Paroxysmal cold haemoglobinuria coexisting with cold agglutinins in a patient with syphilis resulting in peripheral gangrene: a case report.

Cold-reactive antibodies may cause peripheral ischaemia, occasionally proceeding to gangrene on exposure to cold. A 46-year-old male with syphilis, presented with an unusual combination of both paroxysmal cold haemoglobinuria and cold agglutinin disease, resulting in peripheral gangrene and requiring bilateral below knee amputations.