A case of recurrent paroxysmal cold hemoglobinuria with the different temperature thresholds of Donath-Landsteiner antibodies.

In this article, we first report a case of recurrent paroxysmal cold hemoglobinuria with serologic confirmation. On 2 occasions, the Donath-Landsteiner (DL) antibodies belonged to an IgM subclass and showed neither anti-P nor anti-I specificity. Furthermore, it is very interesting that the temperature thresholds of DL antibodies were different on each occasion. Although acute paroxysmal cold hemoglobinuria is considered to be self-limited and transient, we should be careful of its possible recurrence. DL tests must be repeated after the complete recovery from the first episode, with careful attention to several possible causes of false-negative DL tests.