Diagnostic Considerations
Donath-Landsteiner hemolytic anemia (DLHA) may be difficult to diagnose. It can be confused with cold agglutinin disease, with mixed type autoimmune hemolytic anemia and with warm-antibody autoimmune hemolytic anemia. [20]
In general, cold agglutinin disease is characterized by the presence of very high cold agglutinin titers and the absence of hemoglobinuria, while warm-antibody autoimmune hemolytic anemia is typically diagnosed by positive results on the anti-IgG direct antiglobulin test.
Donath-Landsteiner (D-L) autoantibody is present only in DLHA and is therefore specific. The sensitivity of this test, however, is low. Many patients with the condition are undiagnosed. The D-L test is often negative in patients who have the condition if the antibody titer is low.
A number of more sensitive assays exist. The use of RBCs from patients with paroxysmal nocturnal hemoglobinuria (PNH) increases the sensitivity of the standard D-L test because PNH RBCc are more sensitive to the lysing ability of complement. This modification increases the ability to detect patients with the condition. The most sensitive diagnostic assay for DLHA uses radiolabeled antibody. [25]
Go to Pediatric Chronic Anemia, Anemia of Prematurity, Fanconi Anemia, Pediatric Acute Anemia, and Pediatric Megaloblastic Anemia for complete information on these topics.
Differential Diagnoses
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Blood smear showing spherocytosis, polychromatophilia, and erythrophagocytosis by neutrophils.
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Blood smear showing spherocytosis, polychromatophilia, and erythrophagocytosis by neutrophils.
