Corni Fructus-Induced Acute Interstitial Nephritis / 대한내과학회지

ABSTRACT

Drug-induced interstitial nephritis is one cause of acute kidney injury. Although traditional remedies have been widely used in South Korea, Corni fructus-induced interstitial nephritis has not been reported in the general population. A 65-year-old female patient was admitted with sudden onset of gross hematuria after ingesting Corni fructus tea for 2 weeks. Her initial lab findings showed a blood urea nitrogen level of 35.1 mg/dL, creatinine level of 1.7 mg/dL, albumin level of 4.5 g/dL, and hemoglobin level of 10.3 g/dL. Urinalysis revealed SG (1.025), blood (many), protein (+), and WBC (0-3/HPF). Her 24-hour total protein level was 1,120 mg/day. No specific abnormalities were found on serum and urine protein electrophoresis. Kidney biopsy demonstrated severe mononuclear cell infiltration into the renal interstitium with mild tubular atrophy and pericapsular fibrosis. Immediate withdrawal of Corni fructus, appropriate education, and conservative management resulted in gradual restoration of her renal function. This case implies that Corni fructus may be a causative allergen that induces acute interstitial nephritis in some patients.