struvite and Streptococcal-Infections

To examine urine and stone bacteriology of struvite stone formers in a large cohort of patients undergoing percutaneous nephrolithotomy (PCNL).. A total of 1191 patients, with stone and urine cultures, treated with PCNL for renal calculi were included in the study. Statistical differences were assessed using Mann-Whitney U and T-tests.. Stone cultures were positive in 72% of patients with struvite stones. Urea-splitting organisms accounted for only half of the positive stone cultures. Enterococcus (9/50, 18%), Proteus (9/50, 18%), and Escherichia coli (6/50, 12%) were the most commonly identified organisms. Notably, two-thirds of struvite formers with negative stone culture had at least one positive culture for a urea-splitting organism on urine culture going back 1 year from the time of surgery. A majority (67%) of struvite stone cultures were found to be resistant to first- and second-generation cephalosporins.. The bacteriology of struvite stones has shifted away from traditional urea-splitting organisms and antibiotic coverage must be expanded to include organisms such as Enterococcus that do not respond to cephalosporins. Causative organisms may be found by going back in time to identify the initial organism that could have induced struvite stone formation to inform preventative therapy.

Topics: Adult; Enterococcus; Escherichia coli; Escherichia coli Infections; Female; Humans; Kidney Calculi; Male; Middle Aged; Nephrolithotomy, Percutaneous; Proteus; Proteus Infections; Sepsis; Streptococcal Infections; Struvite; Tertiary Care Centers; Urea; Urinalysis

The pre-operative urine, pelvic urine, removed calculi and calculus washings were examined bacteriologically in 24 patients undergoing removal of intrarenal calculi. Four of seven patients with struvite calculi had an infected pre-operative midstream urine specimen and six of the seven removed calculi demonstrated significant bacterial growth. Proteus mirabilis was the commonest organism isolated. Of 17 patients with oxalate calculi only one had an infected pre-operative urine culture, but in four cases the removed stones were infected. Quantitative bacteriological culture of the stones and their washings demonstrated that infection is within the stone itself. Pre-operative urine culture failed to predict infection within the stone in 60% of patients with infected stones. The results suggest that the presence of infected urine together with the presence of renal calculus is indication for removal of the calculus.

Topics: Adult; Aged; Bacteriuria; Enterobacteriaceae Infections; Enterococcus faecalis; Escherichia coli; Female; Humans; Kidney Calculi; Klebsiella pneumoniae; Magnesium; Magnesium Compounds; Male; Middle Aged; Oxalates; Oxalic Acid; Phosphates; Proteus; Pseudomonas aeruginosa; Pseudomonas Infections; Staphylococcal Infections; Staphylococcus aureus; Streptococcal Infections; Struvite