Blood Grouping Research Articles

Hemagglutination Assay via Optical Density Characterization in 3D Microtrap Chips.

Hemagglutination assay has been used for blood typing and detecting viruses, thus applicable for the diagnosis of infectious diseases, including COVID-19. Therefore, the development of microfluidic devices for fast detection of hemagglutination is on-demand for point-of-care diagnosis. Here, we present a way to detect hemagglutination in 3D microfluidic devices via optical absorbance (optical density, OD) characterization. 3D printing is a powerful way to build microfluidic structures for diagnostic devices. However, mixing liquid in microfluidic chips is difficult due to laminar flow, which hampers practical applications such as antigen-antibody mixing. To overcome the issue, we fabricated 3D microfluidic chips with embedded microchannel and microwell structures to induce hemagglutination between red blood cells (RBCs) and antibodies. We named it a 3D microtrap chip. We also established an automated measurement system which is an integral part of diagnostic devices. To do this, we developed a novel way to identify RBC agglutination and non-agglutination via the OD difference. By adapting a 3D-printed aperture to the microtrap chip, we obtained a pure absorbance signal from the microchannels by eliminating the background brightness of the microtrap chip. By investigating the underlying optical physics, we provide a 3D device platform for detecting hemagglutination.

The Spectrum of ABO and Rhesus Blood Group Systems in a Blood Center in Southern Karnataka

Introduction: Hereditary characteristics, such as ABO and Rhesus (Rh) blood group antigens, are helpful for population genetic studies, for settling medicolegal disputes, and most vitally immunologic safety of blood during transfusion. Having firm knowledge of blood grouping is essential for managing the collection of blood banks. It can lower the likelihood of morbidity and mortality brought on by lack of blood in specific areas. The objective of our study was to screen and determine the frequencies of the occurrence of ABO and Rh blood groups among residents from both the urban and rural populations of the South Karnataka region. Materials and Methods: This was a retrospective study. The study was conducted in a blood center and included all the donors from January 17 to December 22. Hemoglobin estimation was estimated by copper sulfate method and ERMA INC-PCE-210 3-Part analyzer. After blood bank validation, Tulip Diagnostics Limited standard anti-sera of anti-A, anti-B, and anti-D were used to conduct antigen–antibody slide agglutination test to determine the ABO grouping and Rh typing following blood donation. Simple percentages were used to report data on the ABO and Rh blood group distribution patterns. Results: Out of 19497 donors, predominant age group was 25–29 years (29.46%). The male:female ratio was 108:1. Voluntary donors (91.03%) were more than replacement donors, with predominant donors being Rh positive. Maximum donors had the blood group O (42.5%), followed by B > A > AB. There were also four Bombay blood group donors in our study. Conclusion: Good knowledge and understanding of blood grouping have an imperative involvement in the management of blood bank inventory. It can help to minimize the morbidity and mortality rate due to lack of blood in a particular geographical area.

Triad of Cheiloscopy, Dactyloscopy, and Blood Groups: Does it Signify Anything?

The knowledge and importance of blood groups emerged from transfusion medicine and its relation with certain malignancies has been proven. Its importance in forensic medicine was brought to light when its association was found with the distribution of finger patterns. Thus, few studies exist proving the relationship between dactyloscopy and blood groups. Cheiloscopy on other hand is the study of the irregularities present on the lips forming a unique arrangement called the prints of the lip. Our paper aims at elucidating any unique combination if any that exists between prints on lips, prints of fingers, and blood grouping in a specific population, which might help in the identification of an individual. A total of 100 subjects of age varying from 15 to 40 years were included in the study. Subjects comprised of 50 males and 50 females. All the subjects were examined and their prints of lips along with prints of their fingers were taken. Blood groups were determined for each patient using the ABO system. Type I was found to be the predominant pattern of lips and whorl arrangement was the most recorded type of fingerprint in males whereas Type II arrangement along with loop prints of fingers was most observed in the case of females. The most common blood group in males was B+ and in females was O+ . Correlation between three parameters was obtained by Pearson correlation statistical analysis. The prints of the lips and fingers of an individual have never been similar and they tend to remain the same from a person's birth until his death. An association between the three things of an individual that is prints of lips, fingers, and his blood group has been tried to be elucidated through the present research to aid in forensic identification.

A Retrospective Study on Smell Dysfunction in COVID-19 Patients Presenting to a Tertiary Care Teaching Hospital in Northern India

Introduction: The smell dysfunction in COVID-19 patients has remained an unexplained topic. The blood parameters’ variability in COVID-19 patients with anosmia has been studied in few literatures. The study is aimed to find the association of anosmia with the blood grouping and C-reactive protein (CRP) levels in coronavirus-infected patients. Materials and Methods: Database from Medical Records Department of a Tertiary Care Teaching Hospital in Northern India was searched from July 2020 to December 2020. Every fifth file was selected using the stratified random sampling. Laboratory-confirmed COVID-19 cases by reverse transcription-polymerase chain reaction files were included. Blood grouping and CRP levels were assessed and statistically correlated. Results: A total of 103 patients of coronavirus-associated infection with anosmia were included among which 52 (50.48%) patients were from moderate category of AIIMS-ICMR joint task Force’s clinical guidelines. A total of 44 (42.71%) patients had moderate levels of elevated CRP. The blood Group B-type was found most commonly in 35 (33.98%) patients. The correlation of severity of COVID-19 infection with CRP was found to be statistically significant (Chi-square test statistic was 31.203 and P = 0.00023) in patients presenting with smell dysfunction. Conclusion: Anosmia was found to a suggestive symptom for the early identification of coronavirus-infected cases. In this study, CRP levels showed statistically significant association with anosmia in COVID-19 patients. Predilection for specific blood groups serves as platform for further research.

Retrospective study of canine blood xenotransfusion compared with type-matched feline blood allotransfusion to cats: indications, effectiveness, limitations and adverse effects.

Xenotransfusion is the transfusion of blood from one species to another. With varying availability of allogenic feline blood (AFB) and in emergency conditions, circumstances occur when canine blood is transfused to cats. This study aimed to characterise the indications, effectiveness, limitations, and acute and late transfusion-related adverse effects of canine blood xenotransfusion compared with matched AFB to anaemic cats, and their survival and longer-term outcome. This retrospective study (2013-2020) examined cats receiving canine blood xenotransfusions or AFB. The study included 311 cats (xenotransfusion [X-group], n = 105; allotransfusion [A-group], n = 206). Xenotransfusion was more frequent among cats sustaining haemorrhage than in those with haemolysis (P <0.01) or hypoproliferative anaemia (P <0.001). Financial constraints were the most common reason to elect xenotransfusion (49%). The post-transfusion mean packed cell volume was higher (P <0.001) in the X-group (22%) compared with the A-group (18%), and also higher (P <0.001) at 48-96 h post-transfusion (23% vs 18%, respectively). Transfusion-related adverse effects (TRAEs) were more frequent (P = 0.001) in the X-group (37.1%) compared with the A-group (19.4%), as were delayed haemolytic transfusion reactions (85% vs 42.5%, respectively; P <0.001). Acute transfusion reactions (ATRs) were more frequent (P <0.001) in the A-group (60%) compared with the X-group (20%). TRAEs were unassociated with survival to discharge. The survival to discharge rate of the X-group (55%) was lower (P = 0.007) than in the A-group (73%), while post-discharge survival rates to 30 days of cats surviving to discharge were 90% and 88%, respectively (P = 0.85). Canine blood xenotransfusions to cats might save lives in emergency conditions when AFB is unavailable or blood typing is infeasible. The survival to discharge rate of the X-group was lower than that of the A-group. The longer-term survival rate of cats administered xenotransfusions and surviving to discharge from the hospital was good.

Association of HLA class II DR/DQ alleles in children and adolescents with rheumatic heart disease from a tertiary care centre in North India

IntroductionRheumatic fever and RHD constitutes an important public health problem in India. The relatively low attack rate of RF, the high concordance rate for RF in monozygotic twins (19%) compared to dizygotic twins (2.5%), and the high familial incidence of RF suggest the involvement of host genetic factors in susceptibility to RF with consequential progression to RHD. ObjectiveTo study the association of HLA CLASS II DR/DQ alleles in children and adolescents with RHD from a tertiary care center in North India. Methods30 RHD patients and 30 age and sex-matched controls were included in our study and blood samples for HLA typing were processed through LAB Type™ reverse SSO DNA typing method. The assignment of the HLA typing was based on a comparison with already published HLA gene sequences. ResultsThe mean age of RHD patients and matched control groups were 12.97 ± 2.95 and 11.93 ± 3.23, respectively. In the cases and control group, males accounted for 63.3% and 50% of the patients respectively. A significant difference was found between the cases and controls for HLA DR∗ 15 (p-value 0.002), HLA DR∗ B4 (p-value 0.045), HLA DR∗ B5 (p-value 0.017), and HLA DQB1∗ 02 (p-value 0.005). ConclusionOur study suggests that HLA class II haplotypes may provide insight into the molecular mechanism of RHD and be a useful tool in predicting the clinical outcome in RF patients, thereby affording new means of intervention or vaccine design. Larger studies are needed to address this in our population.

Haemolysin test, ABO and Rhesus Blood grouping in Relation to occurrence of stillbirth, Miscarriage and transfusion status among Pregnant Women in University of Calabar, Nigeria

Introduction: Human red blood cells contain on their surface a series of glycoproteins and glycolipids which constitute the blood group antigens, which are also related to many clinical problems associated with transfusion reactions Aim of study: This study is aimed at providing information on the ABO and Rhesus Blood grouping in Relation to occurrence of stillbirth, Miscarriage and transfusion status among pregnant women attending Antenatal Clinic in University of Calabar Teaching Hospital, Calabar Nigeria. Materials and Methods: A descriptive cross-sectional study comprising of 400 pregnant women, aged 16 – 45years and who gave their informed consent was used. ABO and Rhesus blood groups were analysed using commercially prepared reagent. Haemolysin test and antibody screening were performed using standard cells. Results: Most of the pregnant women were aged 16 – 36 years and no underweight pregnant women were recorded in this study. The prevalence of ABO blood group among the pregnant women showed the decreasing order of O&gt;A&gt;B&gt;AB. It was observed that blood group O appeared about 3 times the prevalent of each group. The prevalence of Rhesus positive and Negative was 95% and 5% respectively. 5.5% of stillbirth was recorded while miscarriage had a prevalence of 17%. Approximately 5% of the pregnant women received blood transfusion. Rhesus blood group was found to be associated with still-birth (P=0.004). Conclusion: ABO blood group distribution was in the order O&gt;A&gt;B&gt;AB 63%, 20%, 14% and 3.0%. On the other hand, the study shows the prevalence of Rhesus D’ positive and Rhesus D’ negative to be 95% and 5% respectively. Blood group ‘O’ and rhesus positive blood group were predominant in stillbirth, miscarriages and transfusion status. It is recommended that the use of group O blood free from haemolysin α and β should only be transfused to pregnant women because of risk to the foetus.

Distribution of ABO and Rhesus (RHD) blood groups among blood donors in Republic of Congo

Aims: The ABO and Rhesus (Rh) blood group systems are most important in population genetic study and for blood transfusion purposes. This study was conducted to determine the distribution of ABO and Rh blood groups among Congolese blood donors. Methods: A retrospective study was conducted at National Center for Blood Transfusion, over a period of 5 years from January 1, 2011, to December 31, 2015. This study included the blood transfusion centers of Brazzaville, Pointe Noire and other localities grouped together in the North and Southwest coordination. Blood grouping ABO and Rhesus were determined using conventional blood typing procedures based on Beth-Vincent and Simonin-Michon methods. Results: Out of 266,055 blood donors included, 217,990 (81.9%) were male and 48,065 (18.1%) were female donors. Most donors were young adults, representing the age group of 18–30 (45%). The majority were replacement (62.4%) while the remainder was voluntary donors (37.6%). The most prevalent blood group was O (56.6%), followed by blood groups A (20.3%) and B (20.1%), whereas the least prevalent blood group was AB (2.9%). The majority 97.6% were Rh D positive, and 2.4% were Rh D negative. Conclusion: The study has a significant implication regarding the inventory management of blood transfusion center in Republic of Congo.

Association of β-Thalassemia and its Types with ABO and Rh Blood Groups in Lahore, Pakistan

The current study aims to determine the relationship of ß-thalassemia and its types (major, minor, intermedia) with ABO and Rh blood groups in Lahore, Pakistan. It is an observational study in which ABO and Rh blood grouping of 711 β-thalassemia patients was performed (with their consent). Blood grouping was performed through forward and reverse grouping using tube method. The observed ABO blood group pattern in both genders was O&gt;B&gt;A&gt;AB. It was found that the overall frequency of O and A blood groups was higher in female patients, while the frequency of B and AB blood groups was higher in male patients, although the difference was non-significant. However, a significant difference was observed in the relationship between gender and Rh factor. Most patients of β-thalassemia suffered from the type β-thalassemia major (48%), followed by patients suffering from β-thalassemia minor (44%) and β-thalassemia intermedia (8%). Overall, patients with AB blood group mostly suffered from β-thalassemia major, while patients with β-thalassemia minor and β-thalassemia intermedia had the highest frequency of blood group B. It was concluded that ß-thalassemia patients have a higher frequency of O+ blood group and the lowest frequency of AB- blood group. Moreover, a significant difference was seen between male and female patients with respect to Rh blood group. However, no significant difference (p &gt; 0.05) was found in the distribution of ABO and Rh blood groups corresponding to β-thalassemia types.

ABO Blood Type and Metabolic Markers in COVID-19 Susceptibility and Severity: A Cross-Sectional Study.

Background and Aims: To evaluate the effect of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus on the function and metabolic changes, as well as the relationship of the virus with blood groups. Methods and Results: This cross-sectional study included a matched sample of adult individuals with coronavirus disease 2019 (COVID-19) (n = 114) or without (controls; n = 236). Blood samples were collected and processed for triglycerides (TGs), total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, and blood typing analysis. The results showed that subjects with COVID-19 had higher TG and lower HDL-C levels compared with the control group. As for blood typing, the risk of COVID-19 was higher in subjects with blood group A than in those with blood group B and in those with other blood groups. In addition, an association of COVID-19 with blood type and Rh A- was observed. When related to the severity of COVID-19 symptoms, blood type A was more protective against moderate/severe symptoms compared with blood type O. In addition, individuals with blood type O were 2.90 times more likely to have symptoms moderate/severe symptoms of COVID-19 than those with other blood groups and individuals with type A blood were less likely to have severe/moderate symptoms of COVID-19 compared with individuals without type A blood. Conclusion: The results suggest that blood type may play a role in susceptibility to SARS-CoV-2 infection and add evidence that infection with the novel coronavirus may be associated with changes in lipid metabolism.

Novel blood typing method by discrimination of hemagglutination and rouleaux using an erythrocyte aggregometer.

In pretransfusion blood typing, pretreatments such as centrifugation and suspension of red blood cells (RBCs) and mixing them with sufficient amounts of reagents are required, but these steps are time-consuming and costly. Aiming to develop a new blood typing method that requires no dilution and only a small amount of reagent, we attempted to determine blood type using syllectometry, an easy-to-use and rapid optical method for measuring the RBC aggregation that occurs when blood flow is abruptly stopped in a flow channel. Samples of whole blood from 20 healthy participants were mixed with antibody reagents for blood typing at mixing ratios of 2.5% to 10% and measured with a syllectometry device. Amplitude (AMP), one of the aggregation parameters, showed significant differences between agglutination and non-agglutination samples at mixing ratios from 2.5% to 10%. Although there were significant individual differences in aggregation parameters, calculation of AMP relative to that of blood before reagent mixing reduced the individual differences and enabled determination of blood type in all participants. This new method enables blood typing with a small amount of reagent, without the time-consuming and labor-intensive pretreatments such as centrifugation and suspension of RBCs.

Neonatal hemolytic disease: How should we use indirect and direct antiglobulin tests?

In newborns with hemolysis, the direct antiglobulin test (DAT) and indirect antiglobulin test (IAT) play a key role in demonstrating the presence of an immune cause. We aimed to emphasize the importance of IAT in mothers of DAT-positive babies. DAT was performed with forward blood grouping on cord blood in term babies who were born between September 2020 and September 2022. IAT was performed in the mothers of the babies who were found to have a positive DAT and antibody identification was performed in the mothers who were found to have a positive IAT. Specific antibodies detected and identified were associated with the clinical course. The study included 2769 babies and their mothers. The prevalence of DAT positivity was found to be 3.3% (87 of 2661). In DAT-positive babies, the rate of ABO incompatibility was 45.9%, the rate of RhD incompatibility was 5.7% and the rate of RhD and ABO incompatibility in association was 10.3%. The rate of subgroup incompatibility and other red blood cell antibodies was 18.3%. Phototherapy was applied because of indirect hyperbilirubinemia in 16.6% of the DAT-negative babies and in 51.5% of the DAT-positive babies. The need for phototherapy was significantly higher in DAT-positive infants (p<0.01). Severe hemolytic disease of the newborn, bilirubin level, duration of phototherapy and use of intravenous immunoglobulin were found to be significantly higher in the babies whose mothers were IAT positive compared with the babies whose mothers were IAT negative (p<0.01). IAT should be performed on all pregnant women. When screening with IAT is not performed during pregnancy, performing DAT in the baby plays a key role. We showed that the clinical course was more severe when mothers of DAT-positive babies were IAT positive.

Analyzing the Interaction Between ABO Blood Types, Fingerprints, and Lip Prints among the Individuals of Lahore Region-A Research Article

Each person has a distinct lip printing and finger print, which are both utilized for personal identification and criminal investigations. Objective: To investigate the interaction between ABO blood group, lip prints and finger prints among both male and female participants. Methods: The study was conducted on 750 females and 550 males aged 18-50 from Lahore. Lip prints were classified using Tsuchihashi or Suzuki classification, while finger prints were classified using Kucken's or Michael's classification. Results were analyzed statistically using Microsoft Excel and SPSS version-21. Results: The pattern of loop was most common among the study group n = 1300 males (278 (50.55%), followed by Loop finger prints in 325 (43.30%) females. The most common blood type was AB+V 420(30%) among both groups. Both genders contain Type I lip pattern. The most common group of blood with fingerprint combination was AB+ve-Loop. AB+ve-Type I was the most common blood group versus lip print combination, with 104 individuals. Among the combination of lip prints or finger prints, Composite Type V had a smaller number of individuals. Both males and females scored 72. The composite type V-composite consists of A-ve, B-ve, AB-ve, or O-ve which showed the least common occurrence among the study group. Conclusions: Although blood typing, fingerprints, and lip prints each had unique characteristics. The correlation plays important role in identifying a certain person.

Comparison of the conventional tube and erythrocyte-magnetized technology in titration of red blood cell alloantibodies

Erythrocyte alloantibodies are mainly produced after immune stimulation, such as blood transfusion, pregnancy, and transplantation, and are the leading causes of severe hemolytic transfusion reactions and difficulty in blood grouping and matching. Therefore, antibody screening is critical to prevent and improve red cell alloantibodies. Routine tube assay is the primary detection method of antibody screening. Recently, erythrocyte-magnetized technology (EMT) has been increasingly used in clinical practice. This study intends to probe the application and efficacy of the conventional tube and EMT in red blood cell alloantibody titration to provide a reference for clinical blood transfusion. To investigate the application value of conventional tube and EMT in red blood cell alloantibody titration and enhance the safety of blood transfusion practice. A total of 1298 blood samples were harvested from blood donors at the Department of Blood Transfusion of our hospital from March 2021 to December 2022. A 5 mL blood sample was collected in tubing, which was then cut, and the whole blood was put into a test tube for centrifugation to separate the serum. Different red blood cell blood group antibody titers were simultaneously detected using the tube polybrene test, tube antiglobulin test (AGT), and EMT screening irregular antibody methods to determine the best test method. Simultaneous detection was performed through the tube polybrene test, tube AGT and EMT screening irregular antibodies. It was discovered that the EMT screening irregular antibody method could detect all immunoglobulin G (IgG) and immunoglobulin M (IgM) irregular antibodies, and the results of manual tube AGT were satisfactory, but the operation time was lengthy, and the equipment had a large footprint. The EMT screening irregular antibody assay was also conducted to determine its activity against type O Rh (D) red blood cells, and the outcomes were satisfactory. Furthermore, compared to the conventional tube method, the EMT screening irregular antibody method was more cost-effective and had significantly higher detection efficiency. With a higher detection rate, the EMT screening irregular antibody method can detect both IgG and IgM irregular antibodies faster and more effectively than the conventional tube method.

Patient and specimen identification in a tertiary care pediatric hospital: Barcodes do not scan themselves.

Despite the safety improvements linked to the use of barcodes for patient and specimen identification, patient misidentification remains a leading cause of transfusion-associated reactions including fatalities. A wealth of evidence supports the use of barcodes in general, but there is less published evidence of real-world barcode compliance. This project investigates barcode scanning compliance for patient and specimen identification at a tertiary care pediatric/maternity hospital. Transfusion laboratory specimen collection noncompliance events between January 1, 2019, and December 31, 2019 were retrieved from the hospital laboratory information system. Data were analyzed including stratification of collections by collector role and collection event. A survey of blood collectors was conducted. Collection compliance for 6285 blood typing specimens was evaluated. Full barcode scanning identification of both patient and specimen was utilized in only 33.6% of total collections. The remaining two thirds of collections were overridden by the blood collector: no barcode scanning occurred in 31.3%, while the specimen accession label was scanned but not the patient armband in 32.3% of total collections. There were significant differences between phlebotomists and nurses, with more phlebotomists performing the full scanning and specimen scanning only, while more nurses obtained specimens without patient or specimen scanning (p < .001). Blood collectors identified hardware challenges and training gaps as key contributors to barcode noncompliance. Our study highlights an instance of poor barcode scanning compliance for patient and specimen identification. We formulated improvement strategies and launched a quality improvement project to address factors influencing noncompliance.

Evaluate of newborn with jaundice at central teaching hospital of pediatrics in Baghdad : descriptive study

Background: - Neonatal jaundice is a frequent condition at newborns, particularly in the first few days after delivery, and it has to be treated well to prevent complications that might have significant, long-lasting complications.&#x0D; Objective: - To assess the outcome of newborn jaundice at the central teaching Hospital of pediatrics in Baghdad using different modality of treatments.&#x0D; Patients and Methods: - A retrospective study is done depending on the medical data of infants have jaundice who were admitted to the neonate units of the central teaching hospital within the period of a year, from May 1st 2020 to May 1st 2021. Blood grouping and total serum bilirubin measurements were taken in each case. Phototherapy, strong phototherapy, and exchange transfusion were utilized to treat the newborn jaundice, depending on its severity.&#x0D; Results: Total neonates admitted from 1st may2020 to1st may 2021 in neonate unit were 2508 and 855 [34%] have jaundice. the male: female rati0 is [1.6:1], males 516[60.3%], females 339[39.6%]. The Physiol0gical jaundice is the often-frequent cause 285[33.3%] patients. The Prematurity seen in 171[20%] patient and the ABO incompatibility seen in 128[1.3%] and the Rh incompatibility 17[2%] patient, the sepsis found in 16[2%] case and the other causes of hyperbilirubinemia seen in 238[27.8%] patient. the Phototherapy is the most frequent kind of management used in 513[55%] and intensive phototherapy is applied for 342[40.3%] patients and just 59[7%] of patients treated with exchange transfusion particularly patients with ABO incompatibility 25 [42%] also Rh incompatibility 34 [57.6%] Good decline in TSB level and not require the exchange transfusion is 812 [95%] of patients. Majority of infants 849 [99.55%] discharge with clinical improvement and only 17 [0.3%] of infant’s patients develops kernicterus and 8 patients is dying [0.1%]&#x0D; Conclusion: Moderate to severe hyperbilirubinemia is still often treated with phototherapy. Intensive phototherapy is beneficial in lowering T.S.B levels, minimizing the need for exchange transfusions, and shortening hospital stays in patients with newborn hyperbilirubinemia.

Relationship between the ABO blood group and the severity of COVID-19 patients

Patient with severe COVID-19 may have exaggerated defense response causing Systemic Inflammatory Response Syndrome (SIRS). Antibody, one of immune response, not only fights foreign substances but also used as blood grouping. This study aims to determine the relationship between blood group and severity of COVID-19 symptoms. This is a retrospective descriptive study. The data was taken cross-sectionally on COVID-19 subjects confirmed RT-PCR positive with severe and non-severe degrees with blood type examination results. The secondary data were taken from the Laboratory Information System and medical records on period January-December 2020. The statistical analysis uses chi-square. From 92 subjects, the most common blood group among all COVID-19 patients (in order) is O (40,2%), A (28,3%), B (22,8%), AB (8,7%) among the severe patient group is A (37.0%) among the non-severe patient group is O (47.8%) p>0.05 while among the subject with comorbidities (76.1%) p<0.05 is A (40.0%). Anti-A antibody is more protective and it blocks the interaction between SARS-CoV-2 and ACE-2 receptor. The absence of anti-A in blood group A and AB causes these blood groups found in the severe patient group. The presence of anti-A in blood types O and B causes the majority of non-severe degree. Although there is no significant difference between severe and non-severe groups based on blood group, Anti-A antibodies are more protective and blocks the interaction between SARS-CoV-2 and the ACE-2 receptor.

Association Between ABO-RHD Blood Groups and COVID-19: A Preliminary Study of 76 Cases

<i>Introduction: </i>Blood types are most often incriminated in susceptibility to COVID-19. Blood group O subjects are reportedly less susceptible to COVID-19. However, these reports are mainly from countries with high infection rates. The overall objective of this study was to investigate the association between the risk of COVID-19 infection, its severity, and ABO-RHD blood groups at the Training Hospitals of Bouake and Cocody (Ivory Coast). <i>Material and methods: </i>This was a prospective study that lasted four months. All patients with COVID-19 at the time of the study and followed at the Training Hospitals of Bouake and Cocody, hospitalized in the COVID-19 centers or in home confinement, were included. T lymphocyte subpopulations were counted on the BD FACS Calibur flow cytometer after labeling. ABO and RHD blood typing was performed in all patients. <i>Results: </i>Of the 76 patients collected, 78.9% were homebound, 18.4% in hospital and 2.6% in the ICU. The mean age was 41.92 ± 15.13 years with a male predominance. The majority of hospitalized patients were significantly of blood group A (p=0.020). CD4 and CD8 T lymphopenia were significantly more frequent in patients with blood group A than in those with blood groups B, AB and O. <i>Conclusion: </i>The impact of blood group on the severity of the disease would exist. Our study showed that blood group A subjects were more likely to have COVID-19. In addition, a statistically significant association between blood type A and CD4 and CD8 T lymphopenia was found. These results should be confirmed by studies based on larger patient samples.

Association Between HLA Polymorphisms and Sympathetic Ophthalmia in Han Chinese

ABSTRACT Purpose Sympathetic ophthalmia (SO) is considered as an autoimmune disease with unclear mechanisms. This study investigated the relationship between HLA polymorphisms and SO. Methods HLA typing was performed using the LABType reverse SSO DNA typing method. The allele and haplotype frequencies were assessed using the PyPop software. Statistical significance of genotype distributions between 116 patients and 84 healthy individuals (control) was determined using Fisher’s exact test or Pearson's chi-squared test. Results The SO group had a higher frequency of HLA-DRB1 * 04:05, HLA-DQB1 * 04:01, DRB1 * 04:05-DQB1 * 04:01 haplotype as compared to the control group (Pc < 0.001 for all). Conclusion This study revealed that DRB1 * 04:05 and DQB1 * 04:01 alleles, as well as DRB1 * 04:05-DQB1 * 04:01 haplotye could be potential risk factors for SO.

PREVALENCE OF BLOOD GROUPA2 AMONG GROUPAAND AB DONORS

The ABO blood group antigens are clinically signicant and their discovery by Landsteiner in 1900 paved way for the performance of safe blood transfusions. These antigens are characterized by their distinct carbohydrate structures attached to the glycoprotein or glycolipid membranes of red blood cells (RBCs). Their expression can also be detected on various human cell and tissue surfaces including sensory neurons, vascular endothelium and platelets. [1] Subgroups of the ABO antigens occur and are characterized by reduced quantities of the antigens on the RBCs and saliva of secretors. [2] Landsteiner &amp; Levine subdivided blood group A into their principal subgroups, A1 and A2. The presence of Asubgroups is due to genetic variations in the coding region which leads to diminished amounts of A substance and higher amounts of H substance on red blood cells. There are weaker subgroups than A2 which do not frequently occur but when present; they show a characteristic decreased Aantigen sites on their RBC and a corresponding increased H antigen activity. [3] The difference between subgroups A1 and A2 is seen in their reactivity with the Dolichos biflorus lectin. The Dolichos lectin specically agglutinates A1 cells, leaving the A2 cells unagglutinated. The ABO antibodies occur naturally in the sera of individuals who do not have the corresponding antigens and can cause haemolysis in-vivo. They are mostly immunoglobulin M (IgM). These antibodies through complement activation can cause severe, life-threatening transfusion reactions due to incompatible ABO blood transfusions. Anti-A1 antibody appears as an atypical cold agglutinin in the sera of few people with group A2 or A2B who do not have the corresponding antigen.[4] One to eight percent of persons with blood group A2 and about 22-35% of persons with group A2B have serum anti-A1. These antibodies may cause discrepancies in ABO blood grouping which can further result in HTR.[5] Rare cases of haemolytic transfusion reaction due to anti-A1 have been reported.[4] It is estimated that about 80% of individuals with antigen A are A1 while the remaining 20% are A2. [5] Among Indians, the frequency of subgroup A2 among group A individuals is 6.58% whiles that of A2B among group AB is 8.99%.[6] Knowledge of the frequency and distribution of blood subgroup A2 will help to enhance blood compatibility testing, population genetic studies, investigation of transfusion reactions, studying disease associations and resolving some medico-legal issues.[7]