title: An experimental study on residual lithiasis after shock wave lithotripsy.
abstract: The main objective of this paper was to study residual lithiasis after extracorporeal shock wave lithotripsy (post-ESWL), with the aim of contributing to the development of effective prophylactic measures. In vivo regrown calcium oxalate monohydrate (COM) post-ESWL residual fragments were studied by stereoscopic microscopy, infrared spectroscopy and scanning electron microscopy with an energy dispersive X-ray analyzer. An in vitro system was also used to study the regrowth of post-ESWL fragments of COM calculi. The regrowth was evaluated as the relative increase in the weight of the fragments. The effects of a calcium oxalate crystallization inhibitor (phytate) were also evaluated. All of the in vivo regrown COM real residual post-ESWL fragments exhibited practically the same internal structural features. The in vitro studies demonstrated that the regrowth of post-ESWL residual fragments, in the absence of crystallization inhibitors, occurred even using normocalciuric/normooxaluric urine and could be detected at 24 h. At 144-240 h, the formation of new COM columnar zones was observed. The presence of 1.5 mg/l of phytate totally blocked the growth process. When hypercalciuric/normooxaluric urine was used, significant amounts of disorganized calcium oxalate dihydrate (COD) crystals were formed. The in vitro regrowth of post-ESWL COM fragments was clearly influenced by the presence of crystallization inhibitors. These data also demonstrate the importance that effective prophylactic therapies could exert on preventing recurrence.
authors.affiliation: Laboratory of Renal Lithiasis Research, Institute of Health Sciences Research (IUNICS), University of Balearic Islands. 07122 Palma of Mallorca, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Costa-Bauzá
authors.forename: J
authors.initials: J
authors.lastname: Perelló
authors.forename: B
authors.initials: B
authors.lastname: Isern
authors.forename: F
authors.initials: F
authors.lastname: Grases
mesh_terms: D002129:Calcium Oxalate / Q000737:chemistry; D003460:Crystallization / Q000295:instrumentation; D003461:Crystallography; D006801:Humans; D066298:In Vitro Techniques; D007669:Kidney Calculi / Q000473:pathology* / Q000628:therapy*; D008096:Lithotripsy; D008855:Microscopy, Electron, Scanning; D010833:Phytic Acid / Q000494:pharmacology; D014556:Urine / Q000737:chemistry
chemical_list: D002129:Calcium Oxalate; D010833:Phytic Acid