This case report describes a 71-year-old female with multiple comorbidities who presented with symptoms suggestive of stroke and was subsequently found to have severe acute kidney injury (AKI) due to acute interstitial nephritis (AIN). The patient has normal kidney function at baseline. She has been on hydrochlorothiazide and metoprolol succinate for hypertension for several years. Due to severe acute kidney injury, a kidney biopsy was performed, revealing severe Acute Interstitial Nephritis secondary and multiple intratubular oxalate crystals. The patient's renal function improved after withdrawing HCTZ, volume repletion and initiating prolonged prednisone taper. We attempt to provide some insights through our paper into the mechanism of acute renal failure from crystal nephropathy and its management.