Dual mutation (MTHFR A1298C with PAI (4G) mutation) manifesting with bilateral lower limb gangrene in a neonate.

Neonates are at highest risk of thrombosis among paediatric patients. The relative prothrombotic state in a well neonate is compensated by other factors preventing spontaneous thrombosis; however, in a neonate with genetic predisposition, the balance is tilted predisposing them to a life-threatening thrombotic episode. We describe a rare case of methylenetetrahydrofolate reductase A1298C (homozygous) mutation along with plasminogen activator inhibitor (4G) mutation in a neonate who developed bilateral lower limb gangrene following thrombosis of the iliac vessels without any triggering factor. The neonate underwent thrombectomy as debulking measure along with thrombolytic therapy followed by unfractionated heparin and low-molecular-weight heparin which is still being continued along with oral aspirin. The neonate had to undergo amputation of both the involved lower limbs in view of dry gangrene. This case highlights that the dual mutations causing the prothrombotic state predispose the individual to the spontaneous life-threatening thrombotic episode as compared with the single mutation.