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.

Brown recluse spider (Loxosceles reclusa) envenomation leading to acute hemolytic anemia in six adolescents.

Loxosceles reclusa (brown recluse spider) bites often cause local envenomation reactions; however, acute hemolysis from systemic loxoscelism is rare. To highlight this important diagnostic consideration for unexplained hemolysis in areas endemic for brown recluse spiders, we report on 6 adolescents with acute hemolytic anemia from presumed L reclusa bites.

A novel G6PD mutation leading to chronic hemolytic anemia.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an important cause of hemolytic anemia worldwide. Severely affected patients have chronic hemolysis with exacerbations following oxidative stress. Mutations causing severe chronic non-spherocytic hemolytic anemia (CNSHA) commonly cluster in Exon 10, a region important for protein dimerization. An African-American male presented at age 2 weeks with pallor and jaundice, and was found to have hemolytic anemia with G6PD deficiency. His severe clinical course was inconsistent with the expected G6PD A(-) variant. DNA sequencing revealed two common mutations (A(-)) and a third novel Exon 10 mutation. This inherited haplotype represents a novel triple G6PD coding mutation causing chronic hemolysis.