[Antibiotic prophylaxis in endoscopic urologic surgery]

Recent studies have shown the value of antibiotic prophylaxis with short therapy periods in patients submitted to transurethral surgery. We have carried out a prospective study on 46 patients, all with negative urine cultures prior to the intervention, divided into two groups: one control and the other with short cefuroxime prophylaxis. With the latter a reduction in post-operative infectious complications was obtained, and specifically of postoperative bacteriuria, from a 70% in the control group to al 13% in the prophylaxis group. The results are statistically significant.

Prevention of catheter-associated gram-negative bacilluria with norfloxacin by selective decontamination of the bowel and high urinary concentration

Oral norfloxacin prevented Gram-negative bacilluria in female patients with hip fractures, who needed medium-term transurethral catheterization. This was shown in a placebo-controlled double-blind study of 34 patients. Seventeen of these received a suspension containing 200 mg norfloxacin and 500 mg amphotericin B, twice daily. In the placebo group, six cases of Gram-negative bacilluria had occurred by day 7, as compared with no cases during a median time of catheterization of 23 days in the group on medication. Bacteriuria, either by Gram-positive cocci or by Gram-negative bacilli, was observed in 50% of patients on placebo by day 7; in the treatment group this was the case by day 17 (P less than 0.001). Subsequent bacteriuria with Gram-positive cocci was eliminated by nitrofurantoin (50 mg qid) within four days. Norfloxacin is very suitable for the prevention of Gram-negative bacilluria, because it decontaminates Gram-negative bacilli from the bowel, reaches high concentrations in urine and rarely produces resistant variants.

Are prophylactic antibiotics necessary during extracorporeal shockwave lithotripsy?

A randomised clinical study was carried out on patients admitted for ESWL treatment in order to establish the requirement for prophylactic treatment with antibiotics during this procedure. Patients with clinical signs of urinary tract infection, evidence of infectious stones or a positive urine culture were excluded. All other patients were consecutively randomised into 3 groups which were given either trimethoprim + sulphamethoxazole or mecillinam (Group A), methenamine hippurate (Group B), or no treatment at all (Group C). Evaluation with respect to clinical signs of infection was done immediately after the treatment and 4 weeks later. In addition, a urine culture was performed 2 weeks after ESWL, i.e. 1 week after completing treatment with antibiotics and methenamine hippurate. With respect to infectious complications there were no differences between Groups A and C, between Groups B and C or between Group A and B+C, whereas an unexplained slightly higher infectious rate was recorded for Group B compared with Group A. In all patients the occurrence of bacteriuria was low (6.7%) despite the fact that almost 30% of patients had a ureteric catheter during the ESWL procedure. Patients with ureteric catheters did not present with more infectious complications than those without. All patients had a bladder catheter during ESWL. It was concluded that prophylactic treatment with antibiotics during ESWL treatment is unnecessary in all situations where an infectious aetiology is unlikely.

Evaluation of the retrograde contamination guard in a bacteriologically challenged rabbit model

We compared a newly developed closed urinary drainage system incorporating a retrograde contamination guard (RCG) with the conventional closed drainage system. The new system contains a solid bactericide (povidone iodine) pellet enclosed in a porous cartridge at the drain port of the urine collection bag. A catheterised rabbit model was used. The urine drainage bags were challenged daily for 8 days with an auxotrophically marked uropathogenic strain of Escherichia coli at the outlet tube. The bag urine was infected with the marked organism in 10 of the 11 rabbits in the control group (conventional collection bags) in 3.8 +/- 1.03 days and in only 1 of the 13 rabbits fitted with the RCG. The RCG effectively prevents contamination of the urine drainage bag and thus may play an important role in reducing the incidence of nosocomial urinary tract infections.

Socio-biological correlates of bacteriuria in Saudi pregnant women

Prevalence and socio-biological correlates of bacteriuria in Saudi pregnant women were investigated at King Fahd Hospital of the University, Al-Khobar, Saudi Arabia. Midstream sample specimens of urine were used for identification of significant bacteriuria (greater than or equal to 10.5 organisms of single species per milliliter of urine). The prevalence of bacteriuria was found to be 14.2%. It was more common in women below 20 years of age and among the parous as against the nullipara women. Bacteriuria was significantly associated with socio-economic conditions. It was higher in those with a low family income, of large family size (10+) and living in over-crowded conditions. Only one-fourth (25.8%) of bacteriuric women were symptomatic. Almost half (45.8%) had a past history of urinary tract infection. To identify the problem of urinary tract infection in a vulnerable group of women, as well as to reduce the load on laboratory facilities, it is suggested that routine antenatal screening for bacteriuria should be advocated on a selective basis, i.e. for the young teenage parous women, those coming from disadvantaged socio-economic conditions and in patients with a past history of urinary tract infection.

Asymptomatic bacteriuria in school children

We studied 2447 asymptomatic school children by microscopic examination of urine and culture of a clear voided midstream specimen of urine. Only three children had bacteriuria (0.12%). Urographic abnormalities were detected in both the cases, which could be investigated. This study has shown that asymptomatic bacteriuria is comparatively rare in our community; however where there is bacteriuria, renal damage is common.

[Antibiotic prophylaxis with enoxacin in extracorporeal shockwave lithotripsy]

According to literature, 16 to 35% of operatively removed renal stones harbour bacteria. The efficacy of antibiotic prophylaxis with enoxacin in reducing the rate of bacteriuria after extracorporeal shock wave lithotripsy (ESWL) was investigated in a prospective randomized study. Twenty-five patients received a single 400 mg dose of enoxacin one hour before ESWL, 25 patients did not receive an antibiotic. It was found that a single 400 mg dose of enoxacin one hour before ESWL can reduce the rate of bacteriuria significantly.

New method of postprostatectomy bladder irrigation

Bacterial filters have been used to sterilise the hospital water supply in order to provide irrigant for postprostatectomy irrigation. This method was compared retrospectively to bladder irrigation derived from a still on the ward. Postoperative bacteriuria was similar in both groups of 75 patients, occurring in 23.7% of patients irrigated from the still and in 20% of patients irrigated via the filters. The bacterial filter proved reliable and as safe as using water from the still.

Prophylactic one-dose treatment with clindamycin and gentamicin in transurethral prostatic resection. A double-blind placebo controlled study

One hundred and sixty-eight patients scheduled for transurethral prostatic resection were randomly assigned to treatment either with a combination of clindamycin and gentamycin or with placebo, administered preoperatively as a single bolus infusion. The patients were stratified into a group of 35 with preoperative bacteriuria, and a group of 133 with preoperative sterile urine. Postoperatively the frequency of bacteriuria and bacteriaemia, the maximum body temperature measured, the number of patients with antibiotic therapy instituted, and the duration of hospitalization were significantly lower in the treated than in the placebo group. This applied both to the group with preoperative sterile urine and to the group with preoperative bacteriuria.

[Effectiveness of urine-preserving agents used in water reclamation systems]

The antimicrobial activity of 11 chemicals of different classes was investigated having in view their potential use as urine conserving agents onboard space flying vehicles. The investigations were performed on 8 bacterial cultures, including spore-forming, urease-active bacteria and microorganisms that typically occur in the spacecraft environment. Out of the chemical tested, five haloid-containing agents, primarily oxidative agents, showed the largest spectrum of antimicrobial action and highest bactericidal effect. These agents are recommended to be used as urine conserving agents in water reclamation systems during space flights.

[Peri-operative preventive use of antibiotics in abdominal hysterectomy]

In patients undergoing abdominal hysterectomy, the efficacy of antibiotic prophylaxis was compared to no treatment. Additional studies on the influence of risk factors such as D&C, conisation and IUD's on post-operative morbidity were evaluated. 144 patients were recruited into the study and prospectively randomised into one of four groups. Groups IV and II received 2 g i.v. Cefotetan and were comprised of patients with or without risk factors, respectively. Similarly, groups III and I, again with or without risk factors, received no treatment and served as the control groups. Infectious post-operative morbidity was significantly reduced in both groups of patients receiving antibiotic prophylaxis, the maximum benefit being observed in those patients with accompanying risk factors. The need for additional antibiotic therapy was highest in those patients receiving no antibiotic prophylaxis, i.e. groups III and I. Additionally if concomitant risk factors were present, the duration of hospitalisation was increased by a further 1.4 days.

Single dose, oral antibiotic cover for transurethral prostatectomy

A double-blind, randomised, placebo-controlled study was carried out to determine the incidence and significance of bacteriuria in 110 patients undergoing transurethral resection of the prostate (TURP) and to assess the effect of a single pre-operative dose of Ciprofloxacin, a 4-quinolone antibiotic. Fifteen (68%) of the 22 patients in the placebo group with a positive post-operative urine culture subsequently developed a clinically apparent urinary tract infection (UTI) or received antibiotics in view of a positive urine culture. Adequate prostatic concentrations of Ciprofloxacin were achieved in all who received the drug. A significant reduction in the number of positive post-operative urine cultures and urinary tract infections requiring antibiotic therapy was achieved in this group. Six patients (5.5%) developed clinical evidence of septicaemia, 5 of whom were in the placebo group. No organisms resistant to Ciprofloxacin were encountered. Prior to surgery, 19% of all patients were found to have previously unsuspected bacteriuria. Ciprofloxacin tended to reduce the chances of this group developing a UTI or requiring antibiotics. Further, there was a highly significant reduction in post-operative infective complications in those with sterile urine at the time of resection who had received the drug. This study suggests that antibiotic cover for TURP is of clinical benefit. Ciprofloxacin may prove suited to this purpose, although further experience with the drug is still required.

The use of noxythiolin (Noxyflex 'S') as an antiseptic irrigant in upper urinary tract drainage following percutaneous nephrolithotomy

Percutaneous nephrostomy drainage for the relief of obstruction or stone removal has become a common procedure. Despite the routine use of prophylactic antibiotics, nephrostomy urine frequently becomes infected (approximately 30% of cases). Noxythiolin irrigation has been used to prevent and treat bladder infections. A double-blind, placebo controlled study was carried out in 20 patients undergoing a single-stage percutaneous nephrolithotomy to evaluate the use of noxythiolin as an upper urinary tract antiseptic. In the patients whose nephrostomy tubes were irrigated with a 2.5% solution of noxythiolin, significant bacterial infection was eliminated from the nephrostomy urine and colonisation of the catheter tip was markedly reduced. Noxythiolin also rendered pre-operative infected bladder urine sterile. There were no untoward local or systemic sequelae in either group of patients. This study indicates that irrigation of the upper urinary tract with noxythiolin solution is safe and may be a useful adjunct to reduce the risk of sepsis in patients undergoing percutaneous drainage procedures.

Controlled trial of intravesical noxythiolin in the prevention of infection following outflow tract surgery

A randomised control trial was undertaken in 100 consecutive patients undergoing endoscopic surgery for outflow tract obstruction to assess the efficacy of noxythiolin in preventing post-operative bacteriuria; 1% noxythiolin or sterile water was instilled at the time of catheter removal. The incidence of bacteriuria in the treated group (7/50) was significantly lower than in the control group (19/50). This was statistically significant. This difference was more marked in patients who had been catheterised for retention of urine. There was no difference in the complication rate despite a reduction of infection in the treated group.

Treatment of urinary complications after total joint replacement in elderly females

Urinary retention and the possible consequence of infection after total joint replacement is an important subject to urologists and orthopedic surgeons. A prospective, randomized study was performed in 77 elderly female patients with total joint replacement to test whether twenty-four-hour catheterization perioperatively or straight catheterization postoperatively in the recovery room might reduce the control group's incidence of postoperative urinary tract infection (9%), urinary retention (57%), and subsequent urinary catheterizations. In 16 percent of the patients who had straight catheterization in the recovery room a urinary tract infection developed postoperatively, and 65 percent of these patients required at least one more catheterization with 13 percent requiring a subsequent indwelling Foley catheter. The patients who had perioperative (immediately preoperatively and for 24 hours postoperatively) catheter drainage had a zero incidence of retention and only a 4 percent incidence of urinary tract infection. We recommend this regimen for elderly female patients undergoing total joint replacement under spinal anesthesia.

Postoperative prophylaxis with norfloxacin in patients requiring bladder catheters

The effect of once daily doses of 200 mg oral norfloxacin on the occurrence of catheter-associated bacteriuria (greater than 1000 CFU/ml) and pyuria was studied in 105 post-operative gynaecologic patients. Norfloxacin was given from the second day after surgery until catheter removal. Bacteriuria developed in 32 of 51 (63%) control patients compared to 8 of 54 (15%) patients receiving norfloxacin (p less than 0.001). Pyuria was present in 22 of 51 (43%) control subjects versus only 3 of 54 (5%) patients treated with norfloxacin (p less than 0.001). Bacteria isolated from control patients comprised species of Enterobacteriaceae (40%), Staphylococcus (35%), and Streptococcus (17%); seven isolates were resistant to multiple antibiotics reflecting their nosocomial origin. In contrast, strains isolated from norfloxacin-treated patients comprised non-fermenting gram-negative rods (79%, usually Alcaligenes or Acinetobacter spp.) and faecal streptococci (12%). It is concluded that once daily doses of 200 mg oral norfloxacin are effective in reducing the rate of catheter-associated bacteriuria and pyuria following reconstructive gynaecologic surgery.

Antibiotic prophylaxis in transurethral resection of the prostate with reference to the influence of preoperative catheterization

The value of prophylactic antibiotics in transurethral resection of the prostate (TURP) remains controversial. We have conducted a prospective study in which 308 patients undergoing TURP have been randomized to receive no antibiotic cover (n = 150) or 36 h perioperative cover with temocillin. In 62 patients the urine was found to be infected at the time of operation. In these patients the incidence of postoperative urinary-tract infection (UTI) was 33% in the group who received temocillin, and 87% in the control group (P less than 0.001). In patients with sterile urine at operation (n = 235), the incidence of postoperative UTI was 13% in the temocillin group compared with 24% in the control group (P less than 0.05). Gram-positive organisms were mainly responsible for infection which occurred in patients who had received temocillin. A high incidence of postoperative UTI occurred in patients who had required preoperative catheterization despite the fact that their preoperative urine specimen was sterile. We conclude, (i) prophylactic antibiotics are of benefit in patients undergoing TURP, (ii) the antibiotic administered should be active against both gram-positive and gram-negative organisms, (iii) patients with an indwelling catheter should be considered at a higher risk of infection whether or not organisms are cultured from their preoperative urine specimen.

Comparison of the efficacy of "Trisdine" and kanamycin-colistin bladder instillations in reducing bacteriuria during intermittent catheterisation of patients with acute spinal cord trauma

An open, prospective, randomised, comparative study of "Trisdine" and kanamycin-colistin bladder instillations in reducing significant bacteriuria during intermittent urethral catheterisation was conducted. Trisdine is an aqueous solution of chlorhexidine gluconate 0.01% with added ethylenediaminetetra-acetic acid disodium salt and TRIS buffer at final concentrations of 1.34 mMoles and 0.01 Molar respectively. All patients (15 males and 3 females) admitted with acute spinal cord trauma and bladder involvement requiring intermittent catheterisation for more than 5 days during a 12-month period were studied. There was no significant difference in the mean incidence of significant bacteriuria during intermittent catheterisation in the 7 males who had kanamycin-colistin bladder instillations compared with the 8 males who had Trisdine instillations. A comparison could not be made in the females because there were only 3 patients. Because Trisdine is more stable at ambient temperatures, is less likely to select antibiotic-resistant bacteria and is less expensive, it is concluded that Trisdine is preferable to kanamycin-colistin solution for bladder instillations during intermittent catheterisation.

Effect of silver oxide/trichloroisocyanuric acid antimicrobial urinary drainage system on catheter-associated bacteriuria

We assessed the efficacy of silver oxide coating of the indwelling urethral catheter and catheter adapter, and instillation of trichloroisocyanuric acid into the urinary drainage bag in the prevention of catheter-associated bacteriuria in a prospective and randomized study of 74 patients. Bacteriuria was documented in 29 of the 74 patients (39 per cent). There was a significant difference between the attack rates, with 11 of 41 patients (27 per cent) in the test group and 18 of 33 (55 per cent) in the control group having bacteriuria (p equals 0.02) after a median time to bacteriuria of 36 and 8 days, respectively (p equals 0.01). Urethral meatal colonization was implicated as the source of bladder bacteriuria in 12 of 18 patients (67 per cent) in the control group and 5 of 11 (45 per cent) in the test group. Trichloroisocyanuric acid significantly reduced drainage bag contamination but bag contamination with the same microorganism responsible for bacteriuria preceded infection in only 2 of the 29 patients (7 per cent), 1 in each group. Patients who received systemic antimicrobial agents acquired bacteriuria less frequently than those who did not. The apparent protective effect of systemic antimicrobials was strongest during the first 4 days of catheterization. The data indicate that episodes of bacteriuria arising from the urethral meatus are common among catheterized patients and that the antimicrobial catheter is effective in reducing the incidence of catheter-associated bacteriuria.

Catheter-associated urinary tract infections

The two most common indications for long-term catheterization are recalcitrant urinary incontinence and urinary obstruction that is not corrected by surgery. For incontinent patients, if behavioral changes, nursing care, special clothes, special bed clothes, and medications have not been successful, then a device to collect urine must be considered. For men such a device is a condom catheter; for women an analogous external collection device would be very useful. Suprapubic catheterization may offer an alternative but has been inadequately studied in this patient population. Long-term urinary catheterization has salutary effects for selected patients including patient comfort, family satisfaction, and nursing efficiency and effectiveness. To the patient for whom any physical movement is uncomfortable or painful, and indwelling catheter may be preferable to frequent changes of clothes. Similarly, the family of of severely impaired patients may want to accept the risks of urethral catheterization in order to keep the patient dry. Further, to the extent that the indwelling catheter is effective in decubitus ulcer prevention and/or management, long-term catheterization may diminish the risk of bacteremia or death from soft tissue infection. These benefits of long-term urethral catheterization, in addition to its risks, should be examined in future studies. Once a urethral catheter is in place, even with good catheter hygiene, bacterial entry can be postponed only temporarily; eventually all patients become bacteriuric. Indeed, as the catheter remains in place, organisms continue to enter, others leave or die, and the bacteriuria becomes complex, polymicrobial, and dynamic. Some organisms, particularly recognized uropathogens such as E. coli and K. pneumoniae, appear to reside in the urinary tract itself. Others, such as P. mirabilis, P. stuartii, and M. morganii, probably establish a niche within the urinary catheter, thus increasing their ability to cause subsequent bladder bacteriuria. The complications of long-term urinary catheterization include fevers, acute pyelonephritis, and bacteremias (such as seen in short-term catheterized patients), as well as catheter obstructions, urinary stones, chronic renal inflammation, local periurinary infections, vasicoureteral reflux, renal failure, and, for very long-term catheterized patients, bladder cancer. The thrust of catheter care for the long-term catheterized patient is to prevent complications of the omnipresent bacteriuria. Unfortunately, clinical opportunities for preventing complications are limited.(ABSTRACT TRUNCATED AT 400 WORDS)

Urinary tract infections in urology: a urologist's view of chronic bacteriuria

Urine culture performed during and after antimicrobial therapy will differentiate unresolved urinary tract infections from recurrent infections. Recurrent infections with the same organism and at close intervals are frequently caused by a focus of bacterial persistence within the urinary tract, and infections with different organisms and/or at longer intervals are characteristic of reinfections with bacteria from outside the urinary tract. Unresolved infections are usually due to resistant bacteria and are treated by modification of therapy based on antimicrobial sensitivity testing. When unresolved bacteriuria is caused by organisms sensitive to the initial antimicrobial therapy, azotemia or a large bacterial mass density should be suspected. Recurrent infections at close intervals and/or with the same organism are usually caused by a bacterial focus in an acquired or congenital abnormality of the urinary tract such as infection stones, which must be removed to cure the recurrent infections. If the bacterial focus within the urinary tract cannot be removed, long-term low-dose antimicrobial prophylaxis can prevent the morbidity of recurrent infections. Reinfection requires careful bacteriologic monitoring and low-dose prophylactic, intermittent, or post-intercourse antimicrobial therapy.