Post-extracorporeal Membrane Oxygenation (ECMO) Bilateral Urolithiasis in an Adolescent With B-cell Acute Lymphoblastic Leukemia (ALL): A Case Report

Acute kidney injury and metabolic derangements are common after extracorporeal membrane oxygenation (ECMO), yet their potential contribution to urinary stone formation is rarely described. Critically ill patients may develop lithogenic conditions related to tubular injury, oliguria, prolonged immobilization, catabolism, infection, and alterations in urinary solute handling. We report the case of a 13-year-old girl with B-cell acute lymphoblastic leukemia undergoing induction chemotherapy who developed Pseudomonas septic shock requiring prolonged extracorporeal support with venoarterial ECMO followed by venovenous ECMO. Her course was further complicated by acute respiratory distress syndrome, bilateral pneumothoraces, and prolonged intensive care unit hospitalization. During recovery, computed tomography revealed bilateral renal and ureteral calculi with moderate left hydroureteronephrosis. Despite significant stone burden, the patient remained clinically stable without urinary tract infection, preserved renal function, and gradual radiographic improvement. Because of ongoing chemotherapy, immunosuppression, pulmonary risk, and fluctuating procedural candidacy, management required repeated multidisciplinary reassessment involving pediatric urology, oncology, pulmonology, nephrology, and the patient’s family. Initial decompression and staged ureteroscopic intervention were considered; however, serial imaging demonstrated partial spontaneous migration of calculi, allowing temporary conservative management with tamsulosin and close surveillance. Persistent left-sided impaction and limited further migration ultimately supported definitive bilateral ureteroscopy with laser lithotripsy and short-term stenting once medically optimized. This case highlights the complex balance between surgical urgency and systemic risk in post-ECMO patients with urolithiasis. It also raises the possibility that ECMO-related renal injury and critical illness physiology may contribute to the formation of low-density or matrix-type stones. Individualized multidisciplinary decision-making is essential in medically fragile patients.