BACKGROUND Incidental findings of renal infarct secondary to thrombosis in acutely ill patients present a unique challenge in diagnosis. We present a case of idiopathic renal infarct to highlight its workup and management and encourage further investigation of renal infarctions. CASE REPORT A 68-year-old woman with a past medical history of diet-controlled diabetes, hypertension, and hyperlipidemia presented to the Emergency Department (ED) for abdominal pain. She was found to be in diabetic ketoacidosis with pyelonephritis, so she was admitted to the Intensive Care Unit (ICU) for insulin and dextrose drip. Due to her abdominal pain, she underwent computed tomography (CT) of her abdomen and pelvis with contrast. This revealed multifocal infarcts of her right kidney with noncalcified thrombus at the proximal right renal artery. Subsequent CT angiography confirmed a right renal artery thrombus. She was started on subcutaneous enoxaparin and downgraded to basic level of care. Her history was negative for prior thrombosis, hypercoagulable state, and abdominal trauma. Echocardiogram and limited hypercoagulable workup were largely unremarkable. A multidisciplinary team evaluated the patient and recommended no surgical intervention. Following downgrade from the ICU, the patient was transitioned from enoxaparin to apixaban. She was discharged with plans for anticoagulation for 6 months, aspirin daily, and repeat CT angiogram abdomen/pelvis in 1 month. CONCLUSIONS This case illustrates the difficulties in elucidating the cause of incidental renal thrombosis in an acutely ill patient. Diagnostic workup is limited in the inpatient setting, but therapeutic anticoagulation remains the standard of treatment regardless of etiology.