Strength of Direct Antiglobulin Test as an Indicator of Disease Severity in Autoimmune Hemolytic Anemia

ABSTRACT Autoimmune hemolytic anemia (AIHA) is a rare disorder for which epidemiological studies are limited. Proper diagnosis of AIHA is supported by clinical laboratory data that demonstrate all aspects of the disease including evidence of anemia by low hemoglobin (Hb), indication of hemolysis by elevated lactate dehydrogenase, and demonstrating involvement of the immune system by a positive direct antiglobulin test (DAT). The purpose of this study was to investigate the incidence of AIHA at our institution and establish a correlation between DAT strength of reaction and AIHA disease severity. Here, we identified that AIHA is more prevalent among children and patients ages 61 to 70 years old that are female and Caucasian/White Hispanic. A positive correlation between DAT strength and disease severity was observed, and a negative correlation between DAT strength of reaction and Hb was identified. Our findings also showed a positive correlation between age and AIHA type that is dependent on DAT strength. The results from this study propose the further evaluation of DAT as a laboratory value that can indicate severity of the disease and possibly implementing a flag value for DAT when communicating results to clinicians.