[Composition analyses of bilateral urinary tract calculis]

To explore the composition of bilateral urinary tract calculi so as to guide treatments.

A total of 126 patients with bilateral urinary calculi were recruited to undergo percutaneous nephrolithotomy or ureteroscopes lithotripsy. And 256 extracted stones were analyzed by infrared spectrophotometry.

The components of these stones were mainly mixture. The compositions included calcium oxalate (n = 214, 85%), carbonate apatite (n = 113, 45%), phosphate (n = 43, 17%) and uric acid (n = 28, 11%). And 63 patients had the same stone composition in bilateral urinary stones and 26 of them were of pure calcium oxalate, 2 phosphate while another 36 mixture. Different compositions were present in 60 patients with bilateral urinary stones.

The compositions of bilateral urinary stones are not always identical in a patient. The overall patient status should be considered if one side urinary stone is treated according to the composition analysis results of another side counterpart.