title: Study of calcium phosphate crystalluria.
abstract: When the frequency of heavy calcium phosphate crystalluria was compared among postprandial urine specimens collected from 152 healthy persons (group 1) and 108 patients with calcium urolithiasis (group 2), there was no significant difference between these groups. However, the frequency of crystalluria was significantly greater in 49 patients in group 2 who required or had required surgical intervention for calcium stone disease than in group 1 (p less than 0.05). Calcium phosphate precipitates collected from 7 urine specimens by repeated centrifugation were studied by infrared, X-ray, thermal and electron probe analyses. The principal component of the precipitates was poorly crystallized apatite associated with some organic material. The precipitates from the 7 samples appeared as aggregates of fine spherules less than 1 micron. in diameter, and the calcium-to-phosphate molar ratio of a spherule ranged from 1.02 to 1.19. We conclude that not only calcium oxalate crystalluria but calcium phosphate crystalluria may have an important role in the formation of urinary stones.
mesh_terms: D000328:Adult; D002129:Calcium Oxalate / Q000652:urine; D002130:Calcium Phosphates / Q000652:urine*; D004577:Electron Probe Microanalysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013055:Spectrophotometry, Infrared; D014545:Urinary Calculi / Q000032:analysis / Q000652:urine*; D014961:X-Ray Diffraction
chemical_list: D002130:Calcium Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D002129:Calcium Oxalate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; C485829:calcium phosphate, dibasic, anhydrous