Warm-reactive Autoantibodies in Pediatric Patients

Abstract

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.

Diagnostic and therapeutic challenges of primary autoimmune haemolytic anaemia in children

“…In this situation, alloantibodies are very rare and acute transfusion reactions are uncommon, because the transfused RBCs and the patient’s own RBCs have the same survival in the presence of the autoantibody 38. On the contrary, if the child has previously undergone transfusion, the coexistence of alloantibodies and autoantibodies is common 39. In these patients, the alloantibody is very often shadowed by the panagglutinin, and therefore may produce a delayed haemolytic reaction that would worsen the anaemia 40–42.…”

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

“…[2][3][4][5][6] Recent literature contains information from small series, mainly based on laboratory tests, and involving very few centers. [7][8][9][10] The prevalence of AIHA in childhood is still unknown, but likely increases with age, as for most autoimmune disorders. Evans' syndrome (ES) was first described as hemolytic anemia with a positive direct antiglobulin test (DAT) and immune thrombocytopenia occurring simultaneously or in succession, in the absence of any known etiology.…”

Autoimmune Hemolytic Anemia and Red Blood Cell Autoantibodies

“…3 Several other laboratory findings can be useful in determining the presence of hemolysis. For example, peripheral tests and complete blood cell counts typically reveal a normochromic, normocytic anemia; polychromasia; and reticulocytosis.…”

“…2 Although RBC autoantibodies are seen in patients of all ages, a general increase in incidence is observed with age, most dramatically in patients older than 50 years. 3 The RBC autoantibodies are generally classified as either warm RBC autoantibodies, if optimum reactivity with RBCs occurs at 378C, or cold RBC autoantibodies, if optimum reactivity with RBCs occurs at less than 308C.…”