Erythrocyte autoantibodies, autoimmune haemolysis and pregnancy

Immunohematological testing and transfusion management of the prenatal patient

The primary indication for immunohematological testing in the prenatal patient is to detect and identify maternal red cell antibodies. If there are antibodies that are expected to hemolyze the fetus' red cells, their strength of reactivity must be tested, and the fetus' antigen status determined. After delivery, testing is performed to assess the extent of fetomaternal hemorrhage, as a large hemorrhage may require other therapeutic interventions. Another major role for immunohematological testing is to select blood components appropriately when intrauterine transfusion is required for fetal anemia resulting from maternal alloimmunization or some other cause. Supplementation with molecular methods has transformed the practice of immunohematology, particularly as it applies to typing for the D antigen of the Rh blood group system. Notwithstanding the advances in testing, close coordination and communication between the transfusion service and the obstetrics service are the foundation for ensuring the finest care for prenatal patients, and for new mothers and their infants. This review describes testing and transfusion practices for prenatal patients, using case presentations to highlight the management of selected immunohematological findings. It also includes a discussion of key patient management topics that are currently unresolved.

Autoimmune Hemolytic Anaemias in Pregnancy: Experience in a Tertiary Care Hospital in South India

Background

Autoimmune hemolytic anaemia is very rare and there is limited data regarding their pregnancy outcomes. Hence we aimed to study the maternal and perinatal outcomes in pregnancies with autoimmune hemolytic anaemias (AIHA).

Methods

A retrospective descriptive study of pregnant women with AIHA, who delivered at SJMCH between January 2011 and January 2016 was carried out. Their antenatal and labour records were reviewed and demographic details noted.The primary outcome measures studied were-the prevalence of AIHA, gestational age at delivery, antepartum, intrapartum and postpartum complications, mode of delivery and requirement of transfusion of blood and blood products. The secondary outcome measures studied included neonatal outcomes such as low birth weight, intrauterine growth restriction and need for intensive care. The data is presented as descriptive statistics, including means and percentage.

Results

The prevalence of AIHA was (18/12,420) 0.14%. The mean gestational age at delivery was 34 weeks; 100%, 77% and 50% had antenatal, intra partum or postpartum complications, respectively. 44% had preeclampsia, 38% intrauterine growth restriction and 16% preterm labour. 83% required additional drugs for treatment of AIHA.72% had vaginal delivery; 28% had caesarean delivery; 33% were transfused antenatally and 22% postnatally; 50% of the babies were preterm and required intensive care, 66% had low birth weight. There was no maternal mortality.

Conclusion

Multidisciplinary approach, early diagnosis and detection of autoimmune hemolytic anaemia and complications, good antenatal care, judicious transfusions and delivery at tertiary care centre are the keys to successful outcomes.

Implementation of a Standardized Prenatal Testing Protocol in an Integrated, Multihospital Health System

OBJECTIVES

When our institution grew into an integrated multihospital health system, we were faced with the need to standardize laboratory processes, including blood bank processes, across all locations. The purpose of this article is to describe our experience of standardizing the protocols for prenatal testing.

METHODS

For each hospital in the system, we established service tiers to define tests offered on site or referred to another location. For each prenatal test, we examined the related processes for ways to improve uniformity, efficiency, and reliability. Throughout this process of standardization, we collaborated with the clinical services to gain concurrence on the interpretation and reporting of results.

RESULTS

We created and implemented a uniform protocol for testing prenatal patients. The protocol standardized the definition of critical titer, instituted criteria to identify passively acquired anti-D, and established a process for the follow-up of women with inconsistent serologic results on Rh(D) typing.

CONCLUSIONS

Close collaboration with the clinical services ensured that our testing protocol is aligned with the needs of the integrated obstetrics service in the health system. The approach described in this article may provide a plan outline for pathologists facing similar challenges at other integrated health systems.

Difficult Cases of Autoimmune Hemolytic Anemia: A Challenge for the Internal Medicine Specialist

Autoimmune hemolytic anemia (AIHA) is diagnosed in the presence of anemia, hemolysis, and direct antiglobulin test (DAT) positivity with monospecific antisera. Many confounders of anemia and hemolytic markers should be included in the initial workup (i.e., nutrients deficiencies, chronic liver or kidney diseases, infections, and cancers). Besides classical presentation, there are difficult cases that may challenge the treating physician. These include DAT negative AIHA, diagnosed after the exclusion of other causes of hemolysis, and supported by the response to steroids, and secondary cases (infections, drugs, lymphoproliferative disorders, immunodeficiencies, etc.) that should be suspected and investigated through careful anamnesis physical examination, and specific tests in selected cases. The latter include autoantibody screening in patients with signs/symptoms of systemic autoimmune diseases, immunoglobulins (Ig) levels in case of frequent infections or suspected immunodeficiency, and ultrasound/ computed tomography (CT) studies and bone marrow evaluation to exclude hematologic diseases. AIHA occurring in pregnancy is a specific situation, usually manageable with steroids and intravenous (iv) Ig, although refractory cases have been described. Finally, AIHA may complicate specific clinical settings, including intensive care unit (ICU) admission, reticulocytopenia, treatment with novel anti-cancer drugs, and transplant. These cases are often severe, more frequently DAT negative, and require multiple treatments in a short time.

Coombs-negative haemolytic anaemia in pregnancy: A case report

We present a rare case of Coombs-negative autoimmune haemolytic anaemia in a multiparous woman in secondary care. There were no known underlying medical or obstetric risk factors for haemolytic anaemia. Following extensive investigation and a therapeutic trial of oral corticosteroids, a diagnosis was made. Autoimmune haemolytic anaemia is potentially fatal, and prompt diagnosis with haematology input is essential to ensure maternal and fetal safety in pregnancy and the puerperium. With only a small number of cases of Coombs-negative autoimmune haemolytic anaemia reported in the literature, we present this rare case for discussion. We highlight the importance of thorough investigation of refractory anaemia in pregnancy and consider the associated challenges.

•

Anaemia is pregnancy is common.

•

Refractory anaemia should be thoroughly investigated, it can be associated with increased maternal morbidity and mortality.

•

Coombs negative anaemia in pregnancy is rare

•

We report a case report of Coombs negative anaemia in pregnancy, with no significant underlying medical or family history.

Benefits and Risks of IgG Transplacental Transfer

Maternal passage of immunoglobulin G (IgG) is an important passive mechanism for protecting the infant while the neonatal immune system is still immature and ineffective. IgG is the only antibody class capable of crossing the histological layers of the placenta by attaching to the neonatal Fc receptor expressed at the level of syncytiotrophoblasts, and it offers protection against neonatal infectious pathogens. In pregnant women with autoimmune or alloimmune disorders, or in those requiring certain types of biological therapy, transplacental passage of abnormal antibodies may cause fetal or neonatal harm. In this review, we will discuss the physiological mechanisms and benefits of transplacental transfer of maternal antibodies as well as pathological maternal situations where this system is hijacked, potentially leading to adverse neonatal outcomes.

Pregnancy-associated immune-mediated hemolytic anemia in a dog

OBJECTIVE

To describe the clinical presentation, diagnostic investigations, and outcome of a dog with pregnancy-associated immune-mediated hemolytic anemia.

CASE SUMMARY

A 6-year-old, pregnant Bichon Frise was presented due to lethargy, inappetence, and progressive regenerative anemia with spherocytosis. The dog had been recently receiving ranitidine and amoxicillin/clavulanate. An in-house saline agglutination test identified marked agglutination and a urinalysis identified hemoglobinuria. Thoracic and abdominal imaging, as well as infectious diseases testing, was unremarkable. The bitch started whelping shortly following hospitalization, and the anemia progressively resolved without any other intervention. Ranitidine and amoxicillin/clavulanate were re-introduced within the following 2 months but the anemia did not reoccur. In light of these findings, a diagnosis of pregnancy-associated immune-mediated hemolytic anemia was made.

NEW OR UNIQUE INFORMATION PROVIDED

Pregnancy-associated immune-mediated hemolytic anemia should be considered in female dogs that develop severe hemolytic anemia during pregnancy and may resolve spontaneously following parturition.

Diagnosis and treatment of autoimmune hemolytic anemia in adults: Recommendations from the First International Consensus Meeting

Autoimmune hemolytic anemias (AIHAs) are rare and heterogeneous disorders characterized by the destruction of red blood cells through warm or cold antibodies. There is currently no licensed treatment for AIHA. Due to the paucity of clinical trials, recommendations on diagnosis and therapy have often been based on expert opinions and some national guidelines. Here we report the recommendations of the First International Consensus Group, who met with the aim to review currently available data and to provide standardized diagnostic criteria and therapeutic approaches as well as an overview of novel therapies. Exact diagnostic workup is important because symptoms, course of disease, and therapeutic management relate to the type of antibody involved. Monospecific direct antiglobulin test is considered mandatory in the diagnostic workup, and any causes of secondary AIHA have to be diagnosed. Corticosteroids remain first-line therapy for warm-AIHA, while the addition of rituximab should be considered early in severe cases and if no prompt response to steroids is achieved. Rituximab with or without bendamustine should be used in the first line for patients with cold agglutinin disease requiring therapy. We identified a need to establish an international AIHA network. Future recommendations should be based on prospective clinical trials whenever possible.

Presumed immune-mediated haemolytic anaemia associated with pregnancy in a cat

Case summary

A 7-year-old female entire Birman presented with acute-onset haemorrhagic vulvar discharge. Moderate, normocytic, normochromic, non-/pre-regenerative anaemia, along with a moderate mature neutrophilia, were seen on haematology. Saline test for agglutination was positive. No haemotropic mycoplasmas were identified. Serum biochemistry revealed severe hyperbilirubinaemia. Retroviral testing was negative. Serology for toxoplasmosis revealed a titre of 1:512. Abdominal ultrasound identified a large uterus, containing at least three advanced-stage fetuses, two of which failed to exhibit independent motion or cardiac activity. Ovariohysterectomy was performed. Histology demonstrated mild, multifocal suppurative placentitis, with Gram staining revealing no evidence of bacteria. Complete resolution of the anaemia was seen within 1.5 months of ovariohysterectomy.

Relevance and novel information

Immune-mediated haemolytic anaemia (IMHA) in association with pregnancy has not been previously reported in cats. This case represents a potential novel cause for IMHA in cats, which resolved following ovariohysterectomy.

Autoimmune hemolytic anemia and ovarian dermoid cysts in pregnancy

Ovarian teratoma is a rare cause of autoimmune hemolytic anemia (AIHA) by warm antibodies, resistant to corticosteroid therapy. This also implies that ovarian teratoma should be included in the differential diagnosis of AIHA, whether or not associated with pregnancy. We present a case of a primigravida who presented with ovarian dermoid cysts and AIHA at 24 weeks of gestation. The patient received corticosteroids, intravenous immunoglobulin, rituximab, and multiple blood transfusions, with no significant improvement. Hemoglobin levels returned to normal only after laparoscopic ovarian cystectomy. Autoimmune hemolytic anemia caused by dermoid cyst is a rare condition especially in pregnancy. However, in light of similar case reports and review of the existing literature, we conclude that surgical excision should be considered when AIHA and ovarian teratoma coexist.

Immunohematological and clinical characterizations of mixed autoimmune hemolytic anemia

BACKGROUND AND AIM:

Patients with warm autoimmune hemolytic anemia (AIHA) may carry immunoglobulin (Ig) M antibodies that react at room temperature and are nonpathological, but few may have cold agglutinins that react at or above 30°C and are referred to as “mixed” AIHA (MAIHA). Here, we present our experience on characterizing MAIHA both clinically and serologically.

MATERIALS AND METHODS:

Out of 134 AIHA patients, 13 diagnosed as MAIHA were subjected to detailed immunohematological characterization. Most patients were severely anemic and required urgent transfusions. Resolution of blood group discrepancy, elution, Donath-Landsteiner test, and adsorption study were performed following established protocol. “Best match” blood units were selected and transfused to patients.

RESULTS:

Eight of the 13 patients had severe hemolysis. The median age of patient was 37 years with a female preponderance and secondary MAIHA was observed in 8 (61.5%) patients. Blood group discrepancy was encountered in 4 (30.8%) patients. Multiple red cell bound autoantibodies and high titer serum-free IgM autoantibodies were detected in all samples. Twenty-nine units of “best match” packed red blood cells were transfused to 12 patients without any adverse reaction. Improvement in hematological and biochemical values was observed in all follow-up patients.

CONCLUSION:

Patients with MAIHA often present with severe hemolysis necessitating blood transfusions. While red cells are coated with multiple autoantibodies, both warm reactive IgG and cold reactive IgM autoantibodies are present in the serum. These serological complexities not only render a crossmatch incompatibility but often lead to blood group discrepancy. “Best match” blood transfusion is always lifesaving.

Anemia in Pregnancy: A Pragmatic Approach

Importance

Anemia is common in pregnancy, ranging from 5.4% in developed countries to more than 80% in developing countries. Anemia in pregnancy has been associated with prematurity, low birth weight, and adverse pregnancy outcomes.

Objective

This review uses clinical vignettes to illustrate the clinical presentations, approach to diagnosis, maternal and fetal implications, and treatment for the common etiologies of anemia in pregnancy.

Evidence Acquisition

Literature review.

Results

Normal physiological changes in pregnancy result in alterations of hematological parameters particularly in a reduction of hemoglobin (Hb) concentration. Consequently, the Hb used to define anemia in pregnancy is lower than in nonpregnant patients. As there is an increased requirement of iron in pregnancy, it is not unexpected that iron deficiency remains the most common cause of anemia and warrants a preemptive approach to prevent a further reduction in Hb. The syndromes associated with microangiopathic hemolytic anemia may pose a diagnostic challenge, as there are several potential etiologies that may be difficult to differentiate, and microangiopathic hemolytic anemia can be associated with significant maternal and fetal morbidity andmortality. Anemia secondary to sickle cell disease and autoimmune hemolytic anemiamerit special attention because there are risks secondary to red blood cell transfusion and risks to withholding transfusion.

Conclusions

Anemia in pregnancy is potentially associated with maternal and fetal adverse outcomes. Providing evidence-based care is essential to achieving the best pregnancy outcomes.

A Rare Case of Successfully Treated Coombs Negative Immune Haemolytic Anaemia in Pregnancy

Immune haemolytic anaemia in pregnancy, although rare, but it can be life threatening. Severe anaemia with jaundice, unresponsive to blood transfusion can clinch the diagnosis of immune haemolytic anaemia. Our patient was a 27-year-old second gravida, with all the above features, but there was diagnostic challenge as her Coombs test was negative. A high index of suspicion and rapid response to glucocorticoids, pointed towards the diagnosis. Thereafter, the course of pregnancy and postpartum period was uneventful. Thus, successful maternal and fetal outcome can be achieved with prompt diagnosis and treatment.

Pregnancy Induced Autoimmune Warm Antibodies Hemolytic Anemia: A Case Report

Background: Autoimmune haemolytic anaemia (AIHA), caused primarily by pregnancy, is poorly described in the literature. There is especially little information on coping with cases that are not responsive to glucocorticoid treatment, monitoring a fetal condition, and identifying fetal haemolytic anaemia as early as possible. Case: A case of pregnancy-induced autoimmune haemolytic anaemia is reported with major problems in differential diagnosis, treatment and the risks posed to both the mother and the fetus. The anaemia went into spontaneous remission of the disease several weeks after delivery. Conclusion: Autoimmune haemolytic anaemia is rarely reported in literature, but can be dangerous for both fetus and mother. It therefore should be described and discussed among obstetricians and gynaecologists, and the etiopathogenesis should be further studied.

Harmless Pregnancy-Induced Warm Autoantibodies to Red Blood Cells

Background

There is little information concerning the development and significance of autoantibodies (aab) to red blood cells (RBCs) during pregnancy.

Methods

Unselected pregnant women were routinely screened for the presence of unexpected antibodies to RBCs using standard techniques.

Results

Between 2009 and 2013, 153,612 pregnant women were tested. The antibody screening test was positive in 1,721 women (1.12%). In 1,602 (1.04%) cases, immune and/or non-immune alloantibodies and cold-reactive aab were detected, whereas warm-reactive aab were found in 119 women (0.08%). In almost all cases, warm-reactive aab belonged to the IgG class. No evidence of the presence of significant haemolysis in affected women was observed.

Conclusion

Pregnant women may rarely develop aab to RBCs, which do not appear to cause haemolytic anaemia. Further clarification is required on the reasons behind the development of these aab and their clinical insignificance.

Autoimmune hemolytic anemia

Red blood cell (RBC) autoantibodies are a relatively uncommon cause of anemia. However, autoimmune hemolytic anemia (AIHA) must be considered in the differential diagnosis of hemolytic anemias, especially if the patient has a concomitant lymphoproliferative disorder, autoimmune disease, or viral or mycoplasmal infection. Classifications of AIHA include warm AIHA, cold agglutinin syndrome, paroxysmal cold hemoglobinuria, mixed-type AIHA, and drug-induced AIHA. Characteristics of the autoantibodies are responsible for the various clinical entities. As a result, diagnosis is based on the clinical presentation and a serologic work-up. For each classification of AIHA, this review discusses the demographics, etiology, clinical presentation, laboratory evaluation, and treatment options.

In utero development of a warm-reactive autoantibody in a severely jaundiced neonate

BACKGROUND

The fetus and neonate are widely considered to be immunologically immature. However, there are rare case reports of RBC alloantibody and autoantibody development.

STUDY DESIGN AND METHODS

This report describes the case of a severely jaundiced full-term boy neonate presenting at birth with an IgG warm-reactive autoantibody.

RESULTS

Mother and neonate were both blood group A, D+. The mother had a negative antibody screen at 18 weeks' gestation and a negative DAT and antibody screen at the time of delivery. The neonate was born with a strongly reactive DAT (IgG) and a panreactive eluate. The serum also contained a panreactive antibody, and all crossmatches were incompatible. The neonate had a bilirubin of 12.5 mg per dL at birth, which peaked at 22.5 mg per dL. However, there was no overt evidence of hemolysis, as evidenced by normal serial Hct levels and reticulocyte counts. The neonate responded well to phototherapy and did not require either simple or exchange transfusion. The neonate's warm-reactive autoantibody maintained its original strength of reactivity on follow-up testing performed at 2 weeks and 2 months of age.

CONCLUSIONS

This report describes a rare case of apparent in utero RBC autoantibody development. The fetal/neonatal immune response to blood group antigens is reviewed.

Increased RBC autoantibody production in pregnancy

BACKGROUND

Autoimmunization against RBCs is generally believed to occur very rarely during pregnancy and to represent a high risk for those affected. The occurrence of benign RBC autoantibodies in pregnancy is reported.

STUDY DESIGN AND METHODS

The incidence of autoantibodies to RBCs in unselected pregnant and nonpregnant women were compared by the new standard gel hemagglutination method.

RESULTS

Data from a total of 22,782 pregnant and 12,903 nonpregnant women were analyzed. The antibody screen test was positive in 547 (2.40%) of the pregnant women. The positive test results were related to passive anti-D in 341 cases (1.50%), to clinically relevant alloantibodies in 43 cases (0.19%), to clinically irrelevant antibodies in 138 cases (0.61%), to autoantibodies in 23 cases (0.1%), and to autoantibodies plus alloantibodies in 2 cases (0.01%). In the cases of alloantibodies and/or autoantibodies, the DAT was invariably positive with anti-C3d and less commonly so with anti-IgG. The autoantibodies were first detected during pregnancy, they predominantly reacted with enzyme-treated RBCs, and none of the affected women or their infants appear to have developed clinically significant hemolysis. In the control group consisting of nonpregnant female blood donors, there were 3 cases (0.02%) of clinically insignificant IgG autoantibodies.

CONCLUSION

There is an increase in autoimmunization against RBCs during pregnancy. The resultant autoantibodies do not appear to cause significant RBC destruction. Further studies are required for precise characterization of this phenomenon.

[Danger of anti-erythrocyte antibodies during pregnancy]

INTRODUCTION

Red cell autoantibodies are very rarely observed in pregnant women. We report one case related to the presence of a lupus anticoagulant.

EXEGESIS

A 32-year-old woman had a history of two intrauterine deaths that had occurred at weeks 32 and 33, respectively. Due to the presence of a lupus anticoagulant, prednisone (20 mg/day) and subcutaneous calcium heparin were administered during her third pregnancy. The direct antiglobulin test remained positive throughout the pregnancy; however, hemolysis could not be detected. Caesarean section was done in emergency at week 29, due to fetal bradycardia related to severe fetal hemolysis.

CONCLUSION

When autoimmune hemolysis occurs during pregnancy, risks for the fetus increase with the severity of hemolysis in the mother. It is thought that child mortality reflects the existence of anemia, rather than the existence of hemolysis. Our observation suggests that severe fetal hemolysis may occur, despite the absence of hemolysis in the mother.

Clinical evaluation of a solid-phase test for red cell antibody screening of pregnant women

BACKGROUND

The aims of this study were to evaluate the results of a new solid-phase screening test for detecting atypical red cell (RBC) antibodies in a large number of pregnant women and to compare these results to the clinical outcome of the newborn.

STUDY DESIGN AND METHODS

A total of 38,700 infants born in Stockholm were studied retrospectively. Of these infants, 18,500 were born to pregnant women screened with the solid-phase test. Data were collected on all newborns with a positive direct antiglobulin test (DAT) and on infants requiring an exchange transfusion or a blood transfusion. These data were correlated to the screening results for the mothers.

RESULTS

Of 409 DAT-positive newborns, a serologic explanation for the positive DAT was found in 349. Three hundred four cases were due to ABO incompatibility between mother and child; 19 of these infants needed an exchange transfusion. Forty-two cases were due to unexpected maternal RBC antibodies; 11 of these infants were given an exchange transfusion. All 11 were identified before birth. Three other infants had DAT-positive tests due to ABO incompatibility and to unexpected maternal RBC antibodies.

CONCLUSION

ABO incompatibility is a major indication for exchange transfusion in DAT-positive newborns. There was no evidence that the solid-phase screening test had failed to detect any clinically significant RBC antibodies. Finally, the results of this study do not indicate a need for routine screening of D+ women more than once during each pregnancy.

Autoimmune hemolytic anemia

Immune hemolytic anemia can be either isoimmune or autoimmune. Autoimmune hemolytic anemias (AIHA) consist of group of disorders whose common characteristics are the presence of an antibody which in turn causes short red blood cell (RBC) life. The rate and site of hemolysis and hence the clinical manifestations depends on the type of antibody attached and its propensity to fix complement. Antibodies of the IgG class are most commonly responsible for AIHA in children. Rh erythrocyte antigen is involved in more than 70% of cases. Since the antibody has its maximal activity at 37 degrees C, the resultant hemolysis is called warm antibody induced hemolytic anemia. This is a severe life threatening condition, the clinical features are: sudden onset of pallor, jaundice and dark urine. The cornerstone of diagnosis is a positive Coomb's antiglobulin test in the presence of hemolysis. Coomb's test has false negative and false positive rates in about 2-4% and 8% of all cases respectively. The modalities for treatment of warm AIHA include blood transfusion, steroid therapy, intravenous gammaglobulin, plasma-pheresis and splenectomy. The choice depends on the severity of the disease and child's response to therapy.

Autoimmune haemolytic anaemia during pregnancy

We describe a 31-year-old woman, who presented during her first pregnancy, with severe haemolytic anaemia due to auto-immune antibodies against erythrocytes. IgG warm-antibodies, as well as IgM antibodies were found in her serum. This idiopathic form of auto-immune haemolysis was successfully treated with glucocorticoids. During her second pregnancy auto-immune haemolysis again developed and was treated similarly. Two healthy children were born. The uneventful outcome we saw with our patient is in keeping with other reports in the literature.

Erythrocyte autoantibodies, the monocyte monolayer assay and in vivo haemolysis

Monocyte monolayer assays (MMA) were performed using red cells (RBCs) from 159 patients with a positive direct antiglobulin test and monocytes from healthy individuals. The results of the MMA reflected, to a great extent, in vivo haemolysis; 56/63 patients with a positive result, but only 10/96 with a negative one, had evidence of in vivo RBC destruction. Positive MMAs were observed with autoantibodies of all types: warm (42 cases), cold (14 cases), mixed (seven cases), but never in patients with only C3d on their RBCs and no detectable autoantibodies. With warm autoantibodies, the MMA results depended, in part, on the level of IgG sensitization; additional C3d coating acted synergistically to lower the amount of IgG necessary for monocyte interaction to occur. The presence of IgG3 as well as IgG1 on the RBCs was usually associated with a high MMA result; most of these cases, however, also exhibited larger amounts of cell-bound IgG. When the MMA results were analysed in respect of the various types of autoantibodies, differences in the phagocytosis:adherence ratio were observed; in patients with warm autoantibodies, there was a preponderance of phagocytosis, whereas in those with cold and mixed types, adherent RBCs predominated or were found alone.

Autoimmune haemolytic anaemia in pregnancy: a case report

A young primigravida had idiopathic warm antibody (IgG) autoimmune haemolytic anaemia (AIHA) occurring in the third trimester of pregnancy. Her haemolytic process was responsive to steroid therapy and no transfusion was needed. She delivered a healthy baby with no evidence to haemolysis, though his red cells were coated with IgG which was probably of maternal origin.

Erythrocyte autoantibodies, subclasses of IgG and autoimmune haemolysis

The subclass pattern of red cell bound IgG autoantibody was studied in 304 patients on 426 occasions. Subclass interrelationships with time, other cell bound immunoglobulins (IgM, IgA), amount of bound IgG and serum haptoglobin levels were investigated using population proportions; because of the multiple statistical tests, P less than 0.01 was required for significance. IgG1 was most common, being found in 98% of cases and as the sole subclass in 64%; multiple subclasses occurred in 34.5%. The IgG subclass pattern possibly changed with time (P less than 0.02, greater than 0.01), populations being compared at 6 and 12 months. There was a highly significant and important correlation between multiple IgG subclasses and multiple immunoglobulin coating; in our further studies, this necessitated the use of samples where only cell bound IgG was increased. Multiple IgG subclasses strongly correlated with larger amounts of cell bound IgG, groups with greater than 2 and less than 1 OD units by the enzyme-linked direct antiglobulin test being compared (approximately greater than 800 and less than 400 molecules IgG per red cell respectively). Multiple subclasses (P less than 0.05, greater than 0.01), but not IgG3, were possibly associated with low haptoglobin levels; significance was reached, however, if the multiple immunoglobulin effect was ignored. IgG subclass interrelationships are clearly complex and require strictly defined populations for their study.

Erythrocyte autoantibodies, autoimmune haemolysis, and myelodysplastic syndromes

Immunohaematological investigations were carried out in 46 patients with erythrocyte autoantibodies associated with myelodysplastic syndromes. Eight patients had refractory anaemia, 17 refractory anaemia with ring sideroblasts, 11 refractory anaemia with excess of blasts, four chronic myelomonocytic leukaemia, five refractory anaemia with excess of blasts in transformation and one could not be classified. Standard agglutination direct antiglobulin tests showed that the red cells were most often coated with IgG and C3d, though increased amounts of IgM or IgA were also found in 15 of 35 cases (43%) when the more sensitive enzyme linked method was used. The IgG antibodies were predominantly of IgG1 subclass. Clinically important autoimmune haemolysis occurred in 15 patients, and was of "warm", "cold," and "mixed" types in seven, four, and four cases, respectively: it is important to recognise its presence in view of the good response to treatment. The increased incidence of erythrocyte autoantibodies in myelodysplastic syndromes is thought to be one manifestation of disturbed immune homeostasis.

Patients with red cell autoantibodies: selection of blood for transfusion

The provision of blood for transfusing patients whose sera contain red cell autoantibodies requires considerable expertise. Over 8 years, 3888 samples from 2149 patients were examined; the varying clinical presentation necessitated a flexible investigative approach. The autoantibodies showed evidence of blood group specificity in 706 patients (32.9%), usually within the Rh system for warm reacting antibodies, whereas cold antibodies were mostly anti-I. Concomitant alloantibodies were detected by noting varying reaction strengths during antibody investigation and compatibility testing, and by absorption techniques using autologous or selected allogenous red cells. Alloantibodies were found in 294 patients (13.7%); the most frequent were anti-E and anti-K. Compatibility tests were performed on SAG-M donor blood of suitable ABO group, similar Rh genotype, Kell negative and lacking antigens to any alloantibodies detected. All units of blood were incompatible by at least one technique and were issued as 'not compatible but considered suitable'. A total of 7052 units was issued for 1685 patients; no haemolytic reactions were reported. It was concluded that blood can be safely given to patients with autoantibodies, even in serologically complex cases, providing adequate investigations are carried out.

Autoimmune hemolysis: a critical review

Autoimmune hemolysis is defined as a shortening of erythrocyte lifespan due to antibodies directed against the individuals own red cells. This autoantibody production (by B lymphocytes) is thought to result from deficient activity of suppressor T lymphocytes. The rate of erythrocyte destruction depends on the properties of the autoantibodies and on the activities of the complement and mononuclear phagocyte systems: anemia results when destruction outweighs marrow production. Autoimmune hemolysis, which may be primary or secondary, is classified into "warm," "cold," and "mixed" types. The hemolysis associated with pregnancy. Donath-Landsteiner antibodies, of mixed type, and in children, is treated in detail. Current treatment is with immunosuppressive drugs, surgery, and plasma exchange, though immunomanipulation may become important in the future; blood transfusion may be a life-saving adjunct to other therapy.