URINARY GLYCOSAMINOGLYCAN EXCRETION IN HEALTHY AND STONE-FORMING CHILDREN

Both in vivo and in vitro studies suggest that macromolecules excreted in the urine, e.g. glycosaminoglycans (GAGs) may be inhibitors of kid ney stone formation. We evaluated urinary GAG excretion in 22 children with calcium oxalate stones [8 with absorptive hypercalciuria, 6 with renal hypercalciuria (RH), 8 with normocalciuria], and in 20 age-matc hed controls. There was no significant difference between the two grou ps in the total urinary GAG level. In terms of the various GAG fractio ns, patients with RH excreted considerably less keratan sulphate and c onsiderably more dermatan sulphate than the other patients and healthy controls. There was no difference between the two groups in condroiti n sulphate, heparan sulphate and hyaluronic acid excretion. We conclud e that there is no significant correlation between the formation of ca lcium oxalate stones and urinary GAG excretion.