Acute interstitial nephritis due to proton pump inhibitors
A 68-year-old female was admitted with bilateral loin pain and recurrent vomiting for 1 week. She was prescribed esomeprazole for dyspepsia 3 weeks ago. She was afebrile, mildly volume depleted with a BP of 100/70 mmHg Intravenous saline was started. Serum creatinine was 2.6 mg/dl with trace proteinuria and pyuria. Renal biopsy showed AIN with dense interstitial infiltrates of lymphocytes, plasma cells, and eosinophils. Urine culture grew E. coli which was treated by antibiotics. PPI was stopped and oral prednisolone was started on 1 mg/kg dose for 8 weeks, which resulted in excellent recovery of her renal function. Her serum creatinine stabilized at 1.2 mg/dl at 4 months.