Why does calcium oxalate precipitate to form kidney stones when oxalate concentration exceeds a saturation threshold in the nephron?

💡 Explanation

Kidney stones form when the supersaturation of calcium and oxalate overcomes the protective effect of crystallization inhibitors. Reduced glycosaminoglycans (GAGs) lessen the inhibition of crystal growth, because these molecules normally bind to calcium oxalate crystals and prevent their aggregation. Therefore, reduced GAGs levels lead to increased stone formation, rather than preventing it, as other mechanisms might suggest.

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