Selection of antibiotic coverage in vascular patients undergoing cystoscopy

Bacteremic seeding of prosthetic vascular grafts represents a cause for graft infection; transurethral procedures account for one source of bacteremia. Therefore, a prospective study of 200 patients undergoing cystoscopy was conducted to identify the incidence of bacteruria and factors associated with it, organisms involved and their antibiotic sensitivities. Positive cultures were found in 21%. The incidence was 64% in in-patients and 8% in out-patients. Positive cultures were found in 12% of patients who received antibiotics and 29% who did not. Four percent showed signs of bacteremia. The cultures identified both Gram positive and negative organisms; multiple organisms grew in 22%. Gram negative organisms were more common in in-patients. Candida grew in 8%. The Gram positive organisms were sensitive to ampicillin (92%), sulfatrimethoprim (75%) and cefazolin (60%); Gram negative to aminoglycosides (100%) and cefazolin (92%). In view of the unpredictable and multiple organisms, it is recommended that pre-cystoscopy cultures be performed and specific antibiotic coverage be based on the sensitivities.