Constituents of urinary calculi containing struvite.

In a collection of 615 stones containing struvite and in which the sequential deposition of the constituents from the nucleus to the surface had been determined, other substances were found to follow a marked deposition of struvite in 139 cases. In 122, the compound was accompanied by struvite, in 16, struvite was replaced by it and in 1, both types of deposition had occurred in different layers. All urinary stone constituents could accompany struvite and many could replace this compound.