Marne Abdullah

Background: Thromboembolic events (TEEs) are recognized complications in thalassaemia, arising from a hypercoagulable state driven by multiple proposed mechanisms. These concerns have prompted numerous investigations to better understand the underlying prothrombotic pathways. This study aimed to compare and correlate the levels of fragmented red blood cells (FRCs), hypercoagulable protein markers, and erythrocyte phosphatidylserine (PS) exposure in thalassaemia patients. This 12-month prospective case-control study at HPUSM recruited 34 thalassaemia patients (21 with thalassaemia major and 13 with thalassaemia intermedia) and 10 healthy controls. Methods: FRCs, erythrocyte PS, protein C, free protein S, and antithrombin III levels were measured. Results: A total of 44 subjects were included, with a mean age of 22.43 ± 10.45 years; most were male (61.4%) and Malay (86.4%). Median FRCs and PS exposure were significantly elevated in both thalassaemia groups compared to controls (p < 0.001 for FRCs; p = 0.048 for PS). Mean protein C and free protein S levels were significantly reduced in thalassaemia major (55.00 ± 10.20% and 65.77 ± 8.66%) and thalassaemia intermedia (61.23 ± 16.99% and 61.11 ± 14.65%) compared to controls (101.60 ± 18.97% and 95.12 ± 23.57%) (p < 0.001 for both), while antithrombin III levels were not significantly different. A significant negative correlation was observed between PS exposure and protein C (p = 0.014). Protein C was positively correlated with free protein S (p = 0.021) and antithrombin III (p < 0.001). Conclusions: Elevated PS exposure and reduced protein C and free protein S levels in thalassaemia patients indicate a potential procoagulant phenotype.

Background: Acquired hemophilia A (AHA) develops due to autoantibodies directed against factor VIII. It can occur spontaneously or be triggered by various factors. Here, we report a case of AHA induced by the Pfizer-BioNTech COVID-19 vaccine in an older patient. Case presentation: The patient presented with multiple spontaneous bruises after receiving the Pfizer-BioNTech COVID-19 vaccine. Laboratory investigations revealed an isolated prolonged activated partial thromboplastin time (APTT) with an uncorrected mixing test. The factor VIII level was found to be low (0.6%). Additionally, the Bethesda assay evidenced the presence of an inhibitor of factor VIII. The patient was administered IV methylprednisolone and recombinant factor VIII. Then, he was maintained with oral azathioprine and prednisolone. However, the patient's condition showed no significant improvement. Thus, rituximab was administered, to which the patient responded well. Discussion and conclusion: AHA is a rare adverse effect of the Pfizer-BioNTech COVID-19 vaccine. Although the exact mechanism underlying the development of this condition following vaccination against COVID-19 remains unclear, a diagnosis of AHA should be considered if a patient without a bleeding history presents with acute-onset bleeding and an isolated prolonged APTT.

Hb Adana is a non-deletional α-thalassaemia variant, due to mutations in α1- or α2-globin codon 59 (αCD59) that produce unstable α-globin. Clinical appearance can range from silent carrier to blood transfusion reliance, hepatosplenomegaly, skeletal deformities, and spinal cord compression. Despite the importance of Hb Adana inheritance, this Hb variant is challenging to study since molecular tests are scarce and routine diagnosis can be missed. This study explored the distribution of Hb Adana among local high school students and evaluate the hematological parameters and haemoglobin analysis of Hb Adana in this region of Malaysia. This retrospective study included 13,721 blood samples from high school students enrolled in Malaysia's National Thalassaemia Screening Program at Hospital Raja Perempuan Zainab II (HRPZ II). Multiplex Gap PCR was used to detect deletional α-thalassaemia. Common non-deletional α-thalassaemia was detected using multiplex ARMS PCR. Evaluable data were retrieved from the HRPZ II database. Results: A total of 2327 subjects exhibited common deletional (n=1037, 44.6%) and non-deletional (n=1290, 55.4%) α-thalassaemia. Hb Constant Spring was the most frequent non-deletional α-thalassaemia. Thirty-one participants (1.33%) had αCD59α/αα and one (0.04%) had αCD59α/-α3.7. The 32 Hb Adana subjects were 87.5% Malay, and 12.5% Orang Asli. Additionally, seven cases of HbE/Hb Adana were discovered. The haemoglobin level in heterozygous Hb Adana ranged from mild anaemia to normal, 95.0 g/L to 153.0 g/L. The MCV and MCH were approximately 73 fL and 23 pg, respectively. Conclusions: We have denoted the distribution of alpha thalassaemia mutation patterns among high school students in Kelantan, Northeast Peninsular of Malaysia. Our observation showed Hb Adana was rarely uncommon in our region and the co-inheritance with an α-gene deletion generates α+-thalassaemia; with HbE, α0-thalassaemia. All heterozygous Hb Adana exhibited low MCVs and MCHs.

Thalassemia is identified as a prevalent disease in Malaysia, known to be one of the developing countries. Fourteen patients with confirmed cases of thalassemia were recruited from the Hematology Laboratory. The molecular genotypes of these patients were tested using the multiplex-ARMS and GAP-PCR methods. The samples were repeatedly investigated using the Devyser Thalassemia kit (Devyser, Sweden), a targeted NGS panel targeting the coding regions of hemoglobin genes, namely the HBA1, HBA2, and HBB genes, which were used in this study. There were many different genetic variants found in 14 unrelated cases. Out of all fourteen cases, NGS was able to determine an additional -50 G>A (HBB:c.-100G>A) that were not identified by the multiplex-ARMS method, including HBA2 mutations, namely CD 79 (HBA2:c.239C>G). Other than that, CD 142 (HBA2:c.427T>C) and another non-deletional alpha thalassemia and alpha triplication were also not picked up by the GAP-PCR methods. We illustrated a broad, targeted NGS-based test that proposes benefits rather than using traditional screening or basic molecular methods. The results of this study should be heeded, as this is the first report on the practicality of targeted NGS concerning the biological and phenotypic features of thalassemia, especially in a developing population. Discovering rare pathogenic thalassemia variants and additional secondary modifiers may facilitate precise diagnosis and better disease prevention.

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.