A contribution to the formation mechanism of calcium oxalate urinary calculi. III. On the role of magnesium in the formation of oxalate calculi.

The influence of magnesium in vitro on the precipitation of calcium oxalate was investigated. Even at maximum physiological magnesium concentrations a litholytic effect could not be observed, but the retardation of the calcium oxalate crystallization caused by magnesium might be decisive for a reduction in calculi formation. The enlargement of the calcium oxalate crystals and aggregates caused by the retardation of crystallization, however, should be regarded as a contraindicating factor for Mg therapy in oxalate calculous disease. It is safe to say that high magnesium concentrations prevent the conversion into Whewellite of the calcium oxalate calculi substance primarily formed as Weddellite.