Glyoxylic Acid Induces Crystalline Nephropathy and Hair-Straightening Products: A Case Report

This case report highlights a 27-year-old woman who developed acute kidney injury (AKI) after using a hair-straightening product containing glyoxylic acid. The patient experienced symptoms such as asthenia, nausea, and lumbar pain, with laboratory tests indicating severe AKI. A renal biopsy revealed interstitial edema and calcium oxalate crystals, while a scalp biopsy showed epidermal necrosis. The findings suggest that glyoxylic acid is absorbed through the skin, metabolized into oxalate, and causes calcium oxalate crystallization, leading to nephropathy. Similar cases have been reported in Switzerland and France, and experimental models support this mechanism. The study calls for regulatory review and public health intervention to address the risks associated with glyoxylic acid in hair products. Early recognition and discontinuation of exposure are crucial to prevent irreversible kidney damage.