Prophylactic antibiotics in transurethral resection of bladder tumors: are they necessary?

Clinical aspects of antimicrobial prophylaxis for invasive urological procedures

The essential value of antimicrobial prophylaxis is to defend the patient undergoing invasive diagnostic procedures or surgery against infectious complications by reducing the bacterial load. Escherichia coli remains the predominant uropathogen (70-80%) isolated in acute community-acquired uncomplicated infections, followed by Staphylococcus saprophyticus (10 to 15%). Klebsiella, Enterobacter, Proteus species, and enterococci infrequently cause uncomplicated cystitis and pyelonephritis. The pathogens traditionally associated with UTI are altering many of their features, particularly because of antimicrobial resistance. Currently, only transurethral resection of prostate and prostate biopsy has been well studied and has high and moderately high levels of evidence in favor of using antibiotic prophylaxis. Other urological interventions have not been well studied. The moderate to low evidence suggests that there is no need for antibiotic prophylaxis in cystoscopy, urodynamic investigations, and extracorporeal shock-wave lithotripsy, whereas the low evidence favors the use of antibiotic prophylaxis for therapeutic ureterorenoscopy and percutaneous nephrolithotomy. The scarce data from studies on transurethral resection of bladder tumors cannot provide a definitive indication for antibiotic prophylaxis for this intervention.

[Antibiotic prophylaxis in urology]

INTRODUCTION

Antibiotic prophylaxis (AP) is used to minimize infectious complications resulting from interventions. Due to high rates of development of bacterial resistance and side effects, the use of antibiotics must be weighed on the basis of high levels of evidence. The main endpoints of urology AP are the prevention of symptomatic urogenital infections, urosepsis and wound infections. The purpose of this review is to bring objectives, principles and recommendations on urology AP according to the latest scientific evidence.

METHODS

We carried out a systematic search of MEDLINE, EMBASE and the Cochrane Library using keywords such as AP, prophylaxis, antibiotics, urological surgery, urogenital surgery and the names of the urologic procedures. The results of studies on the AP for each procedure were classified according to the levels of evidence and grades of recommendation from the European Association of Urology.

RESULTS

There are a number of good quality studies on AP about endoscopic resection of the prostate (TURP), urodynamic studies and transrectal prostate biopsies (trPB). The majority of the studies about other procedures have several limitations (sample size, consistency of definitions, statistics and trial design). Lack of consistency in the definitions of infectious complications does not allow comparison between different studies.

CONCLUSIONS

The AP is evidence-based is indicated only for TURP and trPB. It is desirable to perform randomized, prospective and controlled trials in order to rationalize the use of antibiotics, improve the cost/benefit ratio and reduce bacterial antibiotic resistances.

Aetiology and antibiotic resistance issues regarding urological procedures

There are specific indications in urological procedures [transurethral resection of the prostate (TURP), transurethral resection of the bladder (TURB), endoscopic procedures, and all interventions classified as contaminated or dirty] requiring antibiotic prophylaxis. Most postoperative infections are caused by enterococci of the Gram-positive strains and Enterobacteriaceae of the Gram-negative ones. As reported by the European Center for Disease Prevention and Control (ECDC), there are increasing numbers of antibiotic-resistant pathogens. Most Enterococcus faecium strains are ampicillin-resistant and the Enterobacteriaceae have a high prevalence of extended-spectrum beta-lactamase (ESBL) producers, for which the cephalosporins and penicillins are not drugs of choice. In recent years, there are also increasing numbers of Gram-negative strains that are able to produce carbapenemases and for which the only therapeutic options are gentamicin, tigecycline and colistin. An alternative to these drugs, from a prophylactic point of view, is fosfomycin, an old antibiotic that maintains bactericidal activity against both enterococci and multidrug-resistant Enterobacteriaceae. Available in an oral formulation as trometamol salt, fosfomycin reaches high plasma and urine concentrations, and is therefore a possible alternative to other drugs both for therapy and urological prophylaxis.

Antibiotic prophylaxis in urologic procedures: a systematic review

OBJECTIVE

Antibiotic prophylaxis is used to minimize infectious complications resulting from interventions. Side-effects and development of microbial resistance patterns are risks of the use of antibiotics. Therefore, the use should be well considered and based on high levels of evidence. In this review, all available evidence on the use of antibiotic prophylaxis in urology is gathered, assessed, and presented in order to make choices in the use of antibiotic prophylaxis on the best evidence currently available.

METHODS

A systematic literature review was conducted, searching Medline, Embase (1980-2006), the Cochrane Library, and reference lists for relevant studies. All selected articles were reviewed independently by two, and, in case of discordance, three, reviewers.

RESULTS

Only the transurethral resection of prostate (TURP) and prostate biopsy are well studied and have a high and moderate to high level of evidence in favour of using antibiotic prophylaxis. Other urologic interventions are not well studied. The moderate to low evidence suggests no need for antibiotic prophylaxis in cystoscopy, urodynamic investigation, transurethral resection of bladder tumor, and extracorporeal shock-wave lithotripsy, whereas for therapeutic ureterorenoscopy and percutaneous nephrolithotomy, the low evidence favours the use of antibiotic prophylaxis. Urologic open and laparoscopic interventions were classified according to surgical wound classification, since no studies were identified. Antibiotic prophylaxis is not advised in clean surgery, but is advised in clean-contaminated and prosthetic surgery.

CONCLUSIONS

Except for the TURP and prostate biopsy, there is a lack of well-performed studies investigating the need for antibiotic prophylaxis in urologic interventions.

[Urinary bacteriologic study prior to endoscopic urologic surgery]

OBJECTIVE

The objectives of this study are to know the incidence of preoperative bacteriuria in patients undergoing endoscopic urologic surgery, to analyze the most frequent microorganisms appearing in the cultures and their resistance to antibiotics in order to select the most appropriate prophylactic one for our population, and to determine the risk factors related to postoperative bacteriuria or sepsis of urologic origin.

MATERIAL AND METHODS

449 patients undergoing endoscopic urologic surgery were included in the study. Urinary samples were collected for culture prior to prophylactic antibiotic administration and again a week after bladder catheter removal once the antibiotic treatment was finished. Variables related to an increase in infectious complications were analyzed. Special attention was paid to postoperatory incidences, mainly those of infectious nature.

RESULTS

Preoperative bacteriuria was found in 66 out of 428 patients (15.4%). It was found to be related to age, sex, previous infection episodes, diabetes mellitus, indwelling catheter and to the pathology for which operation was indicated. The most frequently found microorganism was Escherichia Coli. Resistance to prophylactic antibiotic was found in 37.9% of patients with preoperatory bacteriuria. Postoperatory bacteriuria, observed in 22.0% of the patients was exclusively related to preoperatory bacteriuria. 2.9% of patients showed sepsis of urinary origin criteria during hospital staying, and it was found to be exclusively related to length of surgery and neither to preoperatory bacteriuria nor to indwelling catheter time or the "inappropriate" prophylactic antibiotic use in these cases.

CONCLUSIONS

A good part of patients who underwent endoscopic surgery showed preoperatory bacteriuria, responsible for postoperative bacteriuria in less than 25% of the cases. The length of surgery seemed to be the only related cause whit sepsis of urinary origin.

Perioperative antibiotic prophylaxis for transurethral resection of the prostate: is it justifiable?

The role of perioperative antimicrobial prophylaxis in transurethral resection of the prostate remains controversial. A total of 110 patients with preoperative sterile urine undergoing transurethral resection of the prostate was included in this open, prospective and randomized study to compare the prophylactic role of cefoperazone to no antibiotic prophylaxis. Patients were well matched between the 2 groups on all essential characteristics and risk factors at baseline. Owing to the strict selection criteria and aseptic measures used, the low incidence of postoperative urinary tract infections in the control group (1.8 per cent) compared to none in the cefoperazone group made conclusions and generalization limited due to sample size. In view of the extremely low infection rate it is doubtful that antibiotic prophylaxis had any beneficial role in this selected population.