre-transplant radiotherapy. While for platelet engraftment, we found significant differences with gender, patient's weight (< 60/≥ 60 kg), pre-transplant radiotherapy, and CD34+ dosage (< 5.0/≥ 5.0 × 106/kg and < 7.0/≥ 7.0 × 106/kg). The stage of disease at diagnosis (p = 0.012) and pre-transplant radiotherapy (p = 0.025) were found to be independent factors for neutrophil engraftment whereas patient's weight (< 60/≥ 60 kg, p = 0.017), age at transplantation (< 50/≥ 50 years, p = 0.038), and CD34+ dosage (< 7.0/≥ 7.0 × 106/kg, p = 0.002) were found to be independent factors for platelet engraftment. CONCLUSIONS: Patients with LPD who presented at an early stage and with no history of radiotherapy had faster neutrophil engraftment after APBSCT, while a younger age at transplantation with a higher dose of CD34+ cells may predict faster platelet engraftment. However, additional studies are necessary for better understanding of engraftment kinetics to improve the success of APBSCT.

Hemolytic disease of fetus and newborn due to maternal red blood cell alloantibodies in the Malay population.

BACKGROUND: Maternal red blood cell (RBC) alloimmunization may lead to production of harmful antibodies that result in hemolytic disease of fetus and newborn (HDFN). There is insufficient data on the prevalence of HDFN due to RBC alloantibodies in the Malay neonatal population. AIM: The aim of this study was to determine the incidence of HDFN in the Malay neonatal population due to clinically significant RBC alloantibodies. SUBJECTS AND METHODS: A cross sectional study was conducted in Transfusion Medicine Unit, Hospital Universitiy Sains Malaysia over one year period from January to December 2009. A total of 5163 Malay pregnant women who attended labor room for delivery were collected and analyzed prospectively. The blood samples were subjected to the standard immunohematological procedure for RBC antibody screening and identification using reagents of Diamed-ID Gel microtyping system. All the newborns with RBC alloantibody were investigated for the evidence of HDFN. RESULTS: Thirty (0.58%) women were found to have clinically significant RBC alloantibodies. Most of the alloantibodies belonged to Rhesus (Rh) system (56.7%) where anti-E (33.3%) was the most common followed by anti-D (10.0%). Rh antibodies were the main cause of HDFN in fourteen (0.27%) neonates. Anti-D and anti-c were identified to cause moderate to very severe HDFN. CONCLUSIONS: With the low prevalence of clinically significant RBC alloantibodies and HDFN, routine antenatal antibody screening practice may not be advised as a routine practice at present, preferably reserved for those women of RhD negative or with history of HDFN, significantly of those attributed to anti-c.