Assessing the clinical efficacy of low-volume therapeutic plasma exchange in achieving recovery from acute liver failure induced by yellow phosphorous poisoning

BACKGROUND

Acute liver failure (ALF) following yellow phosphorous (YP) ingestion is similar to acetaminophen-induced ALF and it has become a public concern in our region. This study assessed low volume therapeutic plasma exchange (LV-TPE) efficacy in improving the transplant free survival in YP poisoning.

METHODS

Adult patients with toxicology reports of YP and ALF requiring critical care were included in the study. LV-TPE was planned for three consecutive days and three more if required. Performed 1.3 to 1.5 plasma volume replacing with 0.9% normal saline, 5% human albumin solution, and fresh frozen plasma based on ASFA 2019 criteria. MELD score, laboratory parameters, LV-TPE details were captured. The study end point was clinical outcome of the patients.

RESULTS

Among 36 patients, 19 underwent LV-TPE and 17 opted out of LV-TPE and they were included as a control arm. The MELD score was 32.64 ± 8.05 and 37.83 ± 9.37 in both groups. There were 13 survivors in LV-TPE group leading to a 68.42% reduction in mortality. The coagulation and biochemical parameters showed a significant percentage change after LV-TPE. Refractory shock, delay in initiating procedure and acidosis were independent predictors of mortality.

CONCLUSION

A well-timed LV-TPE improves the survival of patients with ALF due to YP poisoning.

S.O.S. - Save our supplies: Understanding reasons to tackle the challenge of wasted returned blood products

OBJECTIVES

To evaluate the return of blood components across different hospital areas, reasons for the same and suggest preventive strategies which might reduce out of controlled temperature storage (CTS) blood logistics and wastage.

MATERIAL AND METHODS

A retrospective audit was carried out in the department of Transfusion Medicine from January 2019 to December 2022. Data related to returned blood components was compiled using departmental records and blood centre software entries.

RESULTS

A total of 218 instances of returned components were noted and the total number of components returned were 442 (0.4% of all issued components) (38.4% (170) packed red blood cells, 16.2% (72) single donor cryoprecipitate concentrate, 19.6% (87) platelet concentrate and 25.5% (113) fresh frozen plasma). Components were returned back within 30 mins in only 27% (59/218) of all instances . Wards followed by high dependency units/intensive care units were noted to have the highest number of instances (86 (39.4%) and 69 (31.6%) respectively) with emergency department having the least,comprising 19 instances (8.7%). 77.9% (170/218) instances were observed for routine transfusion requests and 44.5% (97/218) of all instances could have been prevented by an appropriate clinical status assessment of the patient.

CONCLUSION

Stakeholders such as clinicians, transfusion laboratory professional and nursing staff must take consolidated efforts to eliminate wastage of blood components. Instances of returned blood components can be targeted by the hospital quality team as a quality improvement project.

Neutrophils display distinct post-translational modifications in response to varied pathological stimuli

Neutrophils play a vital role in the innate immunity by perform effector functions through phagocytosis, degranulation, and forming extracellular traps. However, over-functioning of neutrophils has been associated with sterile inflammation such as Type 2 Diabetes, atherosclerosis, cancer and autoimmune disorders. Neutrophils exhibiting phenotypical and functional heterogeneity in both homeostatic and pathological conditions suggests distinct signaling pathways are activated in disease-specific stimuli and alter neutrophil functions. Hence, we examined mass spectrometry based post-translational modifications (PTM) of neutrophil proteins in response to pathologically significant stimuli, including high glucose, homocysteine and bacterial lipopolysaccharides representing diabetes-indicator, an activator of thrombosis and pathogen-associated molecule, respectively. Our data revealed that these aforesaid stimulators differentially deamidate, citrullinate, acetylate and methylate neutrophil proteins and align to distinct biological functions associated with degranulation, platelet activation, innate immune responses and metabolic alterations. The PTM patterns in response to high glucose showed an association with neutrophils extracellular traps (NETs) formation, homocysteine induced proteins PTM associated with signaling of systemic lupus erythematosus and lipopolysaccharides induced PTMs were involved in pathways related to cardiomyopathies. Our study provides novel insights into neutrophil PTM patterns and functions in response to varied pathological stimuli, which may serve as a resource to design therapeutic strategies for the management of neutrophil-centred diseases.

I-JAMM-(I): A survey providing an insight into the practices of isoagglutinin titration in ABO incompatible kidney and liver transplantation

BACKGROUND AND OBJECTIVES

ABO-incompatible transplantations allow patients to receive timely transplants. Isoagglutinin titration to ascertain levels of incompatible antibodies in the recipient is important in determining patient selection and transplant survivability. To find out the prevalent trends in India, the largest, first of its kind survey was carried out among the transplant centers regarding their practices in isoagglutinin titration.

METHODS

The survey was drafted by a working group of Transfusion and Transplant Immunology specialists from six different centers. Data was obtained via the use of an online questionnaire.

RESULTS

Results were categorized into four categories, Hospital information, Titration methodology, Role of transfusion specialists and cut-off titers. Most centers had a well-established solid-organ transplant program with considerable number of ABO-incompatible transplantations. Most centers performed isoagglutinin titration in Transfusion Medicine department. Column Agglutination Technique (CAT) was the most common method, using EDTA blood samples and freshly-prepared in-house pooled cells. Most centers had a turn-around time of less than 12 h. While the policy for ascertaining baseline and threshold titers is well-defined in ABO-incompatible renal transplants, variations from center to center still exist for ABO-incompatible liver transplants. Most centers required a Transfusion Medicine consultation for the patients before such transplants.

CONCLUSION

With increasing ABO-incompatible kidney and liver transplants across the country, the role of Transfusion medicine specialists has become vital in pre-conditioning regimes enabling the viability and success of such transplants. This was a unique survey that provided a snapshot of current trends and practices of isoagglutinin titration for ABO-incompatible transplants in India.

Evaluating patient blood management practices using PBM metrics in a tertiary care center

BACKGROUND

PBM metrics play a crucial role in assessing and monitoring the effectiveness of PBM programs in healthcare settings. The present study aimed to assess the indicators to achieve effective enforcement of PBM at a tertiary care referral hospital.

SUBJECTS AND METHOD

A prospective observational study was conducted on patients admitted for elective surgery at a tertiary care referral centre. PBM metrics were developed and assessed for various parameters, including documentation, patient evaluation, blood ordering schedule, and appropriateness. Experts in transfusion medicine and haematology checked content validity. Eleven different parameters were analysed, and a score was assigned based on the performance. The outcome was categorized as poor, satisfactory, or good.

RESULTS

The study included 612 patients meeting the inclusion criteria and recruited from Orthopaedics, General Surgery, OBG, Urology, and ENT departments. All departments completed pre-operative anaemia tests, with General Surgery and Orthopaedics conducting the most red cell transfusions. During the study, all of the blood units were used, and there was no waste. The C/T ratio was greater in the Departments of General Surgery, Urology, and Otorhinolaryngology. Pre-operative anaemia was found in 44.12% of patients, 44 patients had red cell transfusions, with 65% getting single-unit PRBC transfusions. All departments received a PBM score between 17-19, showing adequate PBM but with room for improvement.

CONCLUSION

The current study utilized Patient Blood Management (PBM) metrics to critically assess the existing practices and identify the key gaps and areas for improvement in a tertiary care centre.

Implementation of a regional rare donor registry in India

Background

In an ethnically diverse country like India, establishing a national rare donor registry is a massive challenge. We aimed to establish a regional rare donor registry at our center by screening the local donor population for rare phenotypes.

Methods

Serological testing of O blood group donors was done using monoclonal antisera from Bio-Rad for 23 different blood group antigens, which include Rh subgroups (C,cE,e), Kell (K,k, Kpa, Kpb), P1, Duffy (Fya, Fyb), Kidd (Jka, Jkb), Lewis (Lea, Leb), Lutheran (Lua, Lub), H, M, N, S and s. We categorized the donors with rare blood phenotypes into two categories. Category-I: High-frequency antigen-negative phenotypes with a prevalence of less than 1% in our study population. Category-II: Multiple common antigen-negative phenotypes with a prevalence of less than 1% in our study population.

Results

A total of 521 donors with blood group O, meeting the inclusion criteria among a total of 23567 were phenotyped for minor blood group antigens. Out of these, 85.6% (n = 446) were Rh D positive, and 14.4% (n = 75) were Rh D negative. The male-to-female ratio was 9:1. We had identified eight rare phenotypes in category-I and 18 rare phenotypes in Category-II according to the definition adopted in our study. We have noticed a significant decrease in turnaround time in providing rare blood to patients after implementing the registry.

Conclusion

This is a first-of-its-kind rare donor registry established in South India. Establishing a national rare donor registry is the need of the hour in India.

'Ironing out the risk': Assessing the effect of plateletpheresis donation frequency on iron stores in South-Asian male donors

BACKGROUND AND OBJECTIVES

Repeated blood donation is a well-known cause of iron deficiency among donors. However, present scientific literature lacks comprehensive evidence regarding the impact of regular plateletpheresis procedures on body iron reserves. In this study, we aimed to detect and correlate iron deficiency (using iron indices) with the frequency of platelet donations. Additionally, we also analysed the correlation between other iron and haematological indices with serum ferritin to determine cost-effective parameters that may serve as an initial screening approach to determine which donors should be subjected to serum ferritin testing.

MATERIALS AND METHODS

A total of 180 male participants from our platelet donor registry were enrolled in this observational cross-sectional study. Enrolment questionnaires were administered to eligible donors, and biological samples were collected during plateletpheresis donation. Biological tests such as complete blood count, reticulocyte indices, iron indices, vitamin B12 and folate were performed.

RESULTS

Donors with ≥12 donations per year showed the highest prevalence of low ferritin (serum ferritin: 15-30 ng/mL) and absent iron stores (serum ferritin <15 ng/mL) (41.3% and 26.7%, respectively). Ferritin showed a significant negative correlation with recent (r = -0.346) and lifetime donations (r = -0.196). The efficacy of other indices for identifying iron depletion was much better using a serum ferritin value <15 ng/mL.

CONCLUSION

Regular plateletpheresis donations can lead to varying severities of non-anaemic iron deficiency. Blood centres must regularly monitor frequent plateletpheresis donors (especially donors with more than 11 donations in a calendar year) and ideally maintain their serum ferritin above 30 ng/mL.

Prevalence of blood group antigens among regular blood donors: A single center study from South India with a review of national literature

BACKGROUND AND OBJECTIVES

The antigen frequencies vary across different regions and ethnic groups. Hence, we aimed to study the prevalence of blood group antigens in our population and to systemize the zone-wise prevalence of the same across India.

MATERIALS AND METHODS

Regular voluntary O group blood donors were screened for 21 blood group antigens; C, c, E, e, K, k, Kpa, Kpb, Jka, Jkb, Fya, Fyb, Lea, Leb, Lua, Lub, P1, M, N, S, s, using commercially available monoclonal antisera by column agglutination technology. A literature search was performed to identify all the studies that reported blood group antigens prevalence to estimate the zone-wise prevalence of these antigens in the country.

RESULTS

A total of 521 participants of 9248 O group donors meeting all the inclusion criteria were included. Among the study group, the male-to-female ratio was 9:1 with a mean age of 32.6 years (±10.01) ranging from 18-60 years. The majority of the donors 446 (85.6%) were D positive. The most common phenotypes among Rh, Lewis, Kell, Duffy, Kidd, Lutheran and MNSs were CcDee (34.93%), Le(a-b+) (61.80%), K-k+(98.27%), Fy(a+b-) 43.19%, Jk(a+b+) 42.61%, Lu(a-b+) ( 99.61%), M+N+ (48.17%), S-s+ (45.29%) respectively. The prevalence of D and E antigens was significantly lower in the South zone compared to other zones of India.

CONCLUSION

Significant difference in the prevalence of blood group antigens is observed between the South and other zones of India. Zone-wise prevalence of blood group phenotypes is essential in the timely management of alloimmunized patients.

A survey on insight of blood donors during COVID pandemic in Southern India

INTRODUCTION

Knowledge, Attitude and Practices (KAP) surveys prove beneficial to the transfusion services by providing an insight into the donors and, thus, aiding in mobilizing and retaining voluntary blood donors. We aim to study the knowledge, attitude and practices of donors towards blood donation in a pandemic setting.

METHODS

A cross-sectional observational study to assess the knowledge, attitude and practices of blood donors was conducted between June to and October 2020. Non-parametric tests (Mann - Whitney U and Kruskal - Wallis) were performed to evaluate the relation of knowledge, attitude and practices overall scores with age group, gender and history of blood donations (first vs. repeat). The Chi-Square test/Fisher's Exact test was used to evaluate the differences in the distribution of Knowledge, Attitude and Practices items within the groups.

RESULTS

A total of 403 of 2,748 individuals who came for whole blood donation participated in the study. The mean age of the study population was 31.1years (SD ± 8.4 range: 18 - 58), with 75% of the donors donating for the first time. The fear of acquiring COVID-19 infection was perceived as a major reason for the eligible population not to donate. The overall knowledge, attitude and practice score among the donors was satisfactory, being 76.14%, with a significant association with age. The overall positive attitude and practices scores of blood donors were 85.48% and 78.04%, respectively.

CONCLUSION

The KAP scores were satisfactory among the donors. Timely communication of the precautionary measures at blood centers to contain the spread of the COVID-19 infection and effective counseling would help in motivating and retaining blood donors.

A case report and review of literature on the role of automated red cell exchange in managing sickle cell crisis in India

Red cell exchanges (RCE) help in the treatment of complications of sickle cell anemia (SCA) by reducing the viscosity of blood and improving the oxygen-carrying capacity. We present a case of sickle cell crisis (SCC) managed with automated RCE and also reviewed the literature to assess the utilization and clinical efficiency of this therapy in India. A 19-year-old gentleman diagnosed with SCA presented with acute chest syndrome. Hemoglobin (Hb) was 8.8 g%, hematocrit (HCT) was 24%, and HbS was 90%. As there was worsening of symptoms with conventional management, the patient underwent two procedures of automated RCE. The clinical condition of the patient was improved, HbS was reduced to 16% and HCT was remained at 21% postprocedure. Articles on automated RCE in SCA conducted in India were reviewed and four articles were analyzed based on the search strategy. All the included articles concluded automated RCE as an effective procedure for complications of SCA. Common indication in India was SCA patients undergoing surgery as a prophylactic measure. Automated RCEs are promising as an acute treatment for indicated sickle cell complications. This therapy is underutilized in the Indian scenario, especially in patients with SCC.

Real-world data from India on clinical practices in the management of autoimmune haemolytic anaemia: A survey-based cross-sectional assessment

BACKGROUND

Autoimmune haemolytic anaemia (AIHA) is a decompensated acquired haemolysis caused by the host's immune system acting against its own red cell antigens. The aim of this national survey is to capture real-world data of clinical practices in AIHA by collecting responses from clinical haematologists across India.

METHODOLOGY

In this cross-sectional study, a structured, 26-question online survey was conducted in India by few members of the special interest group in immunohaematology between January and March, 2022. The final survey consisted of questions covering place of work, amount of AIHA cases being evaluated by the haematologist over preceding years, basic demographic, clinical and laboratory features of the patients being treated under them etc. Descriptive statistical analysis was performed during the assessment.

RESULTS

The survey response rate was 48.2% (53/110), 69.8% (37/53) have diagnosed and managed more than 10 AIHA cases in the last 3 years with a female preponderance. There was considerable variability in response. While 56.6% (30/53) of respondents do have the access to the facilities to subtype AIHA cases; 32.1% (17/53) of clinicians would prefer administering high dose steroids for 6 weeks or more in non-responding patients, and only 45.3% (24/53) would assess the risks of thrombosis in AIHA. There is unanimous agreement among the participants that health-related quality of life should be taken into consideration in patients and the need for a national registry of patients with AIHA in India.

CONCLUSION

The current national survey showed that some aspects of AIHA management were consistent; others were less so, but also significant variations were observed in certain clinical practices, where the evidence base is limited. A joint effort is needed to establish a national patient registry by including both clinical haematologists and transfusion medicine specialists which could potentially standardise AIHA management and future research in India.

Role of Thromboelastogram in monitoring the activation of the coagulation pathway and assessing the associated risk factors for hypercoagulable state in transfusion dependent thalassemia patients

BACKGROUND

Thromboembolic events are rare but one of the fatal complications in thalassemia. Assessment of the hypercoagulable state is not done regularly, and we have assessed the utility of Thromboelastography (TEG) for monitoring the activation of the coagulation pathway in patients with thalassemia.

METHODOLOGY

A prospective single-center cohort study was conducted in a tertiary care set-up. Transfusion Dependent Thalassemia patients registered with the pediatric unit were screened for hypercoagulability using TEG during six months of the study period and followed up for three years for the development of thromboembolic events. Patient demographics, history of splenectomy, Serum ferritin levels and annual red cell transfusion requirement (mL/kg/year) were assessed. TEG parameters used were R time, K time, alpha angle, Maximum amplitude, Clot index, and Lysis 30. The thrombin generation test (V Curve) obtained from the first-degree derivate of the TEG velocity curve was also used for analysis.

RESULTS

A total of 34 patients were recruited during the six months study period with an average age of 10.6 years ( ± 5.47). The average pre-transfusion hemoglobin level and the volume of packed red cells received were 7.24 g/dL and 152.82 mL/kg/year respectively. The TEG tracing was suggestive of a hypercoagulable state in 58.82% of patients. The mean values of angle (70.74), MA (64.16), CI (2.65) and TG (774.43) in TDT patients compared to age matched reference range (62.81, 57.99, 0.8, 577.83 respectively) was suggestive of prothrombotic changes. Annual blood transfusion requirement was negatively correlated with hypercoagulable status (-0.344, CI= -0.68 to 0.08). One out of 34 patients developed corona radiata infarct (with annual blood requirement; 112.7 mL/kg/Year). The risk to develop a hypercoagulable state appeared to be higher when the volume of RBCs transfused was less than 154 mL/kg/Year.

CONCLUSION

TDT patients are at risk of developing thromboembolism, and screening with TEG may be useful to identify those at high risk.

Efficacy of cascade plasmapheresis in comparison with conventional therapeutic plasma exchange for relapsed atypical hemolytic uremic syndrome: A case report

Atypical hemolytic uremic syndrome (aHUS) is a rare and life-threatening disease that is associated with high mortality and morbidity. The incidence of aHUS is about 1 or 2 cases per 1,000,000 per year. Etiology can be either familial or sporadic. The pathogenesis of aHUS involves dysregulation of the alternative complement pathway, with predisposing mutations in complement genes. aHUS has a poor prognosis and a gradual or a relapsing (30%-86%) clinical course. The disease may present at any age but is mostly seen in children and young adults. Therapeutic plasma exchange (TPE) is one of the primary modalities of treatment in aHUS. This report presents the utilization of cascade plasmapheresis and its advantages over TPE in a patient with relapsed aHUS. There was a 73% decrement in antifactor H antibody levels following cascade plasmapheresis.

ADAMTS13 factor deficiency in severe COVID-19 may not be immune mediated-report from a pilot study

BACKGROUND

The assessment of ADAMTS13 factor activity and inhibitor levels was conducted in severe COVID-19 patients as an observational study.

RESULTS

A total of 14 patients were included and the average ADAMTS13 activity level at the time of admission was 28.54±30.74% (range 1.83-86.67%) which was reduced compared to controls (88.09±14.77). Nine patients had reduced ADAMTS13 factor activity (<40%) and 77.7% among them had severe deficiency (<10% activity). ADAMTS13 inhibitor was positive (>15 IU/mL) only in two patients and an overall mean value was 8.15±5.8. Elevated D-Dimer and length of hospital stay had significant correlation with ADAMTS13 activity (-0.247 and 0.306 respectively). No features of thrombotic microangiopathy were observed and hence no plasma exchange was performed.

CONCLUSION

Reduced ADAMTS13 factor activity without inhibitor development may give a clue to the disease progress in COVID19.

Quantitative phosphoproteomics reveals diverse stimuli activate distinct signaling pathways during neutrophil activation

Neutrophils display functional heterogeneity upon responding diversely to physiological and pathological stimulations. During type 2 diabetes (T2D), hyperglycemia constitutively activates neutrophils, leading to reduced response to infections and on the other hand, elevated metabolic intermediates such as homocysteine induce bidirectional activation of platelets and neutrophils leading to thrombosis. Hence, in the context of T2D-associated complications, we examined the influence of high glucose, homocysteine, and LPS representing effector molecules of hyperglycemia, thrombosis, and infection, respectively, on human neutrophil activation to identify distinct signaling pathways by quantitative phosphoproteomics approach. High glucose activated C-Jun-N-Terminal Kinase, NTRK1, SYK, and PRKACA kinases associated with Rho GTPase signaling and phagocytosis, whereas LPS induced AKT1, SRPK2, CSNK2A1, and TTN kinases involved in cytokine signaling and inflammatory response. Homocysteine treatment led to activatation of  LRRK2, FGR, MAPK3, and PRKCD kinases which are associated with neutrophil degranulation and cytoskeletal remodeling. Diverse inducers differentially modulated phosphorylation of proteins associated with neutrophil functions such as oxidative burst, degranulation, extracellular traps, and phagocytosis. Further validation of phosphoproteomics data on selected kinases revealed neutrophils pre-cultured under high glucose showed impeded response to LPS to phosphorylate p-ERK1/2^{Thr202/Tyr204}, p-AKT^Ser473, and C-Jun-N-Terminal Kinase^Ser63 kinases. Our study provides novel phosphoproteome signatures that may be explored to understand neutrophil biology in T2D-associated complications.

Utility of Thromboelastography and velocity curve derivative in diagnosing COVID-19 associated coagulopathy

Background

COVID‐19 associated coagulopathy (CAC) can either be localized or systemic hypercoagulable state with increased risk of thromboembolism. This study looked into the usefulness of Thromboelastography (TEG) and the velocity curve (V‐curve) derivative from TEG in diagnosing and differentiating different stages of CAC.

Materials and Methods

A prospective single cohort study of RT‐PCR confirmed COVID‐19 patients was carried out for 2 weeks. Severe COVID‐19 patients in the adult critical care units with a TEG report were recruited for the study. Citrated kaolin TEG was performed on the day of admission before anticoagulation. TEG parameters included were R and K time, alpha angle, maximum amplitude, clotting index, lysis at 30 min. The first‐degree velocity curve of TEG is plotted as V‐curve which extrapolates thrombus generation potential. Parameters analyzed were the maximum rate of thrombus generation as well as thrombus generated (TG).

Results

The study included 43 patients with an average age of 58.34 (±15.35). TEG as well as V‐curve of all the patients were hypercoagulable compared with age‐matched reference range. We had 79.06% of patients in hypercoagulable stage. The mortality rate was 32.56% and 30.23% developed thrombotic incidents. Patients who succumbed to death had prolonged PT, aPTT, MA, Ly30, with a reduced TG (p < .05). The presence of fibrinolysis was associated with thromboembolism (OR = 6.76, CI = 1.48–25.82). Repeat TEG was done randomly in 11 patients and revealed a persistent hypercoagulable stage with increasing fibrinolysis activity.

Conclusion

TEG is a useful tool in diagnosing and categorizing Coagulopathy associated with COVID‐19.

Reverse Algorithm Screening of Syphilis and trends in prevalence among Blood Donors in Coastal Karnataka

BACKGROUND

Transfusion transmissible syphilis is caused by Treponema pallidum; blood donors are traditionally screened with non-treponemal antibody tests to ensure transfusion safety. Detection of specific antibodies against T.pallidum is employed in reverse algorithm screening. We aim to analyze the utility of reverse algorithm screening strategy for T.pallidum and to determine the prevalence trends among blood donors in our centre.

MATERIAL AND METHODS

The study was conducted in a Transfusion Centre catering 2030 bedded Tertiary Care Centre in coastal Karnataka in two timelines from 2012 to 2014, and 2019 to 2020, respectively. A fully automated Enzyme-Linked Immunosorbent Assay and Enhanced Chemiluminescence Immunoassay, which detect both IgM and IgG antibodies against T. pallidum were used in the study. Blood donor's data from 2008 to 2020 were also analyzed to observe the prevalence trends of syphilis among blood donors.

RESULTS

Among 26329 and 388 blood donors screened with ELISA and ECI, 134 (0.51%) and 9 (2.3%) were reactive to T.pallidum antibodies respectively. TPHA confirmed 104 and 9 donors reactive from each of ELISA and ECI reactive donors. The increase in the prevalence of syphilis was observed with the utility of treponemal screening compared to the traditional strategy. The prevalence ranged from 0.02 to 0.28%.

CONCLUSION

The reverse algorithm screening can give a sensitive result compared to the gold standard with 77.61% and 88.9% predictability of true positive for ELISA and ECI. Our study found that the utility of reverse algorithm though mildly increases the discard rate but ensures blood safety to a greater extent.

Red blood cell alloimmunization among recipients of blood transfusion in India: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

There is a varied prevalence of red cell alloimmunization being reported from different parts of India. This study aimed to estimate the overall prevalence of alloimmunization in India by performing a systematic review of the literature and to establish the most suitable antigen-matching strategy to reduce the red blood cell (RBC) alloimmunization rate among transfusion recipients.

MATERIALS AND METHODS

A systematic search of all the original articles published in English on RBC alloimmunization among transfusion recipients from India in MEDLINE, SCOPUS, CINAHL and Google Scholar bibliographic databases was conducted. After screening the articles as per inclusion/exclusion criteria, data extraction was done independently by two sets of investigators. Meta-analysis was performed by the binary random-effects model using the restricted maximum likelihood method.

RESULTS

A total of 44 studies on RBC alloimmunization, with a cumulative sample size of 309,986 patients, were grouped into hospital-based and multiply-transfused patients, which yielded a prevalence of 0.5 (95% confidence interval; 0.3-0.8) and 4.8 (95% confidence interval; 3.9-5.7) per 100 patients, respectively. As many as 1992 alloantibodies were identified among the 1846 alloimmunized patients. The most common antibody identified was anti-E (127; 31.99%), followed by anti-c (75; 18.89%) in multiply-transfused patients.

CONCLUSION

The rate of alloimmunization was 0.5 per 100 patients tested for antibodies and 4.8 per 100 patients receiving transfusion. Considering E- and c-antigen-matched red cells along with ABO and RhD matching may significantly reduce the overall occurrence of alloimmunization among Indian population who are transfusion-dependent.

Nanoporous and nano thickness film-forming bioactive composition for biomedical applications

Unmanageable bleeding is one of the significant causes of mortality. Attaining rapid hemostasis ensures subject survivability as a first aid during combats, road accidents, surgeries that reduce mortality. Nanoporous fibers reinforced composite scaffold (NFRCS) developed by a simple hemostatic film-forming composition (HFFC) (as a continuous phase) can trigger and intensify hemostasis. NFRCS developed was based on the dragonfly wing structure's structural design. Dragonfly wing structure consists of cross-veins and longitudinal wing veins inter-connected with wing membrane to maintain the microstructural integrity. The HFFC uniformly surface coats the fibers with nano thickness film and interconnects the randomly distributed cotton gauge (Ct) (dispersed phase), resulting in the formation of a nanoporous structure. Integrating continuous and dispersed phases reduce the product cost by ten times that of marketed products. The modified NFRCS (tampon or wrist band) can be used for various biomedical applications. The in vivo studies conclude that the developed Cp NFRCS triggers and intensifies the coagulation process at the application site. The NFRCS could regulate the microenvironment and act at the cellular level due to its nanoporous structure, which resulted in better wound healing in the excision wound model.

Illustration: Thromboelastography – A useful tool to monitor COVID-19-associated coagulopathy

COVID 19 is caused by Severe Acute Respiratory Syndrome Corona Virus-2 which results in wide range of manifestations. Systemic hypercoagulation is a typical feature of COVID-19. We present a case of COVID-19 in whom TEG was performed on admission and hypercoagulability was diagnosed and hence patient was started on Enoxaparin sodium 6000 IU twice daily. TEG was repeated after 5 days which showed normal coagulation status and the patient was discharged without any thrombotic complications.

COVID-19 pandemic and blood transfusion services: The impact, response and preparedness experience of a tertiary care Blood Center in southern Karnataka, India

Introduction

With the outbreak of COVID-19 and its containment measures, blood centers faced a huge challenge in balancing blood demand and supply and devising a preparedness plan to withstand the uncertain situation. This study assesses the effect of the COVID-19 pandemic on blood transfusion services and discusses the appropriate mitigation strategies adopted.

Methods

We analyzed our center's blood transfusion services during the first half-period of the pandemic (Y3) and non-pandemic years 2018(Y1) and 2019(Y2) in two-quarters Q1 (pre-lockdown), from January to March and Q2 (post-lockdown), from April to June. The blood donation variables, the packed red blood cells (PRBCs) demand and the utilization pattern were compared between pandemic (Y3) and non-pandemic years (Y1 and Y2) in each quarter. The mitigation strategy adopted at every step of the transfusion service is highlighted.

Results

During post-lockdown (Q2) of the pandemic year (Y3), the blood donation was majorly by repeat donors (83%) from the in-house site (82.5%). Furthermore, the proportion of outdoor donation, deferral, blood collection, demand and issue demonstrated a significant drop of 50%, 32.6%, 33%, 31.8% and 32.3%, respectively, in comparison to Q2 of the non-pandemic years (Y1 and Y2), with a statistically significant difference for surgical and hemorrhagic indications (p < 0.05). Coping strategies, such as blood donor education and motivation using e-platforms emphasizing eligibility during the pandemic, staggering of donor in-flow, postponement of elective surgeries and donor and staff’ COVID-19 safety assurance, were followed.

Conclusion

The timely adoption of coping strategies played a crucial role in the better handling of shortcomings at our center's blood transfusion services caused by the COVID-19 pandemic.

A Tropical Kiss by a Malabar Pit Viper

Snakebite in India is often attributed to the "big 4," for which polyvalent anti-snake venom is effective. Also significant and less known is the burden of other venomous snakes, one of which is Trimeresurus malabaricus. We report a bite to the face of a tree climber by Trimeresurus malabaricus in the Western Ghats of India, which caused severe local envenomation in the form of facial edema and systemic signs of envenomation, including coagulopathy and hypotension. We discuss the role of thromboelastogram, infrared thermography, and routine diagnostics in this case, which led to the administration of Indian-made polyvalent anti-snake venom. The patient recovered and was discharged without any clinically evident physiological or physical dysfunction.

The role of thrombocytapheresis in the management of extreme thrombocytosis: a 6 years’ experience from a tertiary care center

Background. According to the American Society for Apheresis (ASFA) guidelines, thrombocytapheresis is a Category II indication in symptomatic patients and is a Category III indication when used as secondary or prophylactic treatment. The role of thrombocytapheresis is to prevent untoward complications that might occur even before the cytoreductive agents can exert their action. Methods. A retrospective analysis of patients who underwent thrombocytapheresis between 2012 to 2018 was conducted. Demographic details, complete blood counts, diagnosis and indication for thrombocytapheresis were noted. Results. A total of 12 patients with thrombocytosis were included in the study. The cause of thrombocytosis was primary in 3 (25%) patients and secondary in 9 (75%) patients. The average percentage reduction in platelet count was 47.1% (range 12.3%-65.64%). There was a significant decrease in platelet count, platelet crit, and mean platelet volume after the procedure when compared to pre-procedure. Conclusion. Thrombocytapheresis selectively reduces platelet counts with no effect on other cellular and plasma components. The role of thrombocytapheresis in extreme thrombocytosis is to be considered for an immediate decrease in platelet count and to minimize the risks associated with thrombocytosis.

Variable reactivity of Rh D antigen and its serological characterization

Background: Variation in the reactivity on Rh D typing may pose challenges in interpretation and ambiguity in further patient management.Materials and Methods: A prospective study was conducted in the department of transfusion medicine for a period of 18 months. Blood grouping was performed by fully automated equipment employing column agglutination technique. All the samples with Rh D negative or discrepant reactions were subjected to weak D testing by the antihuman globulin testing method. Samples that tested positive were categorized as serological weak D type or Variant D and were further phenotyped with Partial D typing set with 6 monoclonal anti D antisera.Results: A total of 82,824 samples were tested for Rh D type during the study period. Of the study population, 65.7% were males. On Rh D type majority were Rh D positive (93%), 6.9% were negative, and the result was discrepant in 0.1% (70) samples. The overall prevalence of variant D was 1.28% (75) of the Rh D negative population and 0.09% of the total study population. The detection rate of variant D phenotype was significantly higher by the Column agglutination technique. Upon testing with Partial D kit, the partial D variant in the majority reacted wil all the 6 antisera and hence we could not rule out DIII(60%), in rest it was inconclusive. In 43% of subjects with Rh D discrepancy 'C' antigen was found in a homozygous state.Conclusion: The introduction of partial D typing kit alone may not help in the absolute characterization of variant D. Extended serological testing and selective integration of molecular testing is the need of the hour.

Single cell spectroscopy of red blood cells in intravenous crystalloid fluids

Crystalloid fluids, a subset of intravenous (IV) fluid solutions are commonly used in clinical settings. The influence of these fluids on the functions of blood components are least explored. Raman spectroscopy combined with optical trapping has been widely used to evaluate the impact of external stress agents on red blood cells. The present study investigates the impact of commonly used crystalloid fluids on red blood cells in comparison with that of blood plasma using Raman Tweezers spectroscopy. The red blood cells suspended in crystalloid fluids undergo deoxygenation readily than that in blood plasma. In addition, cells in blood plasma were able to withstand laser induced deoxygenation comparatively better than that in crystalloid fluids at higher laser powers. Principle component analysis of the Raman spectral data has clearly demonstrated the discrimination of cells in plasma with that of crystalloid fluids demonstrating the effect of external induced stress on RBCs.

Evaluation and monitoring of response to platelet transfusion therapy: experience from a tertiary care center

Objective: Refractoriness to platelet transfusion is defined as Corrected Count Increment (CCI) <5000 after two sequential ABO identical transfusions. Immune causes include alloimmunization to HLA and/or platelet-specific antigens. Analysis of various factors leading to platelet refractoriness would help in the management of the patient in a timely manner.Materials and Methods: A prospective observational study on platelet transfusions from November 2013 to June 2015 was conducted. Demographic information, pre, and post-transfusion platelet counts and relevant clinical details were noted. Among patients who were considered refractory to platelet transfusions, platelet factor 3 assay was performed to detect antiplatelet antibodies. Data were analyzed using SPSS software. A P value of <0.05 was considered to be statistically significant.Results: A total of 1190 patients received platelet transfusions during the study period. Among these only 339 (28.5%) patients received transfusions on two or more occasions, of which 237 (69.91%) were considered non-refractory. Among the 102 (30.1%) refractory cases non-immune causes for refractoriness were present in 97 (95.1%) patients and antiplatelet antibody was positive in 18 (17.64%) patients. Bleeding and medication have shown to have significantly contributed to refractoriness (p = 0.025 and 0.003) respectively. Use of medication was independently associated with refractoriness.Conclusion: Non-immune causes are more profound in leading to a poor response to platelet transfusions. Recognizing the cause of poor response and treating the underlying cause would help in getting a better response.

Use of platelet components: An observational audit at a tertiary care centre

Background Platelets should be transfused appropriately, based on the cause of thrombocytopenia. The practice and policies of transfusion vary among institutions and even among clinical practitioners, leading to inappropriate use of platelets, which might increase the risk of transfusion-related complications to recipients, and lead to a shortage of platelets. An audit of platelet components helps to determine the effectiveness and appropriateness of their use and in improving transfusion practices. We did an audit of the use of platelet transfusions at our centre. Methods We conducted a prospective concurrent audit of the platelet transfusion practices. The audit cycle had four steps: (i) defining the standards; (ii) data collection; (iii) comparison against the standards; and (iv) presenting them to clinicians for further improvement. Results Platelet components were used appropriately in 93.6% (2420/2586) of episodes. The platelet count was not done before transfusion in only 6.4% (165/2586) of episodes. The dose of platelets was given appropriately in 84.3% (2180) of episodes of transfusion. Indications for appropriate transfusion classified as pre-procedure, prophylactic and therapeutic transfusions were 11.3% (293), 66.1% (1450) and 13% (412), respectively. Medicine and medical oncology were the specialties with the highest level of appropriateness. Conclusion An audit of transfusion practices benefits transfusion services and clinicians in terms of judicious use of platelet components and better inventory management.

Neonatal testing leading to the identification of Bh (para-Bombay) phenotype in the mother: case report with review of the literature

Para-Bombay is a rare phenotype with a homozygous nonfunctional FUT1 gene and a normal FUT2 gene leading to H-deficient red blood cells (RBCs) with or without ABH substances, depending on inheritance of the ABO gene. This case is about a 5-day-old male baby suffering from sepsis who required a 45-mL packed RBC transfusion. The baby's sample tested as A₁B, D+ and mother's sample tested as group O, D+ with group 4 discrepancy due to ABO isoagglutinins. Further workup of the mother's sample with anti-H lectin was negative, which suggested the mother to be group O_h, D+. Antibody screening was panreactive with negative autocontrol, suggestive of anti-H. The titer of immunoglobulin (Ig)M anti-H was 64, IgG titer using dithiothreitol was 8, and anti-IH was absent. A negative adsorption and elution test suggested that RBCs were devoid of A and B antigens. The father's sample tested clearly as group A₁, D+; hence, the cis-AB blood group was ruled out in the baby. The secretor study of the mother's saliva revealed the presence of B and H substances that neutralized polyclonal B and H antisera. Therefore, we concluded that the mother was of the para-Bombay (B_h) phenotype. This case highlights the importance of reverse grouping and resolving blood grouping discrepancies between mother and child-in this case because of an incongruous ABO blood type of the baby and the mother who was previously tested as group O, D+.

Para-Bombay is a rare phenotype with a homozygous nonfunctional FUT1 gene and a normal FUT2 gene leading to H-deficient red blood cells (RBCs) with or without ABH substances, depending on inheritance of the ABO gene. This case is about a 5-day-old male baby suffering from sepsis who required a 45-mL packed RBC transfusion. The baby’s sample tested as A₁B, D+ and mother’s sample tested as group O, D+ with group 4 discrepancy due to ABO isoagglutinins. Further workup of the mother’s sample with anti-H lectin was negative, which suggested the mother to be group O_h, D+. Antibody screening was panreactive with negative autocontrol, suggestive of anti-H. The titer of immunoglobulin (Ig)M anti-H was 64, IgG titer using dithiothreitol was 8, and anti-IH was absent. A negative adsorption and elution test suggested that RBCs were devoid of A and B antigens. The father’s sample tested clearly as group A₁, D+; hence, the cis-AB blood group was ruled out in the baby. The secretor study of the mother’s saliva revealed the presence of B and H substances that neutralized polyclonal B and H antisera. Therefore, we concluded that the mother was of the para-Bombay (B_h) phenotype. This case highlights the importance of reverse grouping and resolving blood grouping discrepancies between mother and child―in this case because of an incongruous ABO blood type of the baby and the mother who was previously tested as group O, D+.

Naturally occurring anti-Kpa in an infant with recurrent bacterial infection: A case report and review of the literature

Naturally occurring anti-Kp^a antibody is extremely rare and was first reported in 1957, named after the first producer 'Penney'. However, the subsequent anti-Kp^a reports presented were all anti-Kp^a due to isoimmunization. Individuals with severe bacterial infections particularly Gram-negative bacteria are known to be capable of producing cross-reactive antibodies against Kell blood group system. However, such uncommon antibodies like anti-Kp^a can be easily missed in routine pre-transfusion testing unless the panel cells containing low incidence antigen are used for antibody screening. Here, we report a case of naturally occurring anti-Kp^a antibody, identified incidentally during pre-transfusion testing of a 12-month-old female infant with the diagnosis of Niemann-Pick disease and recurrent bacterial (Escherichia coli) infection.

Molecular characterization of RhD variant phenotypes among blood donors: A study from the coastal region of India

BACKGROUND

RhD expression varies with population and ethnicity. Accurate typing of RhD antigen among blood donors is important to prevent development of anti-D among recipients of blood transfusion. We aimed to screen blood donors for variant D phenotypes and accurately characterize them by genotyping.

MATERIAL AND METHODS

We have done prospective study on blood donors by performing RhD typing using three different commercial monoclonal anti-D reagents by both column agglutination and conventional tube techniques. Samples that showed ambiguous results were further screened with the Bio-Rad Partial RhD typing kit. Minor phenotyping for C, c, E, e antigens was performed. Multiplex PCR and Sequencing of all RHD exons with Sanger's sequencing was performed for molecular characterization of variant D.

RESULTS

A total of 16,974 blood donors were screened during the study period. Among them, 31 (0.18 %) donors were found to have a RhD variant phenotype. The male to female ratio was 10:1. The presence of 'C' antigen was noted among all RhD variant samples. Serological typing identified two samples as DV phenotype and the rest could not be characterized. Molecular genotyping characterized 90.3 % of the samples as Indian specific weak D type 150 variants. Three samples were subjected to Sangers sequencing and showed wild type pattern.

CONCLUSION

The present study showed that the most common variant in this population was Weak D type 150. This study highlights that serological methods may serve as a screening tool, however, molecular techniques are essential for characterization of RhD variants.

Transfusion requirement prediction score for patients undergoing cardiac surgery: An experience from a tertiary care set-up from South India

BACKGROUND

Prediction of transfusion requirement is part of preoperative management in a surgical case. We aimed to develop one such tool for patients undergoing cardiac surgery.

METHODS

A retrospective study for a period of 3 years was done to develop the scoring tool, Transfusion Requirement Prediction Score for Cardiac Surgery (TRPS), and internal validation was done prospectively. The primary outcome was administration of allogenic red cell units to the patients during perioperative period. The outcome is dichotomized as controls and cases based on the number of Red Blood Cell units received. Independent variables were chosen based on statistical significance and clinical judgement. Receiver operating characteristic curve was used to obtain the cut-off for each independent variable, odds ratio, and regression coefficients were used to assign the score. All patients with a cumulative score below the cut-off value were categorised as 'low risk' and above the cut off as 'high risk' group.

RESULTS

During the study period, out of 602 patients, 345 met the inclusion criteria (controls: 175; cases: 170). Six variables such as age (more than 58 years), gender (female), bypass time (more than 148 min), haemoglobin (less than 12.5 g/dL), ejection fraction (less than 57%), and history of warfarin prophylaxis were chosen to develop the score. The total score value of 5 was chosen as the cut-off for the two risk groups. It predicted blood utilisation with a strength of 68% sensitivity and 79% specificity. On internal validation, the score was observed to have an accuracy of 70%.

CONCLUSION

The TRPS is a simple reliable and handy tool with high accuracy.

Cocktail Protocol for Preparation of Platelet-Rich Fibrin Glue for Autologous Use

Background

Biomaterials containing platelets have been used to promote healing of ulcers and burns, as well as in implantology and maxillofacial and plastic surgery to achieve wound healing and tissue repair. Commercial devices to prepare autologous biomaterials involve diverse preparation methods that can have high production costs and low yields. Hence, we designed a protocol for preparation of large amounts of autologous platelet-rich fibrin (PRF) glue using conventional processing techniques for blood components.

Methods

Autologous whole blood collected 72 h before surgery was processed to prepare platelet concentrates and cryoprecipitate. In a closed system, calcium was added to the cryoprecipitate to release autologous thrombin and generate a firm fibrin clot. The fibrin clot, platelets and calcium were then placed in a conical flask in which a PRF glue formed. The protocol was validated through determination of pre- and post-platelet counts and fibrinogen amounts in the product.

Results

Platelets were recovered with 68% efficiency during the preparation. Essentially no platelets or fibrinogen were found in the supernatant of the PRF glue, suggesting that nearly all had been incorporated in a PRF glue having a relatively large (8 cm × 10 cm) size.

Conclusion

The protocol described here is a cost-effective, simple and closed system that can be used to produce large-size PRF glue to promote repair of major surgical defects.

Frequency and clinical significance of red cell antibodies in pregnancy - A prospective study from India

Background

For appropriate management of hemolytic disease of the fetus and newborn (HDFN), it is important to detect irregular red cell antibody in the antenatal period. Though it is a simple one-step method, it is not part of routine antenatal screening in many developing countries. To reiterate the importance of antenatal antibody screening, we have assessed the frequency and clinical significance of irregular red cell antibodies in our patient population.

Materials and Methods

A prospective study was carried out from October 2013 to May 2015 at a tertiary care center from south India. All antenatal samples received by the laboratory for red cell antibody screening were screened using a commercial three-cell screening panel. Antibody identification along with further Immunohematological techniques as required were performed for cases with positive screening results. Neonates of the alloimmunized cases were followed up to determine the clinical significance of the antibody.

Results

A total of 2336 antenatal mothers were screened for red cell antibodies. The overall rate of alloimmunization in the study group was 2.27%. Alloimmunization rate among RhD-negative pregnancies was 6.9%. Other than anti-D (49%), we identified anti-D + anti-C (5%), anti-G (5%), anti-c (5%), anti-E (2%), anti-e (2%), anti-H (Bombay phenotype) (7%), anti-M (2%), anti-Lea (2%), anti-Leb (12%), and autoantibodies (9%) in the maternal serum. Anti-D, anti-D + anti-C, anti-G, anti-c, and anti-H were found to be clinically significant in this study.

Conclusion

This study showed that 1 in 125 RhD-positive pregnancies can develop red cell alloantibodies. Hence, implementing routine antenatal antibody screening irrespective of RhD status is essential.

Passenger lymphocyte syndrome in a bidirectional ABO-mismatched renal transplant

Passenger lymphocyte syndrome (PLS), a subtype of graft-versus-host disease, is due to the production of antibodies by the donor “passenger” B lymphocytes against recipient's red cells. It is a rare disorder encountered mostly in ABO blood group-mismatched solid organ transplantation. The present case report illustrates the clinical presentation and the mode of management of PLS in a bidirectional ABO-incompatible renal transplantation. A 43-year-old male diagnosed with chronic kidney disease Stage 5-D (diabetic nephropathy) Type-2 hypertension with ischemic heart disease underwent ABO bidirectional-mismatched renal transplantation. The blood group of the patient was B Rh D positive and that of the donor (patient's wife) was A Rh D positive. In the pretransplantation phase, immunoglobulin G anti-A titer was 64 by column agglutination method, which was subsequently brought down to 4 by therapeutic plasma exchange and immunosuppression. Good graft function was established in the posttransplantation phase, but a significant drop in the hemoglobin (Hb) was noted. A fall in Hb, peripheral smear findings suggestive of hemolysis, and direct antiglobulin test positivity along with raised lactate dehydrogenase suggested the diagnosis of PLS; the patient was managed successfully for the same by transfusion of O blood group packed red blood cell transfusion and immunosuppression. PLS is a rare but important cause of immune-mediated hemolytic anemia in ABO-mismatched transplants.

Blood Donor Deferral Analysis in Relation to the Screening Process: A Single-Center Study from Southern India with Emphasis on High Hemoglobin Prevalence

Purpose

Donor deferral results in loss of potential, motivated blood donors, and thereby, availability of blood for needy patients. This study analyses the frequency and reasons for donor deferral, including high hemoglobin deferral, which is underreported in India.

Methods

Retrospective analysis of the deferral record of whole blood donors from January 2014 to December 2018 was performed with respect to the pre-donation screening process at our center. Accordingly, the deferrals are categorized as stage1 – evaluation of Donor History Questionnaire (DHQ), stage 2 – medical examination, stage 3 – hemoglobin (Hb) check using copper sulfate method or a gradually implemented quantitative hemoglobin analyzer, and stage 4 – before phlebotomy. Donor demographic details, donation frequency, and deferral reasons were noted. Descriptive statistical analysis was performed using SPSS version 20 (IBM, USA).

Results

Of 99,680 pre-donation screenings, 10.6% was deferred. The highest deferral (56.02%) was at stage 3 (based on hemoglobin level) contributed by low (52.45%) and high (3.75%) hemoglobin deferrals against cut-off of 12.5 to 18 g/dl. High Hb was noted only in male donors when screened by hemoglobin analyzer. Further, a steady fall in low hemoglobin but a rise in high hemoglobin deferral rate owing to the gradual implementation of hemoglobin analyzer over the study period was noted. The deferrals in stage 1, 2, and 4 were 29.64%, 13.97%, and 0.36%, respectively. Overall, the deferral rate was higher in females (49.88%), and in first-time (13.63%), and 18 to 25 yrs age-group (4.25%) donors for low Hb, underweight, and tattooing/ear piercing.

Conclusion

Insights on donor deferral reasons promote proactive measures towards donor recruitment and retention. Further, donor hemoglobin screening by quantitative method, if followed uniformly by all blood centers across the country, will help identify the true prevalence of high hemoglobin in Indian blood donors and ensures donor safety.

Clinical Implication of Immunohaematological Tests in ABO haemolytic disease of newborn: Revisiting an old disease

OBJECTIVE

We aimed to assess the frequency distribution of of ABO haemolytic disease of newborn (ABO-HDN) and to know the predictive value of immunohaematological tests in identifying at risk neonates.

BACKGROUND

ABO incompatibility, although a common cause of haemolytic disease of newborn, has several unaddressed issues related to it.

MATERIAL AND METHODS

A prospective study over 20 months was carried out in a tertiary care centre in South India. Blood grouping, Direct Antiglobulin test (DAT) and elution studies were performed on neonatal samples, whereas blood grouping, antibody screening and antibody titration were performed on maternal samples. In suspected cases, ABO-HDN was diagnosed after excluding other possible causes for haemolysis. The laboratory results were correlated with the clinical details to assess the predictive value of the tests.

RESULTS

Of the total 2856 pregnancies, 34% had ABO incompatibility. On testing with columnagglutination test (CAT), the overall DAT positivity and that among ABO-incompatible cases were 3.8% and 11.2%, respectively,) whereas by conventinal tube technique (CTT) it was 0.6% and 2.4% respectively. CAT was found to have higher sensitivity, and the predictive value was higher for CTT. Maternal IgG titre showed a positive linear relationship with the DAT strength and the rise in indirect bilirubin levels. The positive predictive value of combination of tests such as DAT, elution and titation was 94.12%, which was much higher than that of the individual tests.

CONCLUSION

DAT positivity is a predictor of early rise in serum bilirubin level, and a combination of tests has a better predictive value than individual tests towards development of clinically significant hyperbilirubinemia in ABO-HDN.

Deletion in the A4GALT Gene Associated with Rare "P null" Phenotype: The First Report from India

Background

The present report illustrates a case with rare "P null" phenotype due to a large deletion in chromosome 22q13.2 and with clinically significant anti-PP1P^k antibody. Patient blood management in such cases is challenging.

Case Report

The transfusion center supporting the tertiary care referral center in the southern part of India received a blood sample from a trauma case for pre-transfusion testing. An antibody to a high-frequency blood group antigen was initially suspected. Following extensive immune-hematological workup, the patient was diagnosed to have naturally occurring anti-PP1P^k antibody and a rare "P null" phenotype. The genomic DNA of the patient was analyzed by exome sequencing followed by Sanger's sequencing. Molecular diagnostics revealed a large 21-bp deletion in chromosome 22q13.2 which encodes the A4GALT gene, resulting in truncation of seven amino acids I245-251P and resulted in rare "P null" phenotype. Patient blood management strategies were adopted to manage the patient conservatively without blood transfusion.

Conclusion

A large deletion in chromosome 22q13.2 had resulted in a rare "P null" phenotype in the present case. The patient was a victim of a road traffic accident, required emergency hospitalization, as well as surgical intervention, and his plasma had antibodies to high-frequency antigens. A rare donor registry plays a major role in providing transfusion support to such cases.

Validation of Two Point of Care Devices for Hemoglobin Estimation in Blood Donors

Hemoglobin (Hb) estimation is a critical investigation in prospective blood donors. There are numerous techniques for Hb estimation, choosing an appropriate method is essential. Point of care devices (POC) have made quantification of Hb possible even in the field or community settings. Validation against a standard measure is necessary before implementing it for routine practice. With this background, we aimed to validate two new POC devices against a standard hematology analyzer for Hb estimation. An observational study on 100 donor venous blood samples was conducted. Hemoglobin was estimated using a Sysmex Hematology Analyzer (reference method) along with POC devices (CompoLab TM and True Hb Hemometer). Three statistical techniques were applied to validate Hb by the two POC devices. CompoLab TM measures 0.4 units more than the reference method and True Hb measures 0.4 units less than the reference method. Measures of Hb obtained from both the equipment showed moderate agreement with that of reference method (CompoLab TM ICC-0.74 and True Hb ICC-0.72). There were no systematic or proportional differences in the comparison of the two POC devices with the reference method. Within the limitations of this study, both the devices can be used for Hb estimation, as there was a substantial agreement of the measurements with the reference method. Other factors such as cost, turnaround time (TAT), ease of utilization should be considered to decide on the choice of equipment to be used.

Red blood cells under varying extracellular tonicity conditions: an optical tweezers combined with micro-Raman study

Extracellular tonicity has a significant influence on human red blood cell deformation capability. Advancements in the area of laser physics and optical trapping have opened up a plethora of applications for understanding cell structure and dynamics. Here, Raman Tweezers technique was employed to investigate the impact of extracellular tonicity by exposing human red blood cells to both hypertonic and hypotonic intravenous fluids. Heme aggregation was observed in hypertonic saline solution, accompanied with damage in membrane protein. Loss of intracellular hemoglobin in hypotonic solution was evident from the decrease in porphyrin breathing mode present at 752 cm^-1. Oxygen binding to the central iron in the red blood cell heme was also affected under both hyper/hypo tonicity conditions. Morphological deviation of discocytes to echinocytes/spherocytes were also evident from quantitative phase imaging. Principal component analysis have showed clear differentiation of samples in order to classify the control erythrocytes and the tonicity stressed erythrocytes. Present study has also demonstrated the application of Raman Tweezers spectroscopy as a potential tool for probing red blood cell under different stress conditions.

Human red blood cell behaviour in hydroxyethyl starch: probed by single cell spectroscopy

Hydroxyethyl starch (HES) is a commonly used intravenous fluid in hospital settings. The merits and demerits of its application is still a debatable topic. Investigating the interaction of external agents like intravenous fluids with blood cells is of great significance in clinical environments. Micro-Raman spectroscopy combined with an optical tweezers technique has been utilized for conducting systematic investigations of single live red blood cells (RBCs) under the influence of external stress agents. The present work deals with a detailed biophysical study on the response of human live red blood cells in hydroxyethyl starch using optical techniques. Morphological changes in red blood cells were monitored using quantitate phase imaging techniques. Micro-Raman studies suggest that there is a significant reduction in the oxy-haemoglobin level in red blood cells suspended in HES. The spectra recorded by using different probe laser powers has shown that the cells are more vulnerable in HES under the influence of externally induced stress than in blood plasma. In addition, the spectral results support the possibility of heme aggregation and membrane damage for red blood cells in HES under externally induced stress. Principle component analysis performed on the Raman spectra were able to effectively discriminate between red blood cells in HES and in blood plasma. The use of Raman tweezers can be highly beneficial in elucidating biochemical alterations happening in live, human red blood cell.

Hydroxyethyl starch (HES) is a commonly used intravenous fluid in hospital settings.