Patient: Female, 43-year-old Final Diagnosis: Perinephric hematoma Symptoms: Chills • fever • flank pain Medication: — Clinical Procedure: — Specialty: General and Internal Medicine Objective: Rare co-existance of disease or pathology Background: Perinephric hematomas are rare, especially following ureteral stent placement. Etiologies of perinephric hematomas include post-extracorporeal shockwave lithotripsy, Wunderlich syndrome, and renal cell carcinoma, none of which occurred in our patient, who underwent stent replacement. Subcapsular renal hematoma, rather than a perinephric hematoma, can occur following double-J ureteral stent placement. Also, renal parenchymal perforation leading to perinephric hematoma development are complications of double-J ureteral stent placement. Herein, we present a case of a perinephric hematoma following a double-J ureteral stent placement for a ureteral obstruction causing hydronephrosis. Case Report: A 43-year-old woman with type 2 diabetes mellitus, hypertension, systemic lupus erythematosus, and recurrent nephrolithiasis presented to our hospital with left flank pain of a 1-day duration. The patient was found to have an obstructive kidney stone causing hydronephrosis. She underwent stent placement and then developed a perinephric hematoma days later. Typically, hematomas are treated conservatively and have spontaneous resolution. The patient received 2 weeks of intravenous antibiotics and 2 more weeks of oral antibiotics, and failed conservative treatment. She re-presented to our hospital 3 days after discharge. Upon the second admission, a perinephric drain was placed. The patient was given another course of antibiotics and was discharged 18 days later. Conclusions: A perinephric hematoma is a rare complication after ureteral stent placement. Perinephric hematoma development can be decreased by controlling blood pressure, treating preoperative urinary tract infections, and shortening operating time during ureteroscopy. It is important to reevaluate potential causes of continued abdominal pain with laboratory testing and repeat imaging.