Oxalic Acid: Absorption, Excretion, and Metabolism

Abstract

The incidence of renal stone disease in this country is estimated to be approximately 0.1% of the population. Thus, nephrolithiasis represents one of the most common renal disorders in the United States. It has been documented in a number of previous studies that approximately two thirds of stones collected from patients with nephrolithiasis are composed of calcium oxalate, usually in the monohydrate form, and sometimes mixed with calcium phosphate in the form of apatite. Thus, an understanding of this particular crystalline compound is of importance in defining the pathogenesis of calcium oxalate nephrolithiasis. This discussion will focus on oxalic acid, its physicochemical characteristics, and some of the disorders associated with excess oxalate excretion.