Acute arterial thrombosis in acute promyelocytic leukaemia

Localized large vessel thrombosis in acute leukaemia is rare, haemorrhagic complications being more common.

We present a patient with acute promyelocytic leukaemia (APL) presenting with an acutely ischaemic lower limb. Large vessel thrombosis is a rare presentation of APL. We reviewed the literature on the coagulopathy of APL and discuss the pathology and current treatment options.

Disordered haemostasis is typical of acute promyelocytic leukaemia (FAB M3) and relates to the intrinsic properties of the blast cells as well as thrombocytopenia from bone marrow involvement. Expression of procoagulants, stimulation of cytokines and alterations in endothelial cell anticoagulant properties initiate a disseminated intravascular coagulation (DIC) resulting in the typical clinical and laboratory findings in APL. The promyelocytes are characterized by the balanced reciprocal translocation between chromosomes 15 and 17. All-trans-retinoic acid (ATRA) induces differentiation in these cells, revolutionizing the treatment of APL.

Unexpected limb ischaemia in a young, apparently healthy patient might be the presenting symptom of an underlying haematological disorder such as APL. A thorough haematological investigation should be performed prior to contemplating surgery. New treatment strategies based on knowledge of the molecular biology of APL has improved the prognosis of patients suffering from APL.