A Rare Case of Atypical Haemolytic Syndrome Following Right Retrograde Intrarenal Surgery (RIRS)

: Renal failure, non-immune hemolytic anemia, and thrombocytopenia are the hallmarks of the uncommon but potentially fatal complement system-related illness known as atypical hemolytic uraemic syndrome (aHUS). We describe the case of a 46-year-old woman who underwent right retrograde intrarenal surgery (RIRS) for a 1.5 cm urinary stone in the renal pelvis and experienced septic shock on postoperative day 1 caused by aHUS. The patient received continuous venovenous hemodiafiltration (CVVHDF) for six days, eculizumab, a monoclonal antibody that blocks terminal complement activation, and three plasma exchanges with fresh frozen plasma, resulting in a progressive normalization of hemolytic parameters. Two months after the RIRS, the patient underwent percutaneous nephrolithotripsy to remove residual kidney stones. Three days before the surgery, she received a dose of eculizumab. The procedure went smoothly, and there were no postoperative complications. To the best of our knowledge, this is the report that mentions aHUS as a postoperative complication following endourology procedures. This report focuses on multidisciplinary diagnosis, treatment, and follow-up strategies for this unique complication in urology.