Beyond Ingestion: Nasal Inhalation-Induced Aristolochic Acid Nephropathy from a Traditional Herbal Remedy - A Case Report.

Introduction: Aristolochic acid nephropathy (AAN), a progressive form of interstitial nephritis, is predominantly associated with the oral ingestion of herbal remedies containing aristolochic acid (AA).

Case presentation: This report details a rare case of AAN linked to nasal inhalation of a traditional herbal preparation. An 80-year-old monk with chronic kidney disease and rapidly declining kidney function underwent kidney biopsy, revealing severe interstitial fibrosis, tubular atrophy, and the presence of aristolochic acid-DNA adducts, confirming the diagnosis. Further investigation uncovered prolonged use of a nasal inhalation remedy for alertness and nasal decongestion. Analysis of the preparation using liquid chromatography-diode array detection-quadrupole time-of-flight mass spectrometry identified aristolochic acid I, directly linking the remedy to the renal pathology.

Conclusion: This case highlights a previously underrecognized route of AA exposure and underscores the critical importance of comprehensive history-taking, increased regulation of alternative medicines, and public awareness to prevent similar cases of nephrotoxicity.