In:
Acta Haematologica, S. Karger AG, Vol. 140, No. 1 ( 2018), p. 10-17
Abstract:
〈 b 〉 〈 i 〉 Background: 〈 /i 〉 〈 /b 〉 Direct antiglobulin test (DAT)-negative warm autoimmune hemolytic anemia (AIHA) is mainly caused by three mechanisms: red blood cell (RBC)-bound immunoglobulin (Ig)G below the detection limit of routine DAT; RBC-bound IgA or IgM; or low-affinity autoantibodies. Although most cases of DAT-negative AIHA are thought to be caused by RBC-bound IgG, and combinatory serological analyses are recommended, the relative ratios of each mechanism have not been clarified. 〈 b 〉 〈 i 〉 Methods: 〈 /i 〉 〈 /b 〉 Two groups of patients with undiagnosed hemolytic anemia and negative conventional tube method-DAT (TM-DAT) were investigated using anti-IgA and anti-IgM sera, or column agglutination method-DAT (CM-DAT), respectively, in addition to radioimmunological quantitation of RBC-bound IgG. 〈 b 〉 〈 i 〉 Results: 〈 /i 〉 〈 /b 〉 Three of 73 patients with DAT-negative AIHA showed positive RBC-bound IgA and normal amounts of RBC-bound IgG. Another group of 3 patients were RBC-bound IgM-positive, but only one of these showed normal amounts of RBC-bound IgG. In another group of patients with DAT-negative AIHA, 4 of the 20 showed positive CM-DAT and negative CM-DAT after washing RBCs. Three of these patients had normal amounts of RBC-bound IgG. Five patients with positive CM-DAT both before and after washing RBCs had high amounts of RBC-bound IgG. 〈 b 〉 〈 i 〉 Conclusion: 〈 /i 〉 〈 /b 〉 Relative ratios of patients with DAT-negative AIHA resulting from RBC-bound IgG, RBC-bound IgA, RBC-bound IgM, and low-affinity IgG were estimated as 80, 4, 1 and 15%, respectively. A new classification and diagnostic algorithm for DAT-negative AIHA were proposed.
Type of Medium:
Online Resource
ISSN:
0001-5792
,
1421-9662
Language:
English
Publisher:
S. Karger AG
Publication Date:
2018
detail.hit.zdb_id:
1481888-7
detail.hit.zdb_id:
80008-9
