Autoimmune hemolytic anemia in children. A review of 80 cases

How to use Donath-Landsteiner test to diagnose paroxysmal cold haemoglobinuria (PCH)

Paroxysmal cold haemoglobinuria (PCH) accounts for around a third of cases of autoimmune haemolytic anaemia in children. PCH is caused by an autoantibody that fixes complement to red cells at low temperatures and dissociates at warmer temperatures (a biphasic haemolysin), triggering complement-mediated intravascular haemolysis. Named the Donath-Landsteiner (D-L) antibody after its discoverers, it is usually formed in response to infection and demonstrates specificity for the ubiquitous red cell P-antigen. A D-L test can be used to detect the presence of the D-L autoantibody in the patients' serum. Here we discuss the use of the D-L test in identifying PCH in a 2-year-old boy who presented with haemolytic anaemia. A summary of the key information can be found in the infographic.

Warm autoimmune haemolytic anaemia seen in association with primary sclerosing cholangitis in the setting of Klebsiella pneumoniae bacteraemia

Warm autoimmune haemolytic anaemia mediated by warm agglutinins is a rare and heterogeneous disease which can be idiopathic or secondary to an underlying disease. Primary sclerosing cholangitis is a chronic autoimmune cholangiopathy that is very rarely associated with haemolytic anaemia. Infections can also act as triggers for immune haemolytic anaemia. Here, we report a case of a woman in her 50s with a history of primary sclerosing cholangitis and a positive direct antiglobulin test with no evidence of haemolysis who developed overt warm autoimmune haemolytic anaemia in the setting of cholangitis and Klebsiella pneumoniae bacteraemia. She was treated conservatively with appropriate antibiotics and cautious red blood cell transfusion with complete resolution of haemolysis; immunosuppression was avoided given sepsis on presentation. This case highlights a rare association of warm immune haemolytic anaemia in the setting of K. pneumoniae bacteraemia and the role of a tailored treatment approach to treat this heterogeneous disease.

Autoimmune Hemolytic Anemia in the Pediatric Setting

Autoimmune hemolytic anemia (AIHA) is a rare disease in children, presenting with variable severity. Most commonly, warm-reactive IgG antibodies bind erythrocytes at 37 °C and induce opsonization and phagocytosis mainly by the splenic macrophages, causing warm AIHA (w-AIHA). Post-infectious cold-reactive antibodies can also lead to hemolysis following the patient’s exposure to cold temperatures, causing cold agglutinin syndrome (CAS) due to IgM autoantibodies, or paroxysmal cold hemoglobinuria (PCH) due to atypical IgG autoantibodies which bind their target RBC antigen and fix complement at 4 °C. Cold-reactive antibodies mainly induce intravascular hemolysis after complement activation. Direct antiglobulin test (DAT) is the gold standard for AIHA diagnosis; however, DAT negative results are seen in up to 11% of warm AIHA, highlighting the need to pursue further evaluation in cases with a phenotype compatible with immune-mediated hemolytic anemia despite negative DAT. Prompt supportive care, initiation of treatment with steroids for w-AIHA, and transfusion if necessary for symptomatic or fast-evolving anemia is crucial for a positive outcome. w-AIHA in children is often secondary to underlying immune dysregulation syndromes and thus, screening for such disorders is recommended at presentation, before initiating treatment with immunosuppressants, to determine prognosis and optimize long-term management potentially with novel targeted medications.

Primary IgA-mediated Autoimmune Hemolytic Anemia in an Infant Successfully Treated With Rituximab

Autoimmune hemolytic anemia (AIHA) is uncommon in the pediatric population and is often associated with an infectious etiology or postvaccination. Mostly, the child presents with a positive direct antiglobulin test. The diagnosis can be challenging, as in our case with an immunoglobulin A-mediated AIHA. In addition to supportive therapy, such as a red blood cell transfusion, steroids are the first choice of treatment. Rituximab, as second-line treatment, can be given in conjunction. We report the first case of immunoglobulin A-mediated AIHA treated with rituximab in the literature.

Reliable assessment of the incidence of childhood autoimmune hemolytic anemia

BACKGROUND

Childhood autoimmune hemolytic anemia (AIHA) is a rare and severe disease characterized by hemolysis and positive direct antiglobulin test (DAT). Few epidemiologic indicators are available for the pediatric population. The objective of our study was to reliably estimate the number of AIHA cases in the French Aquitaine region and the incidence of AIHA in patients under 18 years old.

PROCEDURE

In this retrospective study, the capture-recapture method and log-linear model were used for the period 2000-2008 in the Aquitaine region from the following three data sources for the diagnosis of AIHA: the OBS'CEREVANCE database cohort, positive DAT collected from the regional blood bank database, and the French medico-economic information system.

RESULTS

A list of 281 different patients was obtained after cross-matching the three databases; 44 AIHA cases were identified in the period 2000-2008; and the total number of cases was estimated to be 48 (95% confidence interval [CI]: 45-55). The calculated incidence of the disease was 0.81/100,000 children under 18 years old per year (95% CI 0.76-0.92).

CONCLUSION

Accurate methods are required for estimating the incidence of AIHA in children. Capture-recapture analysis corrects underreporting and provides optimal completeness. This study highlights a possible under diagnosis of this potentially severe disease in various pediatric settings. AIHA incidence may now be compared with the incidences of other hematological diseases and used for clinical or research purposes.

Diagnosis and management of newly diagnosed childhood autoimmune haemolytic anaemia. Recommendations from the Red Cell Study Group of the Paediatric Haemato-Oncology Italian Association

Autoimmune haemolytic anaemia is an uncommon disorder to which paediatric haematology centres take a variety of diagnostic and therapeutic approaches. The Red Cell Working Group of the Italian Association of Paediatric Onco-haematology (Associazione Italiana di Ematologia ed Oncologia Pediatrica, AIEOP) developed this document in order to collate expert opinions on the management of newly diagnosed childhood autoimmune haemolytic anaemia.The diagnostic process includes the direct and indirect antiglobulin tests; recommendations are given regarding further diagnostic tests, specifically in the cases that the direct and indirect antiglobulin tests are negative. Clear-cut definitions of clinical response are stated. Specific recommendations for treatment include: dosage of steroid therapy and tapering modality for warm autoimmune haemolytic anaemia; the choice of rituximab as first-line therapy for the rare primary transfusion-dependent cold autoimmune haemolytic anaemia; the indications for supportive therapy; the need for switching to second-line therapy. Each statement is provided with a score expressing the level of appropriateness and the agreement among participants.

Recurrent Donath-Landsteiner hemolytic anemia: a pediatric case report

BACKGROUND

Paroxysmal cold hemoglobinuria (PCH) is a form of autoimmune hemolytic anemia caused by the Donath-Landsteiner antibody (D-L antibody). In children, this is typically a transient immune-mediated hemolysis that follows a viral illness and does not recur. Recurrent acute or chronic PCH due to D-L antibody is very rare.

CASE REPORT

We have reported a unique case of recurrent PCH in a 5-year-old boy with two acute episodes of hemolysis separated by 21 months of hematologic remission. Each episode was severe requiring red blood cell transfusions, intravenous methylprednisolone, and intravenous immunoglobulin during the second episode. Testing identified recurrence of the D-L antibody with the classic anti-P biphasic hemolysis.

CONCLUSION

This demonstrates that PCH can be a recurrent disease in the pediatric population (in the absence of syphilis) with the classical D-L antibody.

The Clinical Pictures of Autoimmune Hemolytic Anemia

Autoimmune hemolytic anemia is characterized by shortened red blood cell survival and a positive Coombs test. The responsible autoantibodies may be either warm reactive or cold reactive. The rate of hemolysis and the severity of the anemia may vary from mild to severe and life-threatening. Diagnosis is made in the laboratory by the findings of anemia, reticulocytosis, a positive Coombs test, and specific serologic tests. The prognosis is generally good but renal failure and death sometimes occur, especially in cases mediated by drugs.

Diagnostic and therapeutic challenges of primary autoimmune haemolytic anaemia in children

Autoimmune haemolytic anaemias (AIHAs) are extracorpuscular haemolytic anaemias produced by antierythrocyte autoantibodies which cause a shortened red blood cell life span. There are several reasons why the diagnosis and treatment of AIHAs in children represent a bigger challenge than in adult patients, including the presence of particular AIHA types, the uncertainty of serological tests and the limited clinical experience. All these facts have added up to a poor understanding and management of some topics in childhood AIHA. We discuss some of these questions, for example, the occurrence of AIHA with negative direct antiglobulin (Coombs) test, the correct diagnosis and actual incidence of paroxysmal cold haemoglobinuria, the most appropriate second-line therapy of AIHA in childhood or the management of transfusion procedures in these patients. This review takes a practical point of view, providing with some ground rules on how to identify and deal with these paediatric patients.

Disseminated intravascular coagulation due to IgM-mediated autoimmune hemolytic anemia

Disseminated intravascular coagulation (DIC) due to red cell hemolysis has been previously attributed to transfusion-related hemolytic reactions, but not to autoimmune hemolytic anemia. We report a case of DIC in a child with complement-fixing IgM-mediated cold-agglutinin autoimmune hemolysis, which resulted in arterial thrombosis and gangrene of the upper and lower extremities.

IgA-mediated autoimmune hemolytic anemia in an infant

Autoimmune hemolytic anemia (AIHA) is characterized by the presence of autoantibodies, most frequently of the IgG isotype, directed against erythrocyte surface antigens. The direct antiglobulin test (DAT) is the critical laboratory test for the diagnosis of AIHA, but is negative in 3-11% of cases. In these cases of DAT negative AIHA, a wider spectrum of clinical data including more specialized testing for erythrocyte autoantibodies may be required. We describe the unique and challenging case of an infant with corticosteroid-responsive, DAT negative AIHA, in which specialized gel card testing identified an isolated IgA autoantibody on the erythrocyte surface.

New insights into childhood autoimmune hemolytic anemia: a French national observational study of 265 children

BACKGROUND

Autoimmune hemolytic anemia is a rare condition in children. Little is known about its initial presentation and the subsequent progression of the disease.

DESIGN AND METHODS

Since 2004, a national observational study has been aiming to thoroughly describe cases and identify prognostic factors. Patients from all French hematologic pediatric units have been included if they had a hemoglobin concentration less than 11 g/dL, a positive direct antiglobulin test and hemolysis. Evans' syndrome was defined by the association of autoimmune hemolytic anemia and immunological thrombocytopenic purpura. Data from patients' medical records were registered from birth to last follow-up. Autoimmune hemolytic anemia was classified as primary or secondary. Remission criteria, qualifying the status of anemia at last follow-up, were used with the aim of identifying a subgroup with a favorable prognosis in continuous complete remission.

RESULTS

The first 265 patients had a median age of 3.8 years at diagnosis. In 74% of cases the direct antiglobulin test was IgG/IgG+C3d. Consanguinity was reported in 8% of cases and first degree familial immunological diseases in 15% of cases. Evans' syndrome was diagnosed in 37% of cases. Autoimmune hemolytic anemia was post-infectious in 10%, immunological in 53% and primary in 37% of cases. After a median follow-up of 3 years, 4% of children had died, 28% were still treatment-dependent and 39% were in continuous complete remission. In multivariate analysis, IgG and IgG+C3d direct antiglobulin tests were associated with a lower rate of survival with continuous complete remission (adjusted hazard ratio, 0.43; 95% confidence interval, 0.21-0.86).

CONCLUSIONS

This nationwide French cohort is the largest reported study of childhood autoimmune hemolytic anemia. The rarity of this condition is confirmed. Subgroups with genetic predisposition and underlying immune disorders were identified.

Thrombocytopenia and anemia in infants and children

Thrombocytopenia and anemia are the two most common hematologic conditions seen in the pediatric emergency department. Providers of emergency pediatric care must have an understanding of the causes and therapies for the various conditions that result from thrombocytopenia and anemia. This article reviews the common causes of isolated thrombocytopenia and anemia in infancy and childhood.

A 13-year-old girl with cold agglutinin syndrome caused by anti-i

A 13-year-old girl with cold agglutinin syndrome caused by anti-i was serologically positive for Epstein-Barr virus. The anti-i had a high titer at 4 degrees C and high thermal amplitude (reacting up to 37 degrees C with both cord i RBCs and the patient's autologous RBCs). The patient's hemoglobin dropped to 48 g/L. The age of the patient, the severity of the hemolysis, and the antibody specificity were unusual features of cold agglutinin syndrome. Transfusions with adult (I) red blood cells were effective.

Hemolytic anemia due to warm autoantibodies

The diagnosis of autoimmune hemolytic anemia (AHA) requires evidence of shortened red blood cell (RBC) survival mediated by autoantibodies directed against autologous RBCs. About 80 percent of patients with AHA have warm-reactive antibodies of the IgG isotype; the remainder exhibit cold-reactive autoantibodies. Typical patients exhibit anemia, reticulocytosis, spherocytes and polychromasia on the blood film and a positive direct antiglobulin test (DAT). Increased indirect serum bilirubin, urinary urobilinogen and serum lactate dehydrogenase (LDH), and decreased serum haptoglobin are not required for the diagnosis, but are frequently present. Patients with AHA and no underlying associated disease are said to have primary or idiopathic AHA. AHA in patients with associated autoimmune disease and certain malignant or infectious diseases is classified as secondary. The etiology of AHA is unknown. Patients with symptomatic anemia require transfusion of RBCs. Prednisone and splenectomy may provide long term remission. Rituximab, intravenous immunoglobulin, immunosuppressive drugs and danazol have been effective in refractory cases and for patients who are poor candidates for surgery.

Warm-reactive autoantibodies in pediatric patients: clinical and serologic correlations

The significance of warm-reactive autoantibodies in pediatric patients has not been a subject of thorough evaluation. This study was undertaken to correlate the clinical and serologic features of these antibodies to identify predictors of clinical significance. Forty-two consecutive patients with serologically detectable warm-reactive autoantibodies were studied. These patients (21 male, 21 female) had a mean age of 9 years (range: 2 mo to 21 y). Primary diagnoses included autoimmune disorders (14), sickle cell disease (14), viral infection (4), idiopathic autoimmune hemolytic anemia (2), leukemia (2), and other diseases (6). Autoimmune hemolysis, as determined by clinical and laboratory findings, was documented in 24 patients (57%). Serologic studies revealed that all patients demonstrated IgG on their red cells [Direct Antiglobulin Test (DAT) reactivity range: microscopic to 3+]; 17 (40%) also demonstrated complement (DAT reactivity range: microscopic to 2+). There was a correlation between the strength of the DAT for IgG and the presence of complement on the red cells, with both being important predictors of hemolysis. These findings may be useful in predicting the clinical significance of warm-reactive autoantibodies in pediatric patients and allow for more efficient and effective follow-up care.

Autoimmune hemolytic anemia in childhood: serologic features in 100 cases

BACKGROUND

Red blood cell (RBC) autoimmunization is a relatively uncommon cause of anemia in children and presents some differences from those of adults. Due to its frequency, autoimmune hemolytic anemia (AIHA) in childhood has prompted very few studies, and the literature consists mostly of sporadic case histories. The objective of this study was to stress the importance of an appropriate serologic diagnosis in suspected cases.

STUDY DESIGN AND METHODS

This report describes the immunohematologic features of 100 patients with AIHA studied in the Immunohaematologic Unit of Blood Bank, "La Sapienza" University of Rome. The patients were diagnosed in the same department from 1983 to 2003.

RESULTS

The peak incidence of AIHA was in the first 4 years of life. No sex predominance was noted. Warm AIHA was the most common type of acquired immune hemolytic anemia; it comprised 64 of the 100 patients, whereas 26 patients showed a cold AIHA. Associated AIHA showed a slightly more frequent incidence (54/100) compared to idiopathic forms of AIHA (46/100).

CONCLUSIONS

In this study serologic records of 100 children with confirmed AIHA are reported. This series, much larger than any previously reported, is critically reviewed and analyzed to delineate the immunologic features of the disease in childhood.

Transient thrombocytopenia after incompatible red blood transfusion in an infant girl with autoimmune hemolytic anemia

We report on 5-month-old girl with severe autoimmune hemolytic anemia (hemoglobin 2.9 g/dl, positive direct Coombs test) in whom thrombocytopenia developed after red blood cell transfusion. The platelet count was 62.1 x 10(4)/mm3 on admission and rapidly fell to 6.0 x 10(4)/mm3 rapidly after transfusion of incompatible red blood cells with intravenous predonisolone administration. No increased hemolysis or alloimmunization was observed after transfusion. The platelet count and hemoglobin levels gradually improved over 8 weeks with corticosteroid therapy. We suspect that the thrombocytopenia in our patient was transfusion-induced.

Autoimmune hemolytic anemia preceding T-ALL in a five-year-old girl

A 5-year-old girl developed acute lymphoblastic leukemia (T-ALL) 15 months after being diagnosed with autoimmune hemolytic anemia (AHA), while AHA was in partial remission. AHA was mediated by warm antibodies. Because AHA could not be controlled during the induction therapy of ALL, she was administered immunoglobulin G and plasmapheresis was performed. Hepatomegaly dissappeared in the 4th month. However, anemia requiring blood transfusion, positive direct Coombs' test, and splenomegaly dissappeared in the 13th month of the leukemia treatment; reticulocytosis and decreased haptoglobin level persisted. AHA exacerbated in the 24th month of the ALL therapy. Prednisolone was started but the family refused to continue the therapy. This case presents some features that were not reported before, such that ALL was preceded by AHA and involved T-cell lineage, AHA was mediated by warm antibodies, and the two disorders took place in childhood.

[Autoimmune hemolytic anemia with complement-positive direct antiglobulin test]

Autoimmune hemolytic anemia (AIHI) is an infrequent disease in the pediatric age group. Its diagnosis is given by the direct antiglobulin test (DAT) or Coombs' test, which determines which type of globulin (IgG or complement) is the cause of the hemolysis. The type of globulin involved determines the etiology of AIHI, which is usually confirmed by positive results of other laboratory investigations such as cold agglutinin determination or the Donath-Landsteiner test. We present three cases of AIHI. DAT was positive to complement with diverse etiology: warm antibody with IgG-negative DAT, cold agglutinins associated with infectious mononucleosis, and Doth-Landsteiner antibodies. In all patients, empirical treatment with corticosteroids was initiated. The treatment was withdrawn or continued, depending on the final etiology of AIHI.

[Characteristics of autoimmune hemolytic anemia in adults: retrospective analysis of 83 cases]

PURPOSE

To describe the main characteristics and outcome of adult's acquired immune hemolytic anemias (AIHA). To analyse the relevance of the complementary tests performed for the search of an underlying disease.

METHODS

Retrospective (1980-2000) monocentric study.

INCLUSION CRITERIA

age above 16, AIHA defined by an hemoglobin level below 12 g/dl in men and 11 g/dl in women, with hemolysis and/or a positive direct Coombs test and/or the presence of cold agglutinins (threshold 1/500) and/or in the absence of any other cause.

RESULTS

Eighty three patients included (56 women and 27 men), with a mean age of 56 years (+/- 22) at AIHA onset including: 72 patients (87%) with warm antibody AIHA and 11 (13%) with cold agglutinin disease. The mean follow-up was 48 months (median 22 months). Among the 72 patients with warm antibody AIHA, the specificity of autoantibodies was: IgG + complement (43%), IgG (32%) or complement alone (25%); cold agglutinins (titre from 1/60 to 1/512) were detected in 15 (20%) of the patients. Antinuclear antibodies were detected (threshold: 1/80) in 33% of the cases. Hypogammaglobulinemia on serum protein electrophoresis (SPE) was significantively associated with the presence of an underlying non-Hogkin lymphoma (NHL). The CT-scan of the the chest and abdomen which was performed in 50% of the patients, showed abnormalities other than a spleen enlargement in 25% of the cases. The medullar biopsy (MB) was abnormal in 7 of 26 cases (27%) but lead by itself to the diagnosis of NHL in a single case. Thrirty seven (51%) of warm antibody AIHA cases were finally considered to be "secondary" to an underlying disease namely: NHLs (n = 14), Hogkin's disease (n = 1) connective tissue disease (CTD) (n = 14), drug-induced AIHA (n = 3), miscellaneous (n = 5). In 6 out of 14 cases (43%) of NHL's associated AIHA, the onset of AIHA precedes the NHL from 22 to 66 months. The response rates to different therapeutic regimens did not significatively differ when "secondary" and "idiopathic" AIHA were compared. Overall, 13 patients (15.6%) died mainly from infectious complications (n = 5) or an underlying NHL (n = 5).

CONCLUSIONS

In more than half of the cases AIHA are associated with an underlying disease and AIHA may precede the onset of a NHL for a long period. In the absence of a clinically apparent underlying disorder, testing for the presence of antinuclear antibodies, a SPE and a CT-scan must be systematic. Conversely, if no abnormalities are found, the relevance of a systematic MB at AIHA onset seems very low.

Resolution of severe Donath-Landsteiner autoimmune hemolytic anemia temporally associated with institution of plasmapheresis

OBJECTIVES

To report a case of severe postinfectious autoimmune hemolytic anemia (AIHA) owing to the Donath-Landsteiner (DL) antibody resolving with plasmapheresis, and to review the pathophysiology of this underrecognized cause of pediatric AIHA and its potential susceptibility to plasmapheresis therapy.

DESIGN

Descriptive case report.

SETTING

A pediatric intensive care unit in a university children's hospital.

PATIENT

A 5-yr-old Hispanic female had gastroenteritis followed by progressive intravascular hemolysis, initially attributed to acute postinfectious cold hemagglutinin (immunoglobulin M) disease.

INTERVENTION

With no slowing in the rate of hemolysis, a continued need for frequent transfusions, and a lack of response to corticosteroid and intravenous immunoglobulin therapy, a 3-day course of plasmapheresis was administered.

MEASUREMENTS AND MAIN RESULTS

The patient presented to an emergency department with an initial hematocrit of 22%, which fell to 12% by hospital admission. She received nine transfusions over 7 days, with her hematocrit reaching a nadir of 11% on the 5th day of hospitalization. Once plasmapheresis was initiated, she required no further transfusion. Analysis of serum from initial presentation demonstrated biphasic hemolysis, confirming the presence of the DL antibody.

CONCLUSIONS

In AIHA, in which the direct antiglobulin test detects primarily C3 rather than immunoglobulin G, especially in children, the DL antibody must be considered. Confirming the diagnosis rapidly may be critical, especially in cases of severe hemolysis, because this may help direct therapy. A low titer of DL antibody can mediate severe intravascular hemolysis given its propensity to sensitize, detach, and rebind erythrocytes with changes in temperature in the microcirculation. However, given the transient and relatively brief production of the DL antibody in postviral illness, early clearance of the offending antibody may be possible with plasmapheresis, without the expectation for significant rebound antibody production, potentially decreasing the length of hospital stay and the need for transfusions.

Autoimmune hemolytic anemia caused by IgG lambda-monotypic cold agglutinins of anti-Pr specificity after rubella infection

BACKGROUND

In postinfection cold agglutinin (CA) disease, a relation between CA specificity and the underlying infectious agent has been observed. The induction of anti-I by Mycoplasma pneumoniae and that of anti-i by EBV are well-established examples.

CASE REPORT

A 5-year-old boy developed severe hemolytic anemia after serologically ascertained rubella infection. Hemolysis was caused by high-titer CAs, which were analyzed by absorption and elution with sialidase-treated RBCs and hemagglutination-inhibition experiments.

RESULTS

After elimination of normal anti-I and anti-T, the predominant CA was found to be an IgG lambda autoantibody with anti-Pr(1) specificity.

CONCLUSION

This case seems to be of interest because it is the first report of severe CA-induced hemolysis after rubella infection, it is the first description of an IgG lambda-monotypic CA, and, along with previous case reports (three established and three suspected cases), it indicates a relationship between rubella infection and the CA specificity anti-PR:

Vaccination-associated immune hemolytic anemia in two children

BACKGROUND

Two children in whom acute autoimmune hemolytic anemia (AIHA) developed after vaccination were studied.

CASE REPORTS

The children were a 20-month-old girl and a 21-month-old boy. The diagnosis of AIHA was made in accordance with established criteria (hemolysis, positive DAT, and lack of other reasons for the hemolysis). Serologic tests were performed according to standard technique.

RESULTS

The girl experienced two attacks of hemolysis. The first episode occurred 2 weeks after oral polio vaccination, and the second episode was observed 7 months later, when she received a simultaneous vaccination against mumps, rubella, and measles. The DAT was strongly positive with anti-C3d. No autoantibodies were detectable in either episode. The boy experienced acute hemolysis a few days after a simultaneous revaccination against diphtheria-pertussis-tetanus, Haemophilus influenzae, hepatitis B, and polio. The DAT using anti-IgG was strongly positive, and the DAT performed with anti-C3d was weakly positive.

CONCLUSION

Vaccination-induced AIHA resembles those forms of AIHA related to infectious diseases, and it may occur more frequently than has been reported.

Intensive plasma exchange for severe autoimmune hemolytic anemia in a four-month-old infant

We report the smallest infant (7.5 kg) to receive intensive plasma exchange (52 PEs) therapy as treatment of autoimmune hemolytic anemia (AIHA). PE temporarily reduces circulating autoantibody levels and can be an effective adjunctive therapy with corticosteroids and cytotoxic drugs or other immuno-suppressants. Although his clinical course was prolonged and complicated by cytomegalovirus infection with spontaneous perforation of his colon, his recovery was complete. He has remained healthy for more than 2 years. Because of his small size, calcium gluconate was added to replacement fluids and calcium levels closely monitored. The apheresis machine and tubing were routinely primed with red blood cells and FFP substituted for 5% human albumin during the second half of all procedures to maintain adequate levels of procoagulant. Our experience suggests that intensive PE is helpful in controlling severe AIHA and should be considered even for very small patients.

The spectrum of Evans' syndrome

Eleven patients (10 boys, one girl) with Evans' syndrome with a median follow up time of 8.0 years were evaluated retrospectively. Six patients had either persistent hepatosplenomegaly or generalised lymphadenopathy, or both. In five patients, an increase in lymph node and/or spleen size was observed during the exacerbations of cytopenias. Seven patients had quantitative serum immunoglobulin abnormalities at the time of presentation. There were associated systemic manifestations in nine patients. Various forms of treatment were used with mixed results. Four patients died from sepsis and haemorrhage; four had complete recovery--two after splenectomy. These findings show that Evans' syndrome is a heterogeneous disorder with significant morbidity and mortality. High incidence of quantitative serum immunoglobulin abnormalities, lymphoid hyperplasia, and associated systemic manifestations suggest that Evans' syndrome may represent a stage of a more broad spectrum, generalised immune dysregulation.

Acute transient hemolytic anemia with a positive Donath-Landsteiner test following parvovirus B19 infection

PURPOSE

A case of childhood acute hemolytic anemia following parvovirus infection provided an hypothesis for the high frequency of Donath-Landsteiner antibodies and inappropriately low reticulocyte counts in this disease.

PATIENTS AND METHODS

A 3-year-old boy with hematuria and jaundice was found to have autoimmune hemolytic anemia due to a biphasic IgG Donath-Landsteiner antibody. Despite profound anemia (hematocrit 14.5%), the reticulocyte count was low (1.0%) and examination of his normocellular bone marrow showed erythroid hypoplasia.

RESULTS

A clinical diagnosis 2 weeks earlier of acute parvovirus B19 was serologically confirmed as the associated antecedent infection. Hemolytic anemia resolved with packed red cell transfusion, and intravenous immune globulin and steroid treatment.

CONCLUSIONS

The high-frequency red cell P antigen is both the unusual specificity of Donath-Landsteiner antibody and the viral receptor for parvovirus infection of red cell precursors. We speculate that interaction of the virus with its receptor may change antigenicity such that anti-P autoantibody forms. Parvovirus B19 may be a primary cause of reticulocytopenic postinfectious hemolytic anemia in children.

Severe low-titer cold-hemagglutinin disease responsive to steroid pulse therapy

We report the case of a 12-year-old boy suffering from severe low-titer cold-hemagglutinin disease with excruciating colicky abdominal pain, jaundice, and acute hemolytic anemia requiring transfusion. Cold hemagglutinins of the IgM type and a positive direct antiglobulin test, predominantly against C3d, were found. Steroid pulse therapy with 20 mg/kg body wt. methylprednisolone for 3 consecutive days was given. Abdominal pain disappeared within 12 h of the first steroid infusion and hemolysis was halted. We conclude that a therapeutic trial with steroid pulse therapy in severe low-titer cold-hemagglutinin disease is warranted.

The acute infection-associated hemolytic anemia of childhood: immunofluorescent detection of microbial antigens altering the erythrocyte membrane

The majority of acute infection-associated hemolytic diseases of infancy and childhood have been suggested to be caused by exogenic alterations of the erythrocyte surface, though laboratory methods for their further evaluation were not yet available. Investigating 96 children, the present study characterizes 72% of cases as corresponding to this type of acute acquired hemolytic anemia, which cannot be clearly related to autoantibodies against unmodified components of the host's own red cells. Using a new immunofluorescence test, the erythrocyte membrane of 80% of these children was found to be altered in vivo by nonspecific adsorption of foreign material released from the infectious micro-organisms. In 24% of cases additive binding of complement was detectable by an antiglobulin test. Thus, the adsorption of microbial antigens to the red cell surface is suggested to be one of the causes for the removal of altered erythrocytes due to phagocytosis or a complement-dependent destruction during the course of infection-associated hemolytic anemia. Especially in childhood, the immunofluorescent detection of an erythrocyte sensitization in vivo provides a further characterization of this type of mostly transient hemolytic disease, which probably can be treated without any immunosuppressive drug, merely by elimination of the underlying infection.

Red blood cell transfusion in warm-type autoimmune haemolytic anaemia

Blood transfusions are regarded as hazardous in patients with warm-type autoimmune haemolytic anaemia (AIHA) because of potential intensification of haemolysis and a presumed high incidence of alloimmunisation. We have retrospectively analysed data of 79 multitransfused patients (74 adults, 5 children) with detectable warm autoantibodies and transitory or persisting haemolytic anaemia. All patients had received blood transfusions on at least two occasions. Patients were reexamined at least twice within the first 6 months of transfusion (duration of follow-up 6 months-12 years). 53 patients had received blood transfusions because of decompensated AIHA, all of whom presented with detectable autoantibodies against red blood cells. None of these patients had transfusion-related alloimmunisation or a definite increase in haemolysis, even when the transfused red cells were serologically incompatible because of free serum autoantibodies. The other 26 patients had no signs of AIHA at presentation (negative direct and indirect antiglobulin test), but received blood transfusions for anaemia due to various other causes. 23 of these 26 patients went on to develop alloantibodies as well as autoantibodies upon transfusion, and 3 patients developed autoantibodies alone. Our findings do not support the generally accepted notion that transfusion therapy should be avoided in AIHA patients. Rather, they indicate that the incidence of alloimmunisation as well as adverse haemolytic transfusion reactions are less common in AIHA patients than in other multitransfused patients.

Cold agglutinins of anti-Pr specificity in rubella embryopathy

Cold agglutinins of anti-Pr specificity were detected in two newborn infants suffering from serologically ascertained rubella embryopathy, an IgM kappa anti-Pr(a), titer 64, and an IgM lambda anti-Pr1, titer 16. The cases are rare examples of cold agglutinin production in newborns; a possible relationship between anti-Pr specificity and rubella infection is discussed.

Cold haemagglutinin disease complicating Mycoplasma pneumoniae infection in a child under cytotoxic cancer treatment

Acute cold haemagglutinin disease, most commonly associated with underlying mycoplasma infection, is rare in children. A 3-year-old girl who developed this auto-immune disease under intensive cytotoxic treatment for rhabdomyosarcoma is presented. Clinically, a livedo reticularis skin pattern upon exposure to cold which was reversible at room temperature and a spontaneous red cell agglutination of blood samples in vitro led to the diagnosis. Together with bronchopneumonia the girl developed hyper-IgM, high antibody titres against Mycoplasma pneumoniae, as well as high titres of cold agglutinins. Laboratory signs of mild intravascular haemolysis were found. Positive direct antiglobulin test resulted from coating of red cells with C3d and C4. Three different antibodies were identified in serum: nonspecific cold agglutinins without complement activation, anti-I specific cold agglutinins with complement activation, as well as a weak biphasic Donath-Landsteiner haemolysin. Under antibiotic treatment and a short course of predisolone the clinical course was mild.

Donath-Landsteiner autoimmune hemolytic anemia in children. A study of 22 cases

During the last 4 years, we have studied a total of 531 adults and 68 children with clinically and serologically well-defined forms of immune hemolytic anemias. Among these, Donath-Landsteiner (DL) hemolysis was the underlying disease in 22 of the 68 children (32.4%), but was not observed in adults. All children with DL hemolysis suffered from acute infections presumably of viral origin. In none of the cases was the DL hemolysis suspected clinically. Boys were more often affected than girls. The hemolytic episodes were severe, but resolved within few weeks. Serologically, all patients had a strongly positive direct antiglobulin test (DAT) using anti-C3d reagents, but a weak (n = 6) or negative (n = 16) IgG-DAT. DL hemolysins were always weak and transient, detectable with enzyme-treated red blood cells (RBC) in all, with untreated RBC in 12 of 22 sera. To explore the reason why these weak antibodies can cause extensive hemolysis in vivo, we compared the action of DL antibodies and of cold agglutinins (anti-I) on RBC by several reincubations at 4 and at 37 degrees C. The data obtained from this experiment demonstrate a stronger aggravation of hemolysis by DL than by anti-I antibodies, presumably due to low-affinity interaction between the cells and DL antibodies.

Erythromycin-induced immune hemolytic anemia

A 3-year-old female receiving Pediazole (erythromycin ethylsuccinate and sulfisoxazole) for tonsillitis and otitis media developed severe hemolytic anemia. No serum drug-dependent antibodies could be demonstrated with an in vitro 'immune-complex' method using Pediazole, pure erythromycin ethylsuccinate or pure sulfisoxazole. However, a method using red cells coated with erythromycin base showed in vitro lysis of the erythromycin-coated red cells. This is only the second case of immune hemolytic anemia associated with erythromycin and the first where in vitro drug-dependent hemolysis was demonstrable.

High-dose intravenous IgG therapy in a seven-week-old infant with chronic autoimmune hemolytic anemia

A 7-week-old male infant tested positive for autoimmune hemolytic anemia. Serological studies revealed a positive Coombs test and a strong antibody with relative anti-E specificity. Despite corticosteroid therapy, he frequently suffered severe hemolytic crises. During the course of the disease he had pneumonia, subcutaneous abscess, and sepsis, which were thought to be caused by his immunosuppressive state. His clinical course was chronic and refractory. Recently, high-dose intravenous IgG therapy for the treatment of chronic AIHA has been reported, but it has not been successful in the management of adult AIHA. We attempted this therapy in our patient, and successful management was obtained.

Autoimmune haemolytic anaemia in childhood associated with non-complement binding IgM autoantibodies

Red cell bound IgM autoantibodies free of associated IgG autoantibodies and unable to activate complement have not yet been considered as the cause of autoimmune haemolytic anaemia (AIHA). We report on warm type AIHA resulting from the action of IgM autoantibodies on circulating RBC. Twelve children (eight of whom were infants) with relatively severe haemolytic anaemia were studied. Whereas the clinical findings and courses of all children appeared to be compatible with warm type AIHA, the serological findings during the haemolytic phase were atypical in that the direct antiglobulin test (DAT) was negative in 11, and positive in one case due to C3d only. The use of radiolabelled antihuman globulin antibodies showed, however, that the RBC of all the patients were sensitized with warm IgM antibodies. Elevated values of IgA and/or IgG immunoglobulins on the patients' RBC were found to be present in only two cases. Complement activation by IgM autoantibodies could not be detected in all other cases neither in vivo nor in vitro. Thus, we conclude that non-complement binding IgM autoantibodies were responsible for the AIHA in the majority of these children possibly representing an as yet unrecognized variant of warm type AIHA.

Intravenous treatment of autoimmune hemolytic anemia with very high dose gammaglobulin

Autoimmune hemolytic anemia (AIHA) has been considered to be unresponsive to intravenous gammaglobulin (IVGG) at the doses that are effective in immune thrombocytopenic purpura and autoimmune neutropenia (usually 2 g/kg total dose). This study reports the use of a higher dose (5 g/kg total dose over 5 days) in four severe cases of AIHA which resulted in a sustained remission in two patients, a transient response in the third, and a failure in the forth patient. These data suggest that larger quantities of IVGG may be needed in this disease, possibly because the reticuloendothelial system appears to be enlarged in AIHA patients.