[Correlations between crystalluria and composition of calculi].
The successful fragmentation of kidney stones by means of extracorporeal shock wave lithotripsy partly depends on stone composition. In case of incomplete or coarse fragmentation, multiple urological procedures following ESWL may be necessary for removal of obstructive fragments. It is difficult to be sure that a given stone will be successfully destroyed. X-ray examinations before treatment are useful to classify calculi as calcium stones or not. Nevertheless, such investigations are often not sufficient to identify the main crystalline phases which form the stone and that can make it either resistant or friable to ESWL.


OBJECTIVE
The aim of this study was to compare crystalluria and stone composition in patients with kidney calculi.


METHODS
Seventy-five untreated patients (54 males, 21 females) were included. Their first morning urine was collected three days before surgical removal of the stone. Urine samples were kept at 4 degrees C during 48 hours before examination.


RESULTS
Crystalluria occurred in 97.3% of urine specimens. Weddellite was the most frequent crystalline species found in urine (66.2%), followed by carbapatite (33.1%) and whewellite (23.1%). When compared to stone composition, crystalluria was mainly made of weddellite in urines from 68% of patients with weddellite-rich calculi. Stones from patients presenting with whewellite crystals in urine were mainly composed of whewellite in 88.9% of cases. Struvite stones were associated with struvite and carbapatite crystalluria in 85.7% of cases.


CONCLUSIONS
Crystalluria studies could be of clinical interest to predict the main crystalline phase of calcium-containing stones in order to define the best procedures for stone removal.
Kaid-Omar
Z
Z
Institut de Chimie Industrielle, Centre Universitaire, Mostaganem, Algérie.
Daudon
M
M
Attar
A
A
Semmoud
A
A
Lacour
B
B
Addou
A
A
D000328:Adult; D002129:Calcium Oxalate / Q000032:analysis / Q000652:urine*; D002130:Calcium Phosphates / Q000032:analysis / Q000652:urine; D003460:Crystallization; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000737:chemistry* / Q000601:surgery / Q000652:urine*; D017616:Magnesium Compounds / Q000032:analysis / Q000652:urine; D008297:Male; D008859:Microscopy, Polarization; D008875:Middle Aged; D010710:Phosphates / Q000032:analysis / Q000652:urine; D013055:Spectrophotometry, Infrared; D000069877:Struvite; D014527:Uric Acid / Q000032:analysis / Q000652:urine
D002130:Calcium Phosphates; D017616:Magnesium Compounds; D010710:Phosphates; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; D002129:Calcium Oxalate; D014527:Uric Acid; C485838:calcium phosphate, monobasic, anhydrous; C016188:weddellite; C020243:calcium phosphate; D000069877:Struvite; C485829:calcium phosphate, dibasic, anhydrous