Not Just Another Deep Vein Thrombosis: Unmasking May-Thurner Syndrome.

May-Thurner syndrome (MTS) is a condition characterised by the compression of the left iliac vein by the right common iliac artery, leading to venous stasis and an increased risk of deep vein thrombosis (DVT). This case report discusses a 56-year-old woman presenting with progressive swelling and pain in her left leg. Imaging studies revealed a significant left iliofemoral deep vein thrombosis and venous collateralization, leading to a diagnosis of May-Thurner syndrome. Despite the elevated levels of D-dimer and inflammatory markers in circulation, the thrombophilia screening revealed that she carried a heterozygous prothrombin 20210A allele, which contributes to her vulnerability to thrombotic events. The utilisation of Doppler ultrasound and CT venography was essential to validate the diagnosis, which is often challenging due to the nonspecific nature of the signs. The patient received anticoagulation therapy as part of a conservative treatment approach, which included careful monitoring and collaboration with various other specialties. This case underscores the importance of prompt identification of MTS of the left leg in patients presenting with leg swelling, pain, or deep vein thrombosis, especially in high-risk individuals, including those who have undergone surgery or have a familial predisposition. The primary focus of management involves anticoagulation, preventing recurrence, and effectively addressing complications.