Characterization of direct antiglobulin test-negative autoimmune hemolytic anemia: a study of 154 cases.

Abstract

Direct antiglobulin test (DAT)-negative (DAT-)autoimmune hemolytic anemia (AIHA) is empirically thought to show the same clinical conditions as DAT-positive (DAT+)AIHA, with the exception of an adequate amount of red blood cell (RBC)-bound immunoglobulin (Ig)G. We investigated the clinical characteristics of DAT-AIHA in comparison with DAT+AIHA. Of the 582 patients referred to our laboratory with undiagnosed hemolytic anemia, AIHA was clinically diagnosed in 216 patients (DAT-AIHA, n = 154; DAT+AIHA, n = 62). The percentage of reticulocytes, mean corpuscular volume, RBC-IgG levels, white blood cell count, and total protein (TP) levels were significantly higher in patients with DAT+AIHA than patients with DAT-AIHA. The hemoglobin level was significantly lower in patients with DAT+AIHA. No significant differences between patients with DAT-AIHA and DAT+AIHA existed with respect to age, gender, idiopathic/secondary nature, complications such as Evans syndrome, effectiveness of steroid treatment, or survival rate at 1 year following diagnosis. Patients with DAT-AIHA required significantly lower doses of steroids for maintenance therapy. Based on multivariate analysis of idiopathic DAT-AIHA (n = 110), TP and Evans syndrome were associated with the effectiveness of steroids (adjusted odds ratio [aOR], 1.36/[0.1 g/dl]; 95% confidence interval [CI], 1.01-1.84) and survival at the 1-year follow-up (aOR, 0.1; 95% CI, 0.01-0.88). Our results indicate that patients with DAT-AIHA generally suffer milder anemia and hemolysis than patients with DAT+AIHA, respond equally well to steroids, and have comparable survival at 1-year.

• Authors: Toyomi Kamesaki, Tomonori Toyotsuji, Eiji Kajii
• Journal: American journal of hematology (Am J Hematol) Vol. 88 Issue 2 Pg. 93-6 (Feb 2013) ISSN: 1096-8652 [Electronic] United States
• PMID: 23169533 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2012 Wiley Periodicals, Inc.

Chemical References

• Blood Proteins
• Immunoglobulin G
• Steroids

Topics

• Adult
• Aged
• Anemia, Hemolytic, Autoimmune (blood, drug therapy, immunology, physiopathology)
• Blood Proteins (analysis)
• Case-Control Studies
• Coombs Test
• Erythrocyte Indices
• Erythrocytes (metabolism)
• Female
• Follow-Up Studies
• Hemolysis
• Humans
• Immunoglobulin G (analysis, metabolism)
• Maintenance Chemotherapy
• Male
• Middle Aged
• Reticulocyte Count
• Severity of Illness Index
• Steroids (administration & dosage, therapeutic use)
• Survival Analysis