Inhibition of calcium oxalate crystallisation by pentosan polysulphate in control subjects and stone formers.

In vitro studies showed that sodium pentosan polysulphate (SPP) is an active inhibitor of calcium oxalate (CaOx) crystal growth and agglomeration and that it acts by increasing the negative zeta potential on the surface of CaOx crystals. Oral administration of SPP to control subjects, recurrent stone formers and patients with primary hyperoxaluria resulted in an overall increase of 8% (P less than 0.01) in the polyanionic inhibition of CaOx crystallisation in urine as measured by the zeta potential. SPP could provide a novel approach to the medical prevention of recurrent CaOx stone disease.