Postkidney Transplant May-Thurner Syndrome Causing Ipsilateral Left Lower-Extremity Edema and Left Lower-Quadrant Kidney Allograft Dysfunction

Introduction: May-Thurner syndrome (MTS) results from extrinsic venous compression of the iliocaval veins. We report progressive MTS post-DDK with ipsilateral left LE edema and DDK dysfunction. Case Description: A 43-yo male with ESRD from ADPKD, on hemodialysis for 7 years received a DDK in 2024. 9 weeks later, he developed unilateral painless left LE swelling (Figure 1). Dopplers ruled out LE DVT but showed extrinsic 75%-90% narrowing of the left external iliac vein from compression by the large left ADPKD kidney and the left LQ DDK, consistent with MTS (Figure 2). DDK ultrasound and Duplex showed no hydronephrosis, and no renal artery stenosis. Serum creatinine that had promptly progressively declined to 1.60 mg/dL has since partially reversed this trend. An open left nephrectomy is planned. Discussion: Our patient has May-Thurner syndrome with symptomatic ipsilateral LE edema and further complicated by new evidence of renal allograft dysfunction. To avoid further renal allograft compromise and to mitigate the lower extremity swelling, the patient will undergo an urgent open native left nephrectomy.New left LE swelling 9 weeks post-DDKLarge ADPKD kidneys on prior CT