Positive Direct Antiglobulin Test: Is It a Risk Factor for Significant Hyperbilirubinemia in Neonates with ABO Incompatibility?

OBJECTIVE

 ABO blood group (ABO) incompatibility is a common cause of neonatal indirect hyperbilirubinemia. The direct antiglobulin test (DAT) can identify infants developing hemolytic disease. This study aims to evaluate the significance of DAT positivity among neonates with ABO incompatibility.

STUDY DESIGN

 This retrospective study included 820 neonates with blood group A or B who were born to blood group O mothers. The study group consisted of neonates (n = 79) who had positive DAT, and the control group consisted of infants (n = 741) who had negative DAT. Demographic and clinical data of the neonates regarding jaundice were collected and compared statistically.

RESULTS

 The bilirubin level at 24 hours of life (study group: 8 ± 2.6 mg/dL, control group: 6 ± 2.2 mg/dL, p < 0.001) and the highest bilirubin level (study group: 12.7 ± 3.6 mg/dL, control group: 10.4 ± 4.2 mg/dL, p < 0.001) were higher in infants with positive DAT. A total of 37 (46.8%) infants in the study group and 83 (11.2%) infants in the control group received phototherapy (PT) in the nursery (p < 0.001). In neonates with positive DAT, direct bilirubin level, duration of hospitalization, and PT in the nursery were higher (p = 0.002, <0.001, and <0.001, respectively), whereas hemoglobin level was lower (p < 0.001).

CONCLUSION

 In neonates with ABO incompatibility, a positive DAT is a risk factor for developing significant hyperbilirubinemia. Close follow-up of newborn infants with ABO incompatibility is crucial for early detection and treatment of neonatal jaundice to avoid early and late complications.

KEY POINTS

· The clinical spectrum of ABO incompatibility varies widely.. · The ABO incompatibility with positive DAT are at greater risk for high bilirubin levels.. · Infants with blood group incompatibilities must be monitored closely..

A study on diagnostic performance of different immunohematological diagnostic tests in assessing the prevalence of ABO Hemolytic Disease of Newborn in the antenatal O group mothers and their neonatal outcome in a tertiary care hospital in Northern India

BACKGROUND

Hemolytic disease of the newborn (HDN) results in the decreased lifespan of the red cells. HDN related to ABO incompatibility is mostly unnoticed because routine screening is not being done. This study was done to assess the prevalence of ABO-HDN and to compare different immunohematological tests. Methods-In this study 213 O group mothers and the 122 ABO-incompatible newborns born to them were included. Quantifying the maternal IgG anti-A/anti-B antibody titer was done by Conventional Tube Technique (CTT) using Dithiothreitol (DTT) pretreated maternal serum. Hemolysin test was performed on the mothers having titer > 256. These cases were followed up and, after delivery, were monitored for ABO HDN, along with direct antiglobulin testing and elution studies. The prevalence of ABO-HDN was calculated, and the different diagnostic parameters of the tests were calculated. Results- The prevalence of ABO-HDN in our population was estimated to be 1.7%, 6.1% & 10.6% in our population, O group mothers, and O group mothers with ABOincompatible newborns, respectively. Maternal titer≥ 512 strongly correlated with ABOHDN. DAT positivity is a good predictor of ABO-HDN, especially using sensitive techniques. Maternal IgG titers have the highest sensitivity & Negative Predictive Value, while DAT has the highest specificity & Positive Predictive Value. Conclusion - Maternal ABO antibody titration may be advocated in the centers to identify high-risk groups. It can advocate institutional delivery and dedicated follow-up of newborns with ABO-HDN. Blood grouping & DAT may be performed in all newborns born to O blood group to identify high-risk cases.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Does strengths of a positive direct antiglobulin test predicts the need for phototherapy and duration of phototherapy? - a single center, retrospective study

BACKGROUND

Use of Direct Antiglobulin test (DAT) in management of neonatal hyperbilirubinemia is conflicting.

OBJECTIVE

whether strength of positive DAT predicts the need for phototherapy, duration of phototherapy and need for major interventions.

METHODS

We retrospectively collected data on all DAT positive neonates with birth gestational age ≥32 weeks over six years (2014-2019). Data regarding blood group, DAT and clinical details were obtained from a hospital database. We also collected data on serial hemoglobin and other relevant laboratory parameters. We also collected data on infants receiving major interventions such as exchange transfusion, in-utero transfusion, immunoglobulins, and postnatal transfusion for the duration of the study period. All of these infants were electronically followed up for a period of 6 weeks. This study was approved by institutional audit authority. All the statistics were performed using SPSS software.

RESULTS

Out of 1285 DAT tests performed, only 91 infants were positive (7%), and 78 DAT positive infants were available for analysis. There were 54 infants with DAT (1+), 15 infants with DAT (2+), 7 infants with DAT (3+) and 2 infants with DAT (4+). There was no significant statistical difference in terms of need for phototherapy, duration of phototherapy, need for major interventions and hemoglobin levels at different time points between the groups (DAT 1+ Vs DAT ≥2+; DAT ≤2+ Vs DAT >2). A Total of 10 infants received major intervention, with one infant receiving all three interventions (DAT 3+ with significant maternal antibodies), 2 additional infants (both DAT1+) received exchange transfusion, 6 additional infants received immunoglobulin (2 infants: DAT 2+; 4 infants: DAT 1+) and one additional infant (DAT 1+) with significant maternal antibodies received a postnatal transfusion.

CONCLUSION

Strength of a DAT did not predict the need for phototherapy, duration of phototherapy, and the need for major hemolysis related intervention in the first 6 weeks of life.

[In macrohematuria, medication history also needs to be considered : Penicillin-induced immune hemolysis: a case report and review of literature]

BACKGROUND

Drug-mediated immune hemolysis is a rare but potentially life-threatening condition. Based on a case of penicillin-induced immune hemolysis, a structured literature review of case reports and studies on penicillin-mediated Drug-Induced Immune Hemolytic Anemia (DIIHA) was carried out.

CASE REPORT

A 28-year-old male patient presented to the emergency department with gross hematuria and non-specific abdominal complaints. The patient had a 10-day history of respiratory infection with bacterial tonsillitis, treated orally with penicillin V on an outpatient basis. Laboratory diagnostics detected pathologically altered direct and indirect hemolysis parameters. After stopping the medication, the patient's condition could be stabilized.

CONCLUSION

Diagnosis of penicillin-mediated immune hemolysis requires structured cooperation between clinic and laboratory, as clinical and serological findings may be highly variable with the risk of misdiagnosis. Due to the rarity of the disease, this case report is intended to raise awareness with respect to the triad of abrupt drop in hemoglobin levels in connection with drug therapy and in combination with a strongly positive direct Coombs test.

Comparison of solid-phase red cell adherence and microcolumn agglutination technology using untreated and enzyme-treated red blood cells

Screening for clinically significant antibodies is crucial in transfusion medicine and is a routine part of pre-transfusion testing. The indirect antiglobulin test (IAT) is the most reliable and effective test for detecting clinically significant alloantibodies reacting at the antihuman globulin phase. Two of the main methods used for antibody detection and identification are solid-phase red cell adherence (SPRCA) and microcolumn agglutination technology (CAT), with or without enzyme-treated red blood cells (RBCs). This study was undertaken to detect and identify alloantibodies by performing antibody screen (ABS) and antibody identification (ABID) testing using SPRCA and CAT, with and without ficin-treated RBCs. Residual patient samples collected between 1 December 2020 and 19 May 2021 were saved, de-identified, and frozen at ≤-30°C before testing for alloantibodies. Seventy antibodies were detected in 53 samples among the 203 samples that underwent an ABS. Of those samples, 150 (73.0%) were nonreactive, 47 (23.1%) yielded positive results with both CAT and SPRCA, and six (3.0%) yielded positive ABS results with SPRCA only. Fifty-three samples that underwent ABID by both methods yielded eight samples with antibodies identified by SPRCA only. Additional enhancement of the CAT method by the use of ficin-treated RBCs was required to detect seven of the eight SPRCA-only antibodies; one sample remained nonreactive regardless. SPRCA testing detected clinically significant antibodies without the addition of enzyme-treated RBCs that was necessary in the CAT testing.

Comparison of automated solid phase versus manual saline indirect antiglobulin test methodology for non-ABO antibody titration: Implications for perinatal antibody monitoring

BACKGROUND

Accurate antibody titration is crucial in prenatal evaluations to identify patients who need clinical monitoring for hemolytic disease of the fetus and newborn (HDFN) causing fetal anemia. This study compares the established gold standard method of manual tube saline indirect antiglobulin testing (SIAT) with the newer automated solid phase (ASP) method of antibody titration and aims to establish the critical titer threshold for ASP that corresponds to the previously established SIAT critical threshold of ≥16 used in our laboratory.

STUDY DESIGN AND METHODS

One hundred fifty-seven prenatal and donor plasma samples with known antibodies were tested using both SIAT and ASP methodologies and results were compared.

RESULTS

The study found that ASP titers were, on average, 1.33 dilutions higher than SIAT titers. The critical titer cutoff for ASP was determined to be ≥32, which is one tube higher than the SIAT cutoff of ≥16.

DISCUSSION

The ASP method for antibody titration offers greater reproducibility and efficiency compared with manual SIAT titration. This study suggests that a titer cutoff of ≥32 is appropriate for most clinically significant antibodies using ASP. However, further research is needed to determine the comparability of ASP with SIAT in samples with multiple antibodies, anti-M antibodies, and other less common antibodies. Validation of the ASP titer cutoff against HDFN clinical outcomes is required before implementing this test for routine use in perinatal antibody titration.

Favorable outcome without corticosteroids during post-artesunate delayed hemolysis with positive direct antiglobulin test in severe imported Plasmodium falciparum malaria, France

OBJECTIVES

Positive direct antiglobulin tests (DATs) have been reported in cases of post-artesunate delayed hemolysis (PADH), but the causal role of auto-immune hemolysis remains unclear. We aimed to analyze a cohort of patients with PADH and DAT during severe malaria.

METHODS

We describe PADH and DAT results in a 7-year multi-center retrospective cohort of patients receiving artesunate for severe imported malaria.

RESULTS

Of 337 patients treated with artesunate, 46 (13.6%) had at least one DAT result within 30 days of treatment initiation, and 25/46 (54.3%) had at least one positive DAT. Among 40 patients with available data, 17 (42.5%) experienced PADH. Patient characteristics were similar for patients with a positive or negative DAT, and DAT positivity was not associated with PADH occurrence (P = 0.36). Among patients, 5/13 (38.5%) with a positive DAT after day 7 experienced PADH, compared to 10/13 (76.9%) of those with a negative DAT after day 7 (P = 0.11). Overall, 41% of patients required blood transfusions, and outcome was favorable without corticosteroids, even in cases of PADH.

CONCLUSIONS

DAT does not appear to be a marker of PADH, but rather an indirect marker of an immune-mediated mechanism. DAT positivity should not lead to the administration of systemic corticosteroids during PADH.

Rates of phototherapy among ABO-incompatible newborns with a negative direct antiglobulin test

OBJECTIVE

We analyze phototherapy rates after implementation of a Hyperbilirubinemia Clinical Pathway (HCP), which placed full-term ABOi DAT negative newborns on the low risk phototherapy nomogram, rather than medium risk, as previously done.

STUDY DESIGN

A chart review was performed for ABOi newborns born ≥36 weeks gestation between January 2020 and October 2021. Primary outcome measures were rates of phototherapy across pre- and post-intervention groups and among DAT negative newborns.

RESULTS

There was an increased proportion of newborns assigned to the low risk curve after the intervention. There were no significant differences in phototherapy rates among the intervention groups, although there was a non-significant decrease in phototherapy rates among DAT negative newborns after the intervention. There were no increases in adverse outcomes.

CONCLUSIONS

Providers adhered to the guidelines after implementation of the HCP. ABOi DAT negative newborns can be viewed as low risk for hyperbilirubinemia requiring phototherapy.

Polyagglutinability phenomenon: a case report and review of the literature

BACKGROUND

Polyagglutinability of red blood cells is a rare immunological phenomenon, it is due to a cryptic antigen that is abnormally present on the surface of red blood cells. The aim of our work is to shed light on polyagglutinability, which is still poorly understood cause of discordance between the cell and serum tests and can sometimes have harmful transfusion consequences.

CASE PRESENTATION

We report the case of a 70-year-old African patient admitted for management of hemolytic anemia.

RESULTS

During the erythrocyte grouping, a discordance between the cell and serum tests was observed, with polyagglutinability for the RH phenotype, a positive AB control, and even a positive control. The direct antiglobulin test and the Coombs test were also positive. The same results were obtained even after washing the red blood cells and incubating them at 37 °C for 30 min. For transfusion purposes, erythrocyte genotyping was performed, and the patient was transfused with an A+ red blood cell unit with an RH Kell-compatible phenotype.

CONCLUSION

Polyagglutinability should always be taken into account when grouping anomalies are encountered. Although it may not show any symptoms, hemolysis is frequently observed during transfusions.

Hematologic Abnormalities After COVID-19 Infection: A Case of Coombs-Negative Hemolytic Anemia and Thrombocytopenia

The occurrence of hemolytic anemia in patients with active SARS-CoV-2 infection has been documented in medical literature. While relatively uncommon, there have been instances where this condition presents as a Coombs-negative hemolytic anemia. In this research study, we report a distinctive case of Coombs-negative hemolytic anemia and thrombocytopenia in a patient with a known history of COVID-19 infection. The patient demonstrated a favorable response to treatment involving the administration of steroids and intravenous immunoglobulin (IVIG) therapy. This case adds to the existing body of evidence regarding the hematological manifestations of SARS-CoV-2 infection, highlighting the importance of considering and managing hematological complications in patients with COVID-19.

Use of thiol reagents to disperse cold autoagglutination

Thiol reagents dithiothreitol (DTT) and 2-mercaptoethanol (2-ME) are sulfhydryl reagents that can be used to disperse cold autoagglutinins coating red blood cells (RBCs). DTT and 2-ME are primarily used when warm washing of the coated RBCs fails to successfully disperse the cold autoantibody. Using a weak concentration of DTT or 2-ME, the cold IgM agglutinin can be removed from the coated RBCs without disrupting the IgG or complement coating the RBCs. The treated RBCs can be used for ABO typing, antigen typing, or the direct antiglobulin test.

Convolutional neural network-based automatic classification for incomplete antibody reaction intensity in solid phase anti-human globulin test image

The precise classification of incomplete antibody reaction intensity (IARI) in hydrogel chromatography medium high density medium solid-phase Coombs test is essential for haemolytic disease screening. However, an automatic and contactless method is required for accurate classification of IARI. Here, we present a deep ensemble learning model that integrates five different convolutional neural networks into a single model for IARI classification. A dataset, including 1628 IARI images and corresponding labels of IARI categories ((-), (1 +), (2 +), (3 +), and (4 +)), was used. We trained our model using 1302 IARIs and validated its performance using 326 IARIs. The proposed model achieved 100%, 99.4%, 99.4%, 100%, and 100% accuracies in the ( −), (1 +), (2 +), (3 +), and (4 +) categories, respectively. The results were compared with those of manual classification by immunologists (average accuracy: 99.8% vs. 88.3%, p < 0.01). Following model assistance, all three immunologists achieved increased accuracy (average accuracy: + 6.1%), with the average accuracy of junior immunologists maximum increasing by 11.3%. The time required for model classification was 0.094 s·image^–1, whereas that required manually was 5.528 s·image^–1. The proposed model can thus substantially improve the accuracy and efficiency of IARI classification and facilitate the automation of haemolytic disease screening equipment.

DAT negative warm autoimmune haemolytic anaemia secondary to a mature cystic teratoma refractory to immunosuppressive therapy

Mature cystic teratomas (MCTs) have a rare but recognised association with IgG-mediated autoimmune haemolytic anaemia (AIHA). We present the first case of an MCT associated with IgA-mediated AIHA. We discuss the diagnostic challenges of patients presenting with a direct antiglobulin test negative AIHA picture and the importance of reviewing these cases with the local transfusion laboratory. We also review the treatment options for MCT associated AIHA. In particular, we note they are typically resistant to immunosuppression and that surgical resection should be considered at an early stage. Although MCTs are a rare cause of AIHA, they can be treated easily and should be excluded in young women presenting with AIHA, especially if resistant to corticosteroids.

Immune-mediated Coombs negative intravascular haemolysis in systemic lupus erythematosus (SLE)

A 27-year-old woman presented with a history of excessive hair loss, loss of appetite, loss of weight, amenorrhoea and loss of axillary and pubic hair for 6 months followed by fever and vomiting for 5 months and abdominal pain for 1 month. During the course of her illness, the patient developed intravascular haemolysis as evidenced by a drop in haemoglobin, indirect hyperbilirubinaemia, raised lactate dehydrogenase (LDH) and haemoglobinuria. Examination revealed severe pallor, mild icterus, elevated jugular venous pressure, generalised lymphadenopathy and hyperpigmentation. Investigations revealed severe anaemia, indirect hyperbilirubinaemia, raised LDH and negative Coombs test. Antinuclear antibody and anti-dsDNA, anti-Sm and anti-SS-A/Ro antibodies were positive and complement C3 was low. The patient was diagnosed to have systemic lupus erythematosus and immune-mediated intravascular haemolysis and was treated with prednisolone and hydroxychloroquine. Haemolysis resolved following steroid therapy, and during follow-up, there were no further episodes of haemolysis.

Late-onset myocardial infarction and autoimmune haemolytic anaemia in a COVID-19 patient without respiratory symptoms, concomitant with a paradoxical increase in inflammatory markers: a case report

BACKGROUND

In December 2019, a new coronavirus (named severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) spread from China, causing a pandemic in a very short time. The main clinical presentation of SARS-CoV-2 infection (COVID-19, coronavirus disease-2019) is pneumonia, but several cardiovascular complications may also occur (e.g., acute coronary syndromes, pulmonary embolism, stroke, arrhythmias, heart failure and cardiogenic shock). Direct or indirect mechanisms induced by SARS-CoV-2 could be implicated in the pathogenesis of these events.

CASE PRESENTATION

We report herein the third case of COVID-19 autoimmune haemolytic anaemia (AIHA) reported so far, which occurredwithout any other possible explanations in a Caucasian patient. The patient also suffered from ST-elevation myocardial injury.

CONCLUSIONS

Both complications occurred quite late after COVID-19 diagnosis and were probably precipitated by systemic inflammation, as indicated by a significant delayed increase in inflammatory markers, including interleukin-6 (IL-6).

[Autoimmune hemolytic anemia in emergency department]

Autoimmune hemolytic anemia is an uncommon disease that can be challenging to manage both for the emergency department physician and the general practitioner. The diagnosis is based on specific biological changes and on a positive direct Coombs test. Depending on the severity of the anemia and its clinical impact, an urgent blood transfusion can be required. However, ABO blood group typing and antibody screening may be impaired by autoantibodies. In case of vital need, a transfusion of ABO, Rh D and, if possible, C, c, E, e and Kell antigen matched red cells can be performed, before the complete achievement of the pre-transfusion testing. Further management includes the introduction of immunosuppression and the treatment of a possible underlying disease. Early contact with the hematologist, is strongly recommended.

Study for the Diagnostic Screening of Paroxysmal Nocturnal Hemoglobinuria in Older Patients with Unexplained Anemia and/or Cytopenia

BACKGROUND

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare acquired hematopoietic stem cell disease that may lead to weakness and death of patients, if unrecognized and untreated. Although consensus guidelines were reviewed recently for the diagnostic screening of PNH with multi-parameter flow cytometry (FCM), until now, no study has investigated the efficiency of such clinical indications in older patients.

METHODS

Overall, 20 centers participated in the study and a total of 1,689 patients were included, 313 of whom were at geriatric age and 1,376 were aged 18 - 64 years. We evaluated the efficiency of consensus clinical indications for PNH testing using FCM in peripheral blood samples and compared the results of older patients and patients aged 18 - 64 years.

RESULTS

PNH clones were detected positive in 7/313 (2.2%) of the older patients. Five (74.4%) of the patients with PNH clones had aplastic anemia, 1 had unexplained cytopenia, and 1 patient had myelodysplastic syndrome (MDS) with refractory anemia. PNH clones were not detected in any older patients who were screened for unexplained thrombosis, Coombs (-) hemolytic anemia, hemoglobinuria, and others (e.g., elevated lactate dehydrogenase (LDH), splenomegaly). We detected PNH clones in 55/1376 (4%) samples of the patients aged under 65 years. Forty-two (76.4%) patients with PNH clones had aplastic anemia, 2 patients had Coombs (-) hemolytic anemia, 3 patients had unexplained cytopenia, 1 patient had MDS with refractory anemia, 1 patient had hemoglobinuria, and 6 (10.9%) had others (e.g., elevated LDH, splenomegaly). PNH clones were not detected in any patients who were screened for unexplained thrombosis. There was no statistical difference between the geriatric population and patients aged 18 - 64 years in terms of clinical indications for PNH screening with FCM (p = 0.49).

CONCLUSIONS

Our results showed that the current clinical indications for PNH screening with FCM were also efficient in older patients. We suggest that older patients with unexplained anemia, myelodysplastic syndrome with refractory anemia, and unexplained cytopenia should be screened for PNH with FCM to identify patients who would benefit from treatment.

Saline-indirect antiglobulin test

A saline-indirect antiglobulin test (IAT) is performed without addition of enhancement media to increase the binding of antibody to the red blood cell antigen during the 37°C incubation. Although infrequently used as a primary means for antibody detection or identification, this test is useful because of the variety of possible applications in antibody identification studies. It is critical to the test sensitivity to allow enough incubation time (30-60 minutes) for maximum antibody binding to occur. The saline test can also be subject to a direct agglutination reading after immediate spin, room temperature, or incubation at 37°C before conversion to the IAT. This step allows further flexibility in assessing the reactivity of directly agglutinating allo- or autoantibodies in tests performed at 37°C or lower temperatures.

A Rare Non-Hemolytic Case of Idiopathic Cold Agglutinin Disease

BACKGROUND

Cold agglutinin disease is a very rare condition associated with agglutination of erythrocytes in cold environment usually due to IgM type antibodies. Other than hemolytic anemias, it may interfere with routine hemogram tests due to miscalculation of red blood cell count (RBC) and other hemogram parameters calculated with involvement of RBC. Awareness of the condition is important to overcome laboratory errors.

METHODS

We studied a peripheral blood smear and repeated the hemogram test at 37°C to establish the diagnosis of cold agglutinin disease.

RESULTS

Initial hemogram test results of the fifty-eight year-old man was as follows: RBC: 1.34 M/µL, hemoglobin (Hb): 12.4 g/dL, hematocrit (Htc): 11.8%, mean corpuscular hemoglobin (MCH): 92.4 pg, and mean corpuscular hemoglobin concentration (MCHC): 105 gr/dL. Despite the standard indirect Coombs test being negative, repeated tests at room temperature was 4+. We suspected cold agglutinin disease and repeated the hemogram test using the Bain-Marie method at 37°C and the test results showed RBC: 3.4 M/µL, hemoglobin: 12.6 g/dL, hematocrit: 30.2%, MCH: 31.7 pg, and MCHC: 41.8 g/dL.

CONCLUSIONS

Inappropriate hemogram results may be a sign of underlying cold agglutinin disease. Hemolytic anemia not always accompanies the disease; however, cold exposure may trigger erythrocyte agglutination in vitro and may cause erratic laboratory results.

Recurrent fetal hydrops with maternal M alloimmunisation: not a benign condition

Haemolytic disease of the fetus and newborn (HDFN) is associated with red cell antibodies. Anti-M usually results in a mild haemolysis and is rarely clinically significant. There is no established consensus on management of pregnancies with anti-M. A case of recurrent HDFN with maternal M alloimmunisation was identified at a tertiary hospital in Australia. We collected the patient and neonate's clinical and pathological data and interpreted the case with available literature. This is the first case in literature of recurrent fetal hydrops in the setting of M alloimmunisation. Neonate was delivered in a poor condition, intubated and admitted to the neonatal intensive care unit for ionotropic support, red cell transfusion and plasma transfusion for coagulopathy. Direct Coombs test was positive, confirming HDFN. Although anti-M rarely causes HDFN, accurate history, fetal surveillance and monitoring is essential for identification of fetal anaemia. Concurrent placental disease may increase fetal risk from anti-M antibodies.

Revisiting ABO incompatibility as a risk factor for significant neonatal hyperbilirubinemia

Babies with ABO incompatibility are often advised frequent biochemical screening and prolonged hospital stay. Our primary objective of the study was to compare serum bilirubin levels at 48 h and 96 h of age in neonates with and without ABO incompatibility. Our prospective study included neonates with gestation ≥ 34 weeks, with or without ABO incompatibility (92 in each group). A direct Coombs test was performed on cord blood. The mean serum bilirubin and haematocrit levels in both groups at 48 h and 96 h were comparable. The mean reticulocyte count of babies with ABO incompatibility was, however, significantly higher. Late preterm and term neonates with and without ABO incompatibility have similar bilirubin levels and no increased risk of significant hyperbilirubinemia. Prolonged hospitalisation of these neonates appears to be unnecessary.

Evans Syndrome with Acute Kidney Injury

Evans syndrome is a rare syndrome associated with the simultaneous or sequential development of autoimmune hemolytic anemia (AIHA) and idiopathic thrombocytopenic purpura (ITP). Furthermore, acute kidney injury (AKI) is a syndrome characterized by the rapid loss of kidney excretory function and is most often secondary to extrarenal events. However, AKI has rarely been recorded in Evans syndrome without systemic autoimmune disease and malignant tumors of the blood and lymphatic system. Herein, we report the case of a patient who exhibited Evans syndrome presenting with AKI. A 73-year-old woman presented with diarrhea, anuria, low platelet count, and developed a progressive increase of blood urea nitrogen and serum creatinine, as well as anemia with a positive direct Coombs test. We excluded hemolytic uremic syndrome, ITP, and leukemia. Treatment with antibiotics, rehydration therapy, and hemodialysis resulted in partial remission; thus, we diagnosed the patient with Evans syndrome presenting with AKI. The patient was successfully treated by the addition of steroid treatment. When AKI presents with hemolysis and thrombocytopenia, physicians should consider Evans syndrome, which can be appropriately treated when detected early.

Albumin-indirect antiglobulin test

Albumin was the first widely used additive solution for hemagglutination tests. Its major effect is to decrease the repulsive forces that keep red blood cells (RBCs) apart. This effect may enable some RBC antibodies, particularly those in the Rh blood group system, to directly agglutinate antigen-positive RBCs after 37°C incubation. The impact of albumin on antibody binding before detection by an indirect antiglobulin test (IAT) is minimal. Use of albumin in antibody identification may help with separation of RBC antibody specificities in a mixture when one or more antibodies demonstrate reactivity after 37°C incubation. Warm autoantibodies can show decreased reactivity in albumin IATs, allowing recognition of underlying alloantibodies.

Red Blood Cell Alloimmunization in Multitransfused Pediatric Population in a Tertiary Care Hospital

OBJECTIVES

To estimate the prevalence and specificity pattern of red blood cell (RBC) alloimmunization among pediatric multitransfused patients, and to identify the factors associated with alloimmunization.

METHODS

This was a descriptive cross-sectional study conducted among mutitransfused pediatric patients over a period of two years. The relevant clinical details of patients were collected, and RBC antibody screening was done. Samples with positive antibody screen were subjected to antibody identification. Patient factors were analysed to find any significant relation to the development of RBC alloimmunization.

RESULTS

Alloantibodies were obtained in 4 (6.35%) of the total 63 patients, and autoantibody in 1 (1.59%). The specificities of alloantibodies identified were all against Rh antigens-one each of anti E, anti c, anti Cw and anti D + anti C. A significant association was seen between development of alloimmunization and first transfusion at more than 2 y of age.

CONCLUSIONS

RBC alloimmunization against Rhesus (Rh) antigens is a significant problem for multitransfused children in our population. Extended RBC phenotyping at least for antigens of the Rh system and provision of antigen matched RBCs may be an option for such children, where ongoing transfusion requirement is anticipated.

Assessment of common red blood cell pretreatments to yield an accurate serologic antigen phenotype compared with genotype-predicted phenotype

For patients requiring multiple transfusions and patients with positive direct antiglobulin tests (DATs), an extended red blood cell (RBC) phenotype can provide valuable information and help to determine the risk of forming alloantibodies. In some instances, the phenotype may be used for prophylactic matching. Phenotyping in this patient population is often hindered by the presence of circulating donor cells and/or by a positive DAT. Several methods, such as EDTA glycine acid (EGA) treatment to remove IgG, hypotonic saline wash to separate autologous RBCs, or reticulocyte separation, are often used in these situations to isolate patient RBCs for serologic phenotyping. This study aimed to determine the accuracy of each RBC pretreatment method by comparing serologically determined antigen types with those predicted by RBC genotyping. Forty-eight peripheral blood samples from recently transfused patients were phenotyped for selected antigens in the Rh, Kell, MNS, Duffy, and Kidd systems. Treatment methods for the sample sets were reticulocyte separation (N = 12), EGA (N = 16), and hypotonic saline wash (N = 20). DNA was extracted using standard methods, and genotyping was performed using the HEA BeadChip panel. In addition, 21 samples positive for RBC-bound IgG were EGA-treated up to two times. These samples were analyzed pre- and post-EGA treatment for RBC-bound IgG by tube DAT and by flow cytometry with fluorescein isothiocyanate-labeled anti-human IgG. After reticulocyte separation, 3 of the 12 samples had discordant types with one antigen each: Fy^b, N, and K; serologic results were negative compared with genotype-predicted positive phenotype results. The EGA-treated sample set showed one discordant type: Fy^b; serologic results were negative compared with genotype-predicted positive phenotype results. Four of the 20 samples had discordant types involving the following antigens: Fy^b, N, e, and M; serologic results were negative compared with genotype-predicted positive phenotype results. After EGA treatment of 21 samples, 14 (67%) were negative for RBC-bound IgG by tube DAT, and 7 remained positive. Using flow cytometry, EGA treatment rendered only 4 samples negative, and 17 remained positive. In the antigen testing sample set of 48 samples, 10 of 511 total antigen types tested were discordant. Discordant types were most frequent in the hypotonic saline wash sample set (N = 6). In the flow cytometry sample set, 48 percent of the samples negative by tube DAT after EGA elution had detectable RBC-bound IgG by flow cytometry. These findings suggest that caution should be taken when using phenotype results from all pretreated RBCs and support the use of RBC genotyping to predict RBC antigen expression in samples from recently transfused patients.

For patients requiring multiple transfusions and patients with positive direct antiglobulin tests (DATs), an extended red blood cell (RBC) phenotype can provide valuable information and help to determine the risk of forming alloantibodies. In some instances, the phenotype may be used for prophylactic matching. Phenotyping in this patient population is often hindered by the presence of circulating donor cells and/or by a positive DAT. Several methods, such as EDTA glycine acid (EGA) treatment to remove IgG, hypotonic saline wash to separate autologous RBCs, or reticulocyte separation, are often used in these situations to isolate patient RBCs for serologic phenotyping. This study aimed to determine the accuracy of each RBC pretreatment method by comparing serologically determined antigen types with those predicted by RBC genotyping. Forty-eight peripheral blood samples from recently transfused patients were phenotyped for selected antigens in the Rh, Kell, MNS, Duffy, and Kidd systems. Treatment methods for the sample sets were reticulocyte separation (N = 12), EGA (N = 16), and hypotonic saline wash (N = 20). DNA was extracted using standard methods, and genotyping was performed using the HEA BeadChip panel. In addition, 21 samples positive for RBC-bound IgG were EGA-treated up to two times. These samples were analyzed pre- and post-EGA treatment for RBC-bound IgG by tube DAT and by flow cytometry with fluorescein isothiocyanate–labeled anti-human IgG. After reticulocyte separation, 3 of the 12 samples had discordant types with one antigen each: Fy^b, N, and K; serologic results were negative compared with genotype-predicted positive phenotype results. The EGA-treated sample set showed one discordant type: Fy^b; serologic results were negative compared with genotype-predicted positive phenotype results. Four of the 20 samples had discordant types involving the following antigens: Fy^b, N, e, and M; serologic results were negative compared with genotype-predicted positive phenotype results. After EGA treatment of 21 samples, 14 (67%) were negative for RBC-bound IgG by tube DAT, and 7 remained positive. Using flow cytometry, EGA treatment rendered only 4 samples negative, and 17 remained positive. In the antigen testing sample set of 48 samples, 10 of 511 total antigen types tested were discordant. Discordant types were most frequent in the hypotonic saline wash sample set (N = 6). In the flow cytometry sample set, 48 percent of the samples negative by tube DAT after EGA elution had detectable RBC-bound IgG by flow cytometry. These findings suggest that caution should be taken when using phenotype results from all pretreated RBCs and support the use of RBC genotyping to predict RBC antigen expression in samples from recently transfused patients.

Serologic problems associated with administration of intravenous immune globulin (IVIg)

Intravenous immune globulin (IVIg) is manufactured from large pools of donor plasma and contains a high diversity of antibodies, primarily IgG. For this reason, IVIg is routinely used as antibody replacement therapy for patients having primary immunodeficiencies. In 1981, IVIg was also found to be a strong immunomodulator of various inflammatory and autoimmune conditions. This observation has led to the exponential increase in the use of IVIg throughout the world, with the United States and Canada being the biggest users of IVIg. Although relatively rare, adverse events, such as hemolytic anemia and thrombosis, can complicate the administration of IVIg. More frequently, the administration of IVIg can cause serologic challenges for the transfusion service including ABO discrepancies, positive direct antiglobulin tests, positive antibody detection tests, and incompatible crossmatches. This article will review each of the potential transfusion service challenges associated with IVIg administration.

Pembrolizumab-induced Autoimmune Hemolytic Anemia and Hemophagocytic Lymphohistiocytosis in Non-small Cell Lung Cancer

We herein report a 78-year old man with squamous cell carcinoma of the lungs treated with pembrolizumab. At 10 days after the administration of pembrolizumab, he showed progressive anemia and increased levels of bilirubin. Because the findings of a direct coombs test and cold hemagglutinin were positive, we diagnosed the patient with autoimmune hemolytic anemia and treated him with prednisolone. Subsequently, he was admitted to our hospital owing to fatigue, a high fever, and jaundice. His clinical findings met the diagnostic criteria of hemophagocytic lymphohistiocytosis, and he was rescued with a high dose of glucocorticoids. Marked tumor regression was obtained and has been maintained since then.

Use of the prewarm method for detecting clinically significant alloantibodies in the presence of cold autoantibodies

The prewarm (PW) method is useful for detecting and identifying clinically significant antibodies that bind to red blood cells and complement at 37°C and for avoiding antibodies that bind at temperatures less than 37°C. Antibodies that bind at temperatures less than 37°C are often cold autoantibodies that may be present in the serum of healthy individuals and are usually not clinically significant. The PW method is useful when these cold autoantibodies have a wide thermal range and interfere with standard testing methods by reacting at the 37°C and antihuman globulin test phases. When using the PW method, it is important to identify underlying, potentially clinically significant alloantibodies during pretransfusion testing to ensure the most appropriate component will be selected for transfusion.

Comparison of heel stick sample with placental blood sample for pretransfusion testing

BACKGROUND

Published studies demonstrate that placental blood samples provide acceptable results for various laboratory tests, but these studies did not include pretransfusion testing. The aim of this study was to show concordance between heel stick and placental blood sample pairs for pretransfusion testing and to validate tube and gel method for placental samples. Using placental blood samples for pretransfusion testing potentially reduces the amount of blood collected from newborns for initial laboratory tests.

STUDY DESIGN AND METHODS

Placental samples were collected for pretransfusion tests at birth from 32 newborns with less than 2000 g birthweight and less than 35 weeks to compare the results with the heel stick samples from the same newborns. ABO and D typing, direct antiglobulin test (DAT) with IgG, and antibody screen tests were performed on these sample pairs. For ABO and D typing both tube and gel methods were used to validate both methods for the placental samples.

RESULTS

This study shows 100% concordance in 32 sample pairs for ABO, D, and DAT tests. Antibody screen results were compared on 29 sample pairs. All 28 sample pairs were concordant, but one placental blood sample was more sensitive to detect a weak maternal antibody than its corresponding heel stick sample was.

CONCLUSION

The results of this study validated that placental blood samples can be used in place of heel stick samples and are suitable for pretransfusion testing. This study also validated ABO and D typing by tube and gel methods for placental samples.

Clinically significant naturally occurring anti-N and anti-S in a blood donor: a rare finding

To the Editors: Alloimmunization is triggered when an individual whose red blood cells (RBCs) are lacking particular antigens is exposed to these antigens through transfusion or pregnancy, causing the formation of immune antibodies. In addition to these exogenous exposures, underlying inflammatory or autoimmune conditions may lead to formation of unexpected antibodies. Individual factors also play a role, since some people are responders and others are non-responders. We report a case of naturally occurring alloanti-N and alloanti-S in a healthy D+ blood donor. Both antibodies were reactive over a wide thermal amplitude and hence were potentially clinically significant. This case highlights the importance of incorporating the indirect antiglobulin test (IAT) to test for unexpected RBC antibodies for all blood units as a routine protocol.

Low-ionic-strength saline solution-antiglobulin test (LISS-AGT)

The use of low-ionic-strength saline (LISS) solution as an enhancement for antibody screening and crossmatching was first described by Löw and Messeter in 1974. This method allowed for a reduced incubation time while maintaining adequate specificity and sensitivity of the antiglobulin test (AGT). Since then, the LISS-AGT tube method has been widely used in antibody detection and identification, as well as compatibility testing. As initially described, the method used red blood cells suspended in LISS. Modifications of the method led to development of the commercially prepared LISS additive solutions in use today. The LISS-AGT can be used effectively to detect alloantibodies of all major blood groups in antibody detection, antibody identification, and crossmatching procedures.

[A Slightly Different Gastroenteritis]

A Slightly Different Gastroenteritis Abstract. We report the case of a 81-year-old female presenting with gastroenteritic symptoms and laboratory findings of a hemolytic anemia, thrombocytopenia and acute renal failure with fatal outcome. A hemolytic-uremic syndrome caused by an infection with EHEC was diagnosed. As a further complication, a urinary tract infection with K. pneumoniae was diagnosed and treated.

Severe post-artesunate delayed onset anaemia responding to corticotherapy: a case report

Delayed onset haemolysis occurring post-artesunate and post-artemisinin combination therapy is secondary to delayed clearance of infected erythrocytes spared by pitting during treatment. We report a case of severe post-treatment delayed haemolytic anaemia with a positive direct antiglobulin test and a positive response to corticosteroid therapy, suggesting an associated immune mechanism.

[Blood Transfusion Selection in Patients with Autoimmune Hemolytic Anemia Producing Class Antibodies]

OBJECTIVE

To analyze the reasons for the incompatibility of cross matching in lymphoma patients complicated by autoimmune hemolytic anemia (AIHA), and to provide compatible blood to patients for multiple blood transfusion.

METHODS

The test tube method was used for routine identification of ABO blood group, Rh typing and direct anti-globulin test; the patients antibody was identified by saline water method, micro column gel card; and the saline water method, Polybrene method and antiglobulin method were used for blood cross matching test of the patients.

RESULTS

In the serum of the patient, positive autoantibodies were detected, in the elution, the Ce antibody was detected. After infusion of the corresponding antigen-negative blood, the patient's hemoglobin level was significantly improved.

CONCLUSION

Only firstly accurately identifying antibodies existed in serum and elution, then selecting corresponding antigen negative blood, can ensure the safety and effectiveness of blood transfusion.

The Direct Antiglobulin Test: Indications, Interpretation, and Pitfalls

The direct antiglobulin test (DAT; sometimes referred to as the "Coombs" test) continues to be one of the most widely used assays in laboratory medicine. First described about 70 years ago, it is elegantly simple in design, yet it is widely complex in its applications and interpretations, and it is prone to false-positive and false-negative results. The overall objective of our review is to provide practicing pathologists with a guide to identify situations when the DAT is useful and to highlight disease-specific shortcomings as well as general pitfalls of the test. To accomplish these goals, this review will discuss the following: (1) the history of the DAT, (2) how the test is performed in the clinical laboratory, (3) clinical situations for its use, (4) its interpretation, and (5) the pitfalls associated with DAT assays, including causes of false positivity.

Autoanti-C in a patient with primary sclerosing cholangitis and autoimmune hemolytic anemia: a rare presentation

Primary sclerosing cholangitis (PSC) is rarely associated with autoimmune hemolytic anemia (AIHA), and the presence of specific autoantibodies has not been reported previously. We present a unique case report of PSC associated with AIHA implicating autoanti-C. A 17-year-old girl was admitted to our hospital with PSC along with AIHA. Her blood sample demonstrated a positive direct antiglobulin test and a positive autocontrol in the antihuman globulin phase, confirming the patient had warm-reactive AIHA. Further testing showed the possibility of anti-C. The patient’s Rh phenotype was C+D+E–c–e+. Further testing with select cells, serial alloadsorption, and an elution confirmed anti-C specificity. The patient was transfused with two C–, crossmatch-compatible packed red blood cell units. The patient’s hemoglobin level and general condition showed improvement. This unique case report shows PSC associated with AIHA caused by autoanti-C. Usually, warm AIHA presents with a panreactive pattern, and it is difficult to find compatible blood. In this rare case, we could determine the specific antibody; efforts should always be made in cases of AIHA to identify the specificity of autoantibody.

The Augustine blood group system, 48 years in the making

The high-prevalence antigen, Ata, was first identified in 1967, but it was not until 2015 that Ata became AUG1 of a new blood group system, Augustine (AUG). The new system was established after the identification of the gene encoding Ata and the recognition of a null phenotype (AUG:–1,–2) in an At(a–) patient with an antibody (anti-AUG2) reactive with At(a–) red blood cells. The At(a–) phenotype is very rare and, with the exception of the one family with the null phenotype, has only been found in individuals of African origin. Anti-Ata has been implicated in immediate and delayed hemolytic transfusion reactions, but not in severe hemolytic disease of the fetus and newborn. The Augustine gene is SLC29A1, which encodes the equilibrative nucleoside transporter ENT1. At(a–) (AUG:–1,2) results from homozygosity for c.1171G>A, encoding Glu391Lys, whereas the AUGnull (AUG:–1,–2) phenotype results from homozygosity for a splice site mutation, c.589+1G>C, in the only family where it has been found. Absence of ENT1 in that family may be associated with pseudogout and abnormal bone calcification.

Progressive Disseminated Histoplasmosis with Coomb's Positive Hemolytic Anemia in an Immunocompetent Host

Progressive Disseminated Histoplasmosis (PDH) is mainly described in immuno-compromised individuals and rare in immuno-competent subjects. Here we report a case of progressive disseminated histoplasmosis with Comb's positive hemolytic anemia, which is infrequently reported from a country like India where histoplasmosis is not an endemic mycosis.

[Quantities and function of NK cells in patients with positive BMMNC-Coombs test and cytopenia]

OBJECTIVE

To test NK cell quantities and function in patients with positive BMMNC-Coombs test (CBCPC) and cytopenia and to explore how NK cell participate in the progress of this disease.

METHODS

The percentage of CD3(-)CD56(+) NK cell in peripheral blood lymphocytes, the expression of activating receptor (NKG2D, NKp46, NKp44), inhibitory receptor (CD158a, CD158b), perforin and granzyme-β were detected by flow cytometry. All samples were taken from 42 patients (22 newly diagnosed and 20 in remission) and 12 healthy volunteers. The correlation between the above parameters and patients' clinical profile were evaluated.

RESULTS

①The percentage of CD3(-)CD56(+) NK cell in new diagnosed and remission CBCPC patients were significantly lower than that in healthy control [(10.04 ± 5.33)% vs (19.94 ± 7.38)%; (11.62 ± 6.80)% vs (19.94 ± 7.38)%, all P<0.01]. ② The expression of activating receptor NKG2D in new diagnosed CBCPC patients was significantly higher than that in remission group and healthy control [(74.03±18.24)% vs (45.97±29.45)%; (74.03±18.24)% vs (41.89± 15.34)% , P <0.01]. ③The expression of inhibitory receptor CD158a in new diagnosed CBCPC patients was significantly lower than that in remission group and healthy control (median: 3.72% vs 16.10%, P= 0.015; 3.72% vs 11.04%, P=0.025). ④The expression of perforin in new diagnosed and remitted CBCPC patients were significantly higher than that in healthy controls [(75.71±10.14) % vs (57.20±18.85)%, P= 0.018; (77.88±22.82)% vs (57.20±18.85)%, P=0.008]. ⑤The product of NK cell percentage and perforin expression in new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.68±4.54)% vs (12.13±5.19)%, P=0.011; (8.24±5.80)% vs (12.13±5.19)%, P=0.023]. The product of NK cell percentage and granzyme-β expression in the new diagnosed and remission CBCPC patient were significantly lower than that in healthy control [(7.83±5.26)% vs (14.79±8.37)%, P=0.008; (8.37 ± 6.83)% vs (14.79±8.37)%, P=0.012].

CONCLUSION

Deceased quantities and impaired total NK function might play a role in pathogenesis of CBCPC.