[Analysis and clinical implication of upper urinary tract stone's bacterial spectrum]

To analyze the pathogenic bacterial's distribution and the drug resistance in the upper urinary tract stones, and to provide the information for choosing suitable antibiotics.

Stone samples were taken for culture and for drug sensitivity test in 146 patients undergoing percutaneous nephrolithotomy between April 2007 and October 2008, and the results were analyzed.

Pathogens presented in 72 (49.3%) patients. There were 70 (86.4%) Gram-negative bacteria strains. Escherichia coli, Pseudomonas aeruginosa and Enterobacter cloacae were the predominant bacteria, accounted for 30.9%(25 strains), 23.5% (19 strains) and 12.3% (10 strains), respectively. There were 10 (12.3%) Gram-positive bacteria strains, the predominant bacteria was Staphylococcus epidermidis (6 strains), accounting for 7.4%. And there was 1 fungi strain (1.2%). Resistance to ampicillin/sulbactam (88.7%), ceftriaxone (81.3%) and ciprofloxacin (67.5%) was most commonly found in pathogen, and the rate of resistance to amikacin, imipenem and piperacillin/tazobactam were 8.6%, 10.0%, 10.0%, respectively. Erythromycylamine, teicoplanin, SMZ-TMP, nitrofurantoin were sensitive to Gram-positive bacteria.

Bacterial's distribution of upper urinary tract stones are multiple, and the majority pathogen is Gram-negative bacteria. A big variant resistance is found among different bacterium. The suitable antibiotics should be chosen according to the different bacterium in the patients who underwent percutaneous nephrolithotomy.