Acute kidney injury following household pyrethroid aerosol insecticide exposure: a case report and literature review.

Background: Pyrethroids (PYRs) are increasingly detected in both environmental matrices and human populations. Emerging evidence underscores their potential for systemic toxicity. Biopsy-confirmed nephrotoxicity in humans remains sparsely documented, particularly in non-occupational exposure. We present a case of acute kidney injury (AKI) associated with household pyrethroid-containing aerosol insecticide exposure. Case presentation: A 55-year-old previously healthy male presented with nausea and abdominal pain and was found to have AKI on laboratory evaluation. He denied prior medication use or history of drug allergies. Detailed history revealed that the patient had stayed overnight in a small, poorly ventilated bedroom that had been heavily sprayed with a household pyrethroid-containing aerosol insecticide earlier that evening. Despite receiving empirical treatment, the patient's renal function progressively deteriorated. Kidney biopsy revealed acute tubular necrosis (ATN) together with acute interstitial nephritis (AIN). After corticosteroid therapy, his renal function partially improved within 3 weeks. During follow-up, renal function stabilized at stage 3 chronic kidney disease (CKD). Conclusion: The case suggests that inappropriate exposure to PYRs may be associated with clinically significant nephrotoxicity, a complication rarely described in humans. Clinicians should consider this environmental toxicant in the differential diagnosis of otherwise unexplained AKI. In addition, the literature review provides mechanistic insights into PYR-associated nephrotoxicity, particularly oxidative stress, inflammation, mitochondrial dysfunction, and tubular injury.