Urogenital Infections and Inflammations

T.E. Bjerklund Johansen, F. M.E. Wagenlehner, Y.-H. Cho, T. Matsumoto, J. N. Krieger, D. Shoskes, K. Naber

Asymptomatic bacteriuria in hospitalized patients

 Riccardo Bartoletti 1
Tommaso Cai 2
Florian M. E. Wagenlehner 3
Truls Erik Bjerklund Johansen 4

1 Department of Translational Research and New Technologies, University of Pisa, Pisa, Italy
2 Dept. of Urology, Santa Chiara Regional Hospital, Trento, Italy
3 Clinic of Urology and Andrology, Justus-Liebig University of Giessen, Gießen, Germany
4 Urology Department, Oslo University Hospital, Oslo, Norway


Asymptomatic Bacteriuria (ABU) in hospitalized patients is a relatively frequent event and is mainly seen in patients with co-morbidities.

This chapter incorporates the 2016 Guidelines on Urological Infections of the European Association of Urology and the latest Guideline of the Infectious Diseases Society of America for the management of ABU. A systematic literature search in Medline, Cochrane and Embase was also carried out. The following keywords were used: ABU and hospitalized/inpatients, ABU and elderly institutionalized residents, ABU and diabetes, ABU and urinary stents/catheters, ABU and stones, ABU and surgical procedures, ABU and renal transplantation, ABU and spinal cord injury. A total of 849 publications were identified and screened by title and abstract. 32 papers were included in the review.

The host immune response in patients with ABU is less intense than usually found in patients with symptomatic urinary tract infections. ABU is more frequent in patients with dementia and pulmonary diseases, and related to well known risk factors for urinary tract infections such as diabetes, presence of permanent urinary devices, infected stones, spinal cord injury, and renal transplantation.

In conclusion, ABU is common in hospitalized patients. Elderly subjects have an increased prevalence of ABU, presumably secondary to concomitant diseases and conditions such as diabetes, urinary retention, urinary incontinence and/or indwelling urinary catheters. In most cases ABU should not be treated with antibiotics. According to the principles of antibiotic stewardship alternative therapeutic approaches should be adopted in hospitalized patients with ABU.

Summary of recommendations

  • ABU in hospitalized patients and elderly institutionalized residents is frequently associated with concomitant co-morbidities (LoE 1b).
  • Antimicrobial treatment does not have significant benefits in terms of re-infection or uro-sepsis episodes in these patients (LoE 1b, GoR A).
  • ABU is associated with an increased risk of urosepsis in women with diabetes; but treatment of ABU does not reduce the risk of symptomatic infections (LoE 2b, GoR B).
  • Patients with ABU and risk factors such as permanent urinary devices (stents, catheters, nephrostomy tubes), infected urinary stones and spinal cord injury, should not be treated with antibiotics.
  • ABU in kidney transplant patients should not be treated after the first month – it is unknown whether it needs to be treated during the first month (LoE 1b, GoR A) (LoE 1b, GoR A).
  • ABU should be treated in patients supposed to undergo endourological procedures with mucosal breakage (LoE 1b, GoR A).

1 Introduction

The term asymptomatic bacteriuria (ABU) means that one or more bacterial strains have been identified in the urine samples of patients without symptoms of Urinary Tract Infection (UTI) [1]. The critical number of colony forming units is 105 in women and men. The prevalence of ABU varies widely in the population and is related to age and presence of significant co-morbidities. Screening and treatment of ABU is generally recommended only during pregnancy [2] and in the preoperative evaluation of men before selected urological procedures [3]. Hospitalized patients may develop ABU related to community-acquired infections, as well as from atypical bacterial strains such as ESBL resistant E. coli, Carbapenemase resistant Klebsiella pneumoniae or other combined infections often seen in institutions. The microbiological criterium for the diagnosis of ABU in men is not well validated but bacterial concentrations in urine in the range from 103 to 105 cfu/mL in a single voided urine specimen have been suggested (reproducible in 98% of asymptomatic outpatients when the culture is repeated within a week) whereas it should be >105 cfu/mL in two consecutive urine specimens in women [4], [5], [6]. Pyuria is a sign of inflammation in the genitourinary tract and is commonly found in subjects with ABU but also in other genitourinary tract diseases with negative urine cultures. Thus, pyuria only is not sufficient to diagnose bacteriuria and the presence or absence of pyuria does not differentiate symptomatic from asymptomatic urinary tract infections [1].

ABU in hospitalized patients is relatively common and is mainly associated with the presence of co-morbidities. It is often seen in elderly people and in patients with urinary tract obstruction and/or urinary incontinence, many of whom are candidates for urological surgical procedures.

Despite the fact that several guidelines regard the test to be of paramount importance to prevent development of UTIs after the procedure, urine culture tests are not always performed before urological procedures [7].

Host variables and bacteria-related virulence factors may be associated with an increased risk of developing ABU in hospitalized patients.

2 Methods

This chapter incorporates the 2014 Guidelines on Urological Infections of the European Association of Urology (EAU) and the latest Infectious Diseases Society of America Guideline for the management of ABU [1], [7]. Moreover, a systematic literature search in Medline, Cochrane, and Embase has been carried out. The following keywords were used: ABU and hospitalized/inpatients, ABU and elderly institutionalized residents, ABU and diabetes, ABU and urinary stents/catheters, ABU and stones, ABU and surgical procedures, ABU and renal transplantation, ABU and spinal cord injury. The limitations used were age over 18 years, clinical studies, English language and peer reviewed papers. A total of 849 publications were identified, and screened by title and abstract. 32 papers were included in the review. The studies were rated according to the level of evidence (LoE) and the grade of recommendation (GoR) according to ICUD standards.

3 Results

The outcome of our systematic review is presented and discussed for separate clinical situations.

3.1 Patient characteristics and virulence factors

The host immune response in patients with asymptomatic bacteriuria seems to be less than in patients with symptomatic urinary tract infection. Proteomic data obtained from urine sediment of 120 subjects demonstrated a substantial inflammatory and antimicrobial immune response with high abundance of proteins from activated neutrophils (associated with pathogens in most cases) and confirmed leukocyte esterase activities and abnormal leukocyte counts at microscopy [8]. Lutay and co-workers found that asymptomatic bacteriuria strain inoculated in human cells is capable of activating a broad suppression of RNA-polymerase II-dependent host gene expression with a subsequent reduced host immune response in comparison with acute pyelonephritis strains [9]. The same results have been found by other authors. The innate host immune response was evaluated in 23 patients with asymptomatic bacteriuria generated by inoculation of nonvirulent E. coli 83972 strain. Cytokine/chemokine levels were analyzed in the urine of these patients prior to and after strain inoculation. The authors concluded that the host immune response in patients with asymptomatic bacteriuria is determined by innate immune mediators and that host genetic variability influences the quantifying response [10]. Dobrindt and co-workers confirmed these data and demonstrated that adaptation of E. coli 83972 to prolonged growth in the urinary tract involves responses to specific growth conditions present in the individual host [11].

Other variables originating from bacterial virulence factors should also be considered. Bacterial strains isolated from healthy schoolgirls or hospitalized urology patients with ABU were compared with commensal strains isolated from the intestinal flora of children without urinary infection. All isolates from the two populations affected by asymptomatic bacteriuria had similar virulence genetic characteristics but uropathogenic E. coli virulence genes were less frequently attenuated in the hospital strains [12]. These results indicate that some ABU related strains undergo a programmed reductive evolution within human hosts and hospitalized patients seem to have higher susceptibility to aggressive infections [13]. Marschall and co-workers demonstrated that E. coli related ABU was frequent and more common in patients with dementia and chronic pulmonary disease in a 12-month prospective cohort study on adult inpatients in a tertiary care hospital. Their conclusion was that patient characteristics but not virulence factors discriminate between asymptomatic and symptomatic E. coli bacteriuria in the hospital setting [14].

3.2 Elderly institutionalized residents

Some studies aimed to determine the effects of eradicating ABU in nursing home residents regarding the severity of chronic urinary incontinence, infection recurrence, behavioral changes and mortality among non-catheterized men [15], [16], [17], [18], [19].

The results of these studies demonstrated that eradicating bacteriuria had no short term effects on the severity of chronic urinary incontinence among nursing home residents. Ouslander and co-workers found that ABU was temporarily eradicated in about 40% of residents by immediate 6-day antibiotic therapy and another 10% of subjects had persistent ABU after the therapy. The presence of pyuria did not affect the results [15].

Another report evaluated the effectiveness of antimicrobial therapy in decreasing the episodes of bacterial reinfection. The authors found that untreated women experienced higher rates of bacteriuria than those treated by antibiotic therapy but episodes of reinfection as well as adverse events were more common in the treated group [16]. These data suggest that in elderly institutionalized women, bacteriuria is persistent and antimicrobial therapy is harmful and more costly.

Similarly, antimicrobial treatment did not show improvement in physical or mental function and did not significantly change the proportion of patients without bacteriuria compared with placebo (21% vs. 32%) [19]. Moreover, other authors confirmed that mortality was not significantly different among subjects undergoing antimicrobial therapy and subjects undergoing no treatment [17].

Although the institutionalized elderly non-catheterized population has a higher prevalence of ABU, antimicrobial treatment does not appear to have significant benefits for clinical outcomes [20].

3.3 The role of diabetes in hospitalized patients

Patients with diabetes have increased risk of urinary tract infections. Most UTIs in diabetic patients are community acquired infections and patients are treated as outpatients. ABU is often diagnosed by routine urine examination in hospitalized patients. Other host factors that enhance the risk of UTI in diabetics include age, poor metabolic control, and long term complications such as diabetic nephropathy and cystopathy. Subjective symptoms such as frequency and dysuria may be related to these complications rather than bacteriuria. Thus ABU episodes may be misidentified as symptomatic infection. Autonomic neuropathy involving the genitourinary tract as a consequence of diabetes may result in dysfunctional voiding and urinary retention which decrease the physical bacterial clearance through micturition, thereby facilitating bacterial growth [21].

Elevated glucose concentrations in urine may promote the growth of pathogenic bacteria. Various impairments in the immune system including humoral, cellular, and innate immunity may further contribute to the pathogenesis of ABU and UTI in diabetic patients.

Although ABU has been found to be associated with an increased risk of hospitalization for urosepsis in a prospective observational study among women with diabetes, treatment of ABU did not reduce the risk of symptomatic urinary tract infections [21].

A recently published meta-analysis investigated whether ABU is truly more common in patients with diabetes than among control subjects. 6,281 patients from 21 articles were studied. ABU was present in 12.2% of subjects with diabetes and in 4.5% of controls, with an odds ratio of 3.0 (95% CI 1.1–8) in patients with type I diabetes and 3.2 (2.0–5.2) in patients with type II diabetes as compared to control subjects [22].

3.4 Patients with permanent urinary devices

Urinary infections account for about 40% of hospital acquired/nosocomial infections, and about 80% of urinary tract infections acquired in hospitals are associated with urinary catheters or other devices [23].

Although catheter-associated urinary tract infections (CAUTI) and catheter associated asymptomatic bacteriuria (CAABU) are clinically distinct entities, most papers describing the risk of bacteriuria do not distinguish between them [24]. Kizilbash and co-workers investigated 444 episodes of catheter-associated bacteriuria in 308 patients in a retrospective cohort study with 30 days followup after identification of a positive urine culture. 128 (41.6%) patients had CAUTI, and 180 (58.4%) had CAABU. Three episodes of bacteriuria were followed by bacteremia from a urinary source (0.7%). CAUTI, rather than CAABU, was associated with bacteremia from any source, but neither CAUTI nor CAABU predicted subsequent mortality. Use of antimicrobial agents to treat bacteriuria was not associated with either bacteremia from any source or mortality [24]. Kidd and co-workers investigated the advantages and disadvantages of alternative routes of short term bladder catheterization in adults in terms of infections, adverse events, replacement, duration of use, participant satisfaction, and cost effectiveness. Participants with indwelling catheters had more cases of asymptomatic bacteriuria (RR 2.25, 95% CI 1.63 TO 3.10), although the duration of catheterization was shorter in the indwelling urethral catheter group [25]. On the other hand, some authors demonstrated that ABU overtreatment was greater in the long-term care patients (51.8%) than acute care (30.8%), suggesting a need for increased attention to antibiotic stewardship. Appropriate interventions are able to determine a significant reduction of ABU overtreatment in long-term care (from 1.6 to 0.6 per 1,000 bed-days) [26].

Nephrostomy tube placement has a lower risk of subsequent pyelonephritis compared to urethral catheter placement, although ABU is present in 7.5% [27]. Bahu et al. found 89% ABU events in patients with primary nephrostomy tube placement, and rarely in patients who underwent nephrostomy tube exchange [27]. These results seem to be paradoxical considering the increased risk of slime production and intrarenal migration during a nephrostomy tube replacement manoeuvre. Other authors compared the effect of nephrostomy tube change on the occurrence of asymptomatic bacteremia. They found asymptomatic bacteremia in 11% of cases and no significant effect of antibiotic prophylaxis in bacteremia prevention [28].

Ureteral stenting seems to be unrelated to the frequency of ABU episodes except in patients who have undergone kidney transplantation. These patients have a high incidence of bacteriuria during the first month after transplantation (56.7%) and ABU in a long term period is seen in about 40% of cases [29], [30]. The most common organism is E. coli (40%), but there are also many cases of Klebsiella infection (19%). The high incidence of bacteriuria during the early post–kidney transplant period requires increased awareness and surveillance [29].

3.5 Patients with infected stones

Otherwise asymptomatic renal stones may be the cause of bacteriuria. This relationship should be considered before surgical removal of a stone in patients with bacteriuria. Hugosson and co-workers separated stone related infections (70%) from regular lower urinary tract infections (30%) by ureteral catheterization. Even very small stones were shown to be the cause of decade-long bacteriuria with encouraging results obtained from stone removal (87% of infections were eradicated) [31]. In such cases the presence of urinary stones facilitates the formation of small bacterial sanctuaries without being necessarily related to the physical features of the stones.

Urinary stone formation is otherwise closely related to complicated urinary tract infections (urinary obstruction, neurogenic bladder disorders, urinary diversions, indwelling catheters) due to urease-producing bacteria. Infected urinary stones (struvite, carbonate apatite, ammonium urate) are regularly associated with UTI.

Some studies investigated ABU in patients with urinary stones and without associated risk factors who underwent extracorporeal shock wave lithotripsy (ESWL). Mira Moreno reported only 4.6% incidence of ABU suggesting that antibiotic prophylaxis is not justified in these patients unless there are well-defined risk factors [32]. The American Urological Association guidelines recommend universal antibiotic prophylaxis, whereas the European Association of Urology guidelines recommend prophylaxis only for selected patients. Honey and co-workers investigated 526 patients who underwent ESWL for urolithiasis. Urine dipstick and culture excluded infection in 389 of them. Only 2.8% of patients developed ABU and just one patient got a symptomatic urinary infection [33].

3.6 Candidates for surgical procedures (urology, orthopedic, renal transplantation)

Patients with ABU who undergo traumatic genitourinary procedures associated with mucosal bleeding have a high rate of postprocedure bacteremia and sepsis [1]. Bacteremia occurs in up to 60% of bacteriuric patients who undergo prostate trans-urethral resection, and there is clinical evidence of sepsis in 6–10% of these patients [34]. The effectiveness of antimicrobial treatment in preventing these complications is well documented [35].

There is little information concerning other procedures but any intervention involving mucosal bleeding should be considered to increase the risk of developing bacteriuria and infection [36]. Recent studies demonstrated that treatment of bacteriuria is not indicated prior to minor urologic interventions which do not imply mucosal trauma. Bacteriuria was present in 25% of patients who were candidates for BCG intravesical administration and in 17% of subjects who were candidates for cystoscopy [37].

Pretreatment of ABU is not beneficial for minor procedures (e.g. replacement of a long-term indwelled catheter), but it is mandatory for major surgeries such as transurethral prostatectomy and procedures where the urinary tract is opened [1]. Antibiotic prophylaxis should be given with appropriate dosage and timing. In the absence of an indwelled catheter, antimicrobial prophylaxis can be discontinued immediately after the procedure [35], [38], [39]. Conversely, if the indwelling catheter remains in place after prostate resection, some investigators recommend extended prophylaxis until the catheter is removed [34], [38].

Orthopaedic surgery is relatively frequent in the elderly and some authors investigated the efficacy of preoperative antimicrobial treatment in patients with ABU who underwent hip replacement surgery [40]. They evaluated the risk of wound infection related to the presence of asymptomatic bacteriuria. They found wound contamination in 6% of treated bacteriuric patients and in 4.8% of those without antibiotic treatment, respectively. Thus ABU is not a cause of postoperative orthopedic surgical site infection and treatment of bacteriuria prior to surgery is not required. Other authors prospectively evaluated 215 consecutive patients who underwent knee arthroplasty. ABU was diagnosed in 11 out of 215 patients (5.1%) and four of these were treated with tailored antibiotics. No significant differences between the two groups of patients were found [41].

Renal transplanted patients have an increased risk of developing bacteriuria as previously described. Almost half of all urinary infections found in transplant patients are diagnosed during the first month following transplantation [42]. In particular, ABU occurred in about 65% of cases. The most frequent bacteria are Enterococcus spp. (33%) and E. coli (31%). Female gender, previous cytomegalovirus infection and a history of an acute rejection episode are independent risk factors for the development of post-transplant urinary infection [42]. It is not clear whether ABU during the first month after transplantation is related to the specific type of surgery with immune depression or the presence of ureteral stenting. ABU is usually found long-term in 40% of patients [29], [30]. Some authors demonstrated an increased risk of symptomatic urinary infection after appropriate antibiotic treatment of ABUs [43]. Origuen et al. recently demonstrated that systematic screening and treatment of ABU beyond the second month after transplantation provided no apparent benefit among kidney transplantation recipients [44].

3.7 Spinal cord injured patients

Subjects with spinal cord injuries have a high prevalence of ABU [45], [46]. Several studies have shown poor effect of antibiotic therapy in the prevention of subsequent symptomatic urinary infections or ABU recurrences. After 7–14 days of antibiotic therapy 93% of subjects were bacteriuric again within 30 days of the completion of the treatment whereas 85% were bacteriuric within 30 days after a 28 day-course [45]. Reinfection strains showed increased antibiotic resistance.

Two randomized studies in patients with ABU using intermittent catheterization showed no difference between antibiotic treatment and placebo on the rates of symptomatic infection and bacteriuria [47] , [48].

Despite the limited number of clinical trials available in this group of patients, the results obtained uniformly recommend antibiotic treatments of symptomatic infections in spinal cord injured patients [1].

Lavado and co-workers recently demonstrated that moderate-intensity aerobic physical training is effective on ABU recurrences in patients with C8 to T12 spinal cord injury with a significant reduced prevalence from 52.3 to 14.2%. The mechanism by which this occurs is not clear [49].

4 Further research

The main aspects of asymptomatic bacteriuria are related to ASB as a risk factor for development of severe infections on one side, and to overtreatment and antibiotic stewardship on the other. Future research should address the importance of the whole urinary microbiome in patient situations where ASB has a role. We also need more data about the immune response to ABU. Finally, we must explore the effects of adherence to present guidelines recommendations and study the effects of non-antibiotic measures in patients with ASB.

5 Conclusions

ABU is a common finding in hospitalized patients. Elderly subjects have an increased risk of developing ABU, usually attributable to concomitant diseases such as indwelling urinary catheter, diabetes, urinary retention and urinary incontinence.

ABU is also frequent in patients who undergo urological surgical procedures with mucosal bleeding including TURP and prostate biopsy. Stone disease seems to be related to ABU only in the case of urinary tract obstruction including renal calyxes, whereas patients who previously underwent renal transplantation need attention due to the risk of developing significant infections during short and long term followup.

In many cases ABU should not be treated with antibiotics. Exceptions are before mucosa breaking surgery and in transplant patients during the first month after the surgery.

Alternative treatments other than antibiotics should be explored, investigated and adopted to reduce the risk of developing significant infections in hospitalized patients as well as outpatients with ABU.

6 Acknowledgements

We acknowledge Lindsay Nicolle for constructive criticism of the manuscript.


[1] Nicolle LE, Bradley S, Colgan R, Rice JC, Schaeffer A, Hooton TM; Infectious Diseases Society of America; American Society of Nephrology; American Geriatric Society. Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults. Clin Infect Dis. 2005 Mar;40(5):643-54. DOI: 10.1086/427507
[2] Lin K, Fajardo K. Screening for Asymptomatic Bacteriuria in Adults: Evidence for the U.S. Preventive Services Task Force Reaffirmation Recommendation Statement. Annals of Internal Medicine. 2008 Jul 1;149(1):W-20. DOI: 10.7326/0003-4819-149-1-200807010-00009-w1
[3] Nicolle LE. Asymptomatic bacteriuria: review and discussion of the IDSA guidelines. Int J Antimicrob Agents. 2006 Aug;28 Suppl 1:S42-8. DOI: 10.1016/j.ijantimicag.2006.05.010
[4] Gleckman R, Esposito A, Crowley M, Natsios GA. Reliability of a single urine culture in establishing diagnosis of asymptomatic bacteriuria in adult males. J Clin Microbiol. 1979 May;9(5):596-7.
[5] Rubin RH, Shapiro ED, Andriole VT, Davis RJ, Stamm WE. Evaluation of new anti-infective drugs for the treatment of urinary tract infection. Infectious Diseases Society of America and the Food and Drug Administration. Clin Infect Dis. 1992 Nov;15 Suppl 1:S216-27.
[6] Hooton TM, Scholes D, Stapleton AE, Roberts PL, Winter C, Gupta K, Samadpour M, Stamm WE. A prospective study of asymptomatic bacteriuria in sexually active young women. N Engl J Med. 2000 Oct;343(14):992-7. DOI: 10.1056/NEJM200010053431402
[7] Grabe M, Bartoletti R, Bjerklund-Johansen TE, Çek HM, Pickard RS, Tenke P, Wagenlehner F, Wullt B. Guidelines on Urinary Infections. Arnhem: European Association of Urology; 2014. Available from: https://uroweb.org/wp-content/uploads/19-Urological-infections_LR.pdf
[8] Yu Y, Sikorski P, Bowman-Gholston C, Cacciabeve N, Nelson KE, Pieper R. Diagnosing inflammation and infection in the urinary system via proteomics. J Transl Med. 2015 Apr;13:111. DOI: 10.1186/s12967-015-0475-3
[9] Lutay N, Ambite I, Grönberg Hernandez J, Rydström G, Ragnarsdóttir B, Puthia M, Nadeem A, Zhang J, Storm P, Dobrindt U, Wullt B, Svanborg C. Bacterial control of host gene expression through RNA polymerase II. J Clin Invest. 2013 Jun;123(6):2366-79. DOI: 10.1172/JCI66451
[10] Grönberg-Hernández J, Sundén F, Connolly J, Svanborg C, Wullt B. Genetic control of the variable innate immune response to asymptomatic bacteriuria. PLoS One. 2011;6(11):e28289. DOI: 10.1371/journal.pone.0028289
[11] Dobrindt U, Wullt B, Svanborg C. Asymtomatic Bacteriuria as a Model to Study the Coevolution of Hosts and Bacteria. Pathogens. 2016 Feb 15;5(1). pii: E21. DOI: 10.3390/pathogens5010021
[12] Salvador E, Wagenlehner F, Köhler CD, Mellmann A, Hacker J, Svanborg C, Dobrindt U. Comparison of asymptomatic bacteriuria Escherichia coli isolates from healthy individuals versus those from hospital patients shows that long-term bladder colonization selects for attenuated virulence phenotypes. Infect Immun. 2012 Feb;80(2):668-78. DOI: 10.1128/IAI.06191-11
[13] Wagenlehner FM, Naber KG. Editorial commentary: asymptomatic bacteriuria--shift of paradigm. Clin Infect Dis. 2012 Sep;55(6):778-80. DOI: 10.1093/cid/cis541
[14] Marschall J, Piccirillo ML, Foxman B, Zhang L, Warren DK, Henderson JP; CDC Prevention Epicenters Program. Patient characteristics but not virulence factors discriminate between asymptomatic and symptomatic E. coli bacteriuria in the hospital. BMC Infect Dis. 2013 May;13:213. DOI: 10.1186/1471-2334-13-213
[15] Ouslander JG, Schapira M, Schnelle JF, Uman G, Fingold S, Tuico E, Nigam JG. Does eradicating bacteriuria affect the severity of chronic urinary incontinence in nursing home residents? Ann Intern Med. 1995 May;122(10):749-54.
[16] Nicolle LE, Bjornson J, Harding GK, MacDonell JA. Bacteriuria in elderly institutionalized men. N Engl J Med. 1983 Dec;309(23):1420-5. DOI: 10.1056/NEJM198312083092304
[17] Nicolle LE, Mayhew WJ, Bryan L. Prospective randomized comparison of therapy and no therapy for asymptomatic bacteriuria in institutionalized elderly women. Am J Med. 1987 Jul;83(1):27–33. DOI: 10.1016/0002-9343(87)90493-1
[18] Nicolle LE, Mayhew JW, Bryan L. Outcome following antimicrobial therapy for asymptomatic bacteriuria in elderly women resident in an institution. Age and Ageing. 1988;17(3):187–92. DOI: 10.1093/ageing/17.3.187
[19] Potts L, Cross S, MacLennan WJ, Watt B. A double-blind comparative study of norfloxacin versus placebo in hospitalised elderly patients with asymptomatic bacteriuria. Arch Gerontol Geriatr. 1996 Sep;23(2):153–61. DOI: 10.1016/0167-4943(96)00715-7
[20] Dull RB, Friedman SK, Risoldi ZM, Rice EC, Starlin RC, Destache CJ. Antimicrobial treatment of asymptomatic bacteriuria in noncatheterized adults: a systematic review. Pharmacotherapy. 2014 Sep;34(9):941-60. DOI: 10.1002/phar.1437
[21] Nitzan O, Elias M, Chazan B, Saliba W. Urinary tract infections in patients with type 2 diabetes mellitus: review of prevalence, diagnosis, and management. Diabetes Metab Syndr Obes. 2015;8:129-36. DOI: 10.2147/DMSO.S51792
[22] Renko M, Tapanainen P, Tossavainen P, Pokka T, Uhari M. Meta-analysis of the significance of asymptomatic bacteriuria in diabetes. Diabetes Care. 2011 Jan;34(1):230-5. DOI: 10.2337/dc10-0421
[23] Lusardi G, Lipp A, Shaw C. Antibiotic prophylaxis for short-term catheter bladder drainage in adults. Cochrane Database of Systematic Reviews. 2013 Jul 3. DOI: 10.1002/14651858.CD005428.pub2
[24] Kizilbash QF, Petersen NJ, Chen GJ, Naik AD, Trautner BW. Bacteremia and mortality with urinary catheter-associated bacteriuria. Infect Control Hosp Epidemiol. 2013 Nov;34(11):1153-9. DOI: 10.1086/673456
[25] Kidd EA, Stewart F, Kassis NC, Hom E, Omar MI. Urethral (indwelling or intermittent) or suprapubic routes for short-term catheterisation in hospitalised adults. Cochrane Database Syst Rev. 2015 Dec 10;(12):CD004203. DOI: 10.1002/14651858.CD004203.pub3
[26] Trautner BW, Grigoryan L, Petersen NJ, Hysong S, Cadena J, Patterson JE, Naik AD. Effectiveness of an Antimicrobial Stewardship Approach for Urinary Catheter-Associated Asymptomatic Bacteriuria. JAMA Intern Med. 2015 Jul;175(7):1120-7. DOI: 10.1001/jamainternmed.2015.1878
[27] Bahu R, Chaftari AM, Hachem RY, Ahrar K, Shomali W, El Zakhem A, Jiang Y, AlShuaibi M, Raad II. Nephrostomy tube related pyelonephritis in patients with cancer: epidemiology, infection rate and risk factors. J Urol. 2013 Jan;189(1):130-5. DOI: 10.1016/j.juro.2012.08.094
[28] Cronan JJ, Horn DL, Marcello A, Robinson A, Paolella LP, Lambiase RE, Haas RA, Opal S, Dorfman GS. Antibiotics and nephrostomy tube care: preliminary observations. Part II. Bacteremia. Radiology. 1989 Sep;172(3 Pt 2):1043-5. DOI: 10.1148/172.3.1043
[29] Parapiboon W, Ingsathit A, Jirasiritham S, Sumethkul V. High incidence of bacteriuria in early post-kidney transplantation; results from a randomized controlled study. Transplant Proc. 2012 Apr;44(3):734-6. DOI: 10.1016/j.transproceed.2012.03.033
[30] Wilson CH, Rix DA, Manas DM. Routine intraoperative ureteric stenting for kidney transplant recipients. Cochrane Database Syst Rev. 2013 Jun 17;(6):CD004925. DOI: 10.1002/14651858.CD004925.pub3
[31] Hugosson J, Grenabo L, Hedelin H, Lincolon K, Pettersson S. Chronic urinary tract infection and renal stones. Scand J Urol Nephrol. 1989;23(1):61-6.
[32] Mira Moreno A, Montoya Lirola MD, García Tabar PJ, Galiano Baena JF, Tenza Tenza JA, Lobato Encinas JJ. Incidence of infectious complications after extracorporeal shock wave lithotripsy in patients without associated risk factors. J Urol. 2014 Nov;192(5):1446-9. DOI: 10.1016/j.juro.2014.05.091
[33] Honey RJ, Ordon M, Ghiculete D, Wiesenthal JD, Kodama R, Pace KT. A prospective study examining the incidence of bacteriuria and urinary tract infection after shock wave lithotripsy with targeted antibiotic prophylaxis. J Urol. 2013 Jun;189(6):2112-7. DOI: 10.1016/j.juro.2012.12.063
[34] Grabe M. Antimicrobial Agents in Transurethral Prostatic Resection. J Urol. 1987 Aug;138(2):245–52. DOI: 10.1016/S0022-5347(17)43109-0
[35] Grabe M, Forsgren A, Hellsten S. The effect of a short antibiotic course in transurethral prostatic resection. Scand J Urol Nephrol. 1984;18(1):37-42.
[36] Rao PN, Dube DA, Weightman NC, Oppenheim BA, Morris J. Prediction of Septicemia Following Endourological Manipulation for Stones in the Upper Urinary Tract. J Urol. 1991 Oct;146(4):955–60. DOI: 10.1016/S0022-5347(17)37974-0
[37] Herr HW. Outpatient urological procedures in antibiotic-naive patients with bladder cancer with asymptomatic bacteriuria. BJU Int. 2012 Dec;110(11 Pt B):E658-60. DOI: 10.1111/j.1464-410X.2012.11405.x
[38] Cafferkey MT, Falkiner FR, Gillespie WA, Murphy DM. Antibiotics for the prevention of septicaemia in urology. J Antimicrob Chemother. 1982 Jun;9(6):471-7.
[39] Allan WR, Kumar A. Prophylactic mezlocillin for transurethral prostatectomy. Br J Urol. 1985 Feb;57(1):46-9.
[40] Cordero-Ampuero J, González-Fernández E, Martínez-Vélez D, Esteban J. Are antibiotics necessary in hip arthroplasty with asymptomatic bacteriuria? Seeding risk with/without treatment. Clin Orthop Relat Res. 2013 Dec;471(12):3822-9. DOI: 10.1007/s11999-013-2868-z
[41] Martínez-Vélez D, González-Fernández E, Esteban J, Cordero-Ampuero J. Prevalence of asymptomatic bacteriuria in knee arthroplasty patients and subsequent risk of prosthesis infection. Eur J Orthop Surg Traumatol. 2016 Feb;26(2):209-14. DOI: 10.1007/s00590-015-1720-4
[42] Gołębiewska J, Dębska-Ślizień A, Komarnicka J, Samet A, Rutkowski B. Urinary tract infections in renal transplant recipients. Transplant Proc. 2011 Oct;43(8):2985-90. DOI: 10.1016/j.transproceed.2011.07.010
[43] Green H, Rahamimov R, Goldberg E, Leibovici L, Gafter U, Bishara J, Mor E, Paul M. Consequences of treated versus untreated asymptomatic bacteriuria in the first year following kidney transplantation: retrospective observational study. Eur J Clin Microbiol Infect Dis. 2013 Jan;32(1):127-31. DOI: 10.1007/s10096-012-1727-2
[44] Origüen J, López-Medrano F, Fernández-Ruiz M, Polanco N, Gutiérrez E, González E, Mérida E, Ruiz-Merlo T, Morales-Cartagena A, Pérez-Jacoiste Asín MA, García-Reyne A, San Juan R, Orellana MÁ, Andrés A, Aguado JM. Should Asymptomatic Bacteriuria Be Systematically Treated in Kidney Transplant Recipients? Results From a Randomized Controlled Trial. Am J Transplant. 2016 Oct;16(10):2943-2953. DOI: 10.1111/ajt.13829
[45] Waites KB, Canupp KC, DeVivo MJ. Epidemiology and risk factors for urinary tract infection following spinal cord injury. Arch Phys Med Rehabil. 1993 Jul;74(7):691-5. DOI: 10.1016/0003-9993(93)90026-7
[46] Svanborg C, Godaly G. Bacterial virulence in urinary tract infection. Infect Dis Clin North Am. 1997 Sep;11(3):513-29. DOI: 10.1016/S0891-5520(05)70371-8
[47] Mohler JL, Cowen DL, Flanigan RC. Suppression and treatment of urinary tract infection in patients with an intermittently catheterized neurogenic bladder. J Urol. 1987 Aug;138(2):336-40. DOI: 10.1016/S0022-5347(17)43138-7
[48] Maynard FM, Diokno AC. Urinary infection and complications during clean intermittent catheterization following spinal cord injury. J Urol. 1984 Nov;132(5):943-6. DOI: 10.1016/S0022-5347(17)49959-9
[49] Lavado EL, Cardoso JR, Silva LG, Dela Bela LF, Atallah AN. Effectiveness of aerobic physical training for treatment of chronic asymptomatic bacteriuria in subjects with spinal cord injury: a randomized controlled trial. Clin Rehabil. 2013 Feb;27(2):142-9. DOI: 10.1177/0269215512450522

The ZB MED – Information Center for Life Sciences, Germany, together with the European Association of Urology (EAU) provided the opportunity to publish a “Living Textbook” on “Urogenital Infections and Inflammations” in an open access form. This “Living Textbook” represents also an update of the Textbook on Urogenital Infections published 2010 by the International Consultation on Urological Infections and the EAU: http://www.icud.info/urogenitalinfections.html.

The “Living Textbook” will cover infections and inflammations of the kidney, the urinary tract, as well as the male and female genital tract considering pathogenesis, diagnostics, treatment, prophylaxis and future aspects. The “Living Textbook” will be structured into about 26 Sections each with two section co-chairs responsible for peer review of the chapters of each section. Each chapter should reflect the background to the topic and highlight all of the critical evidence relating to the subject. The intention is to provide an up to date, concise synthesis of the literature on that topic, and for clinical topics also recommendations based on levels of evidence for contemporary clinical practice, as well as suggested research recommendations.

The editors hope that this “Living Textbook” may become a useful instrument for physicians of different specialties taking care about patients suffering from these diseases.

Truls E. Bjerklund Johansen (Norway),

Florian ME Wagenlehner (Germany),

Yong-Hyun Cho (South Korea),

Tetsuro Matsumoto (Japan),

John N Krieger (USA),

Daniel Shoskes (USA),

Kurt G. Naber (Germany).

Publishing at PUBLISSO

Your chapter will be published at the PUBLISSO platform (https://books.publisso.de).

Information for corresponding authors

It is necessary for all corresponding authors to register at PUBLISSO.
To register at PUBLISSO please click the following link: http://books.publisso.de/publisso_gold/register

After registration, please complete your user profile. Information from your user profile will appear in the published chapter and the authors board of the book (http://books.publisso.de/publisso_gold/book/52). If you are displayed in the authors board, you can be contacted by readers and other professionals. You can also contact other authors of the book for exchange and to build a network.
(If you do not want to be displayed in the authors board, but stay registered, you can disable this feature in your profile settings. In this case, your affiliation (publication data) will be displayed in the published chapter only.)

We kindly ask you to provide the co-authors email addresses in the manuscript so that we can contact them in case of queries.

Information for co-authors

After publication of your chapter, your affiliation (publication data) will be displayed in the published chapter.

If you also want to be displayed in the authors board of the book (http://books.publisso.de/publisso_gold/book/52), we kindly ask you to register at PUBLISSO. If you are displayed in the authors board, you can be contacted by readers and other professionals. You can also contact other authors of the book for exchange and to build a network.

To register at PUBLISSO please click the following link: http://books.publisso.de/publisso_gold/register

If you do not want to be displayed in the authors board of the book, you do not have to register. Your affiliation (publication data) will be displayed in the published chapter only.


If you have any further questions please don’t hesitate to contact the PUBLISSO editorial office:

E-Mail: livingbooks@zbmed.de
Phone: +49 221 478-7093


The textbook will be structured in sections with two co-chairs each. Each section will start with an introductory chapter written by the two respective co-chairs presented like an editorial commentary in regard to the following chapters (see proposed contents of the book). The two co-chairs of each section will also peer review all chapters in their section and stimulate a consensus discussion within their section together with the authors and the main editors if needed.


Each chapter should reflect the background to the topic and highlight all of the critical evidence relating to the subject. The intention is to provide an up to date, concise synthesis of the literature on that topic, and for clinical topics also recommendations based on levels of evidence for contemporary clinical practice, as well as suggested research recommendations.


Each manuscript should have up to approximately 3,000 words (excluding abstract, tables/figures and references). The abstract should count about 300 words.


The outline of each chapter should be structured as follows (similar as in the edition 2010, which can be downloaded for free: http://www.icud.info/urogenitalinfections.html):

  1. Abstract
  2. Summary of recommendations*/key notes*
    (*which ever term is more appropriate)
  3. Introduction
  4. Methods
  5. Results
  6. Further research
  7. Conclusions
  8. Acknowledgement
  9. Conflict of interest of each author
  10. References

Citation style

As a citation style, the Vancouver style is preferred.

Please mark your references in the text with square brackets ([1], [2], ...).

Summary of recommendations

We would like to have the Summary of recommendations at the beginning after the abstract (as in the edition 2010). However, we do not expect as in the edition 2010, that each recommendation is also specified according to Level of Evidence and Grade of Recommendation, because such a claim would not only need a systematic literature search (see below), but also a structured discussion in a defined group of experts.

Systematic literature search

A systematic literature search should be performed, at least of PUBMED/MEDLINE but ideally of several relevant databases in addition (like Cochrane CENTRAL) to find recent, high quality systematic reviews and/or primary research studies. It is not expected to perform for all chapters a de novo systematic review, if such reviews are already published recently, but it still may be indicated for some items. For questions relating therapy, it should be focused on evidence from (systematic reviews of) randomized controlled trials if available.

The method of the systematic literature search needs to be fully described in the section “Methods”, e.g.:

“A systematic literature search was performed for the last ... (usually 10) years in MEDLINE, Cochrane etc. with the following key words ... and the following limitations: e.g. UTI, age (adult?), ... clinical studies ... English ... abstract available ... only peer reviewed ...

A total of ... publications were identified, which were screened by title and abstract ... After exclusion of duplicates ... a total of ... were included into the review (analysis), supplemented by citations or known to the authors ... ”.

Clinical topics

Clinical topics should be focused on the importance to clinical practice according to the up to date scientific knowledge as presented in the literature. It should relate to questions/complaints/symptoms of patient/population concerning definition, diagnosis, therapy/prevention, intervention, and outcome in comparison, if different approaches are feasible. Please choose patient-important outcomes and focus on those, which you deem critical for decision-making.

Level of evidence and grade of recommendations

Any recommendation should be based on the level of evidence and the grade of recommendation. For this purpose the following system, modified from the Oxford Centre for Evidence-based Medicine should be used (EAU guidelines 2015):

Level of evidence (LE)

Level Type of evidence
1a Evidence obtained from meta-analysis of randomised trials
1b Evidence obtained from at least one randomised trial
2a Evidence obtained from one well-designed controlled study without randomization
2b Evidence obtained from at least one other type of well-designed quasi-experimental study
3 Evidence obtained from well-designed non-experimental studies, such as comparative studies, correlation studies and case reports.
4 Evidence obtained from expert committee reports or opinions or clinical experience of respected authorities.

Grade of Recommendations (GoR)

Grade Nature of recommendations
A Based on clinical studies of good quality and consistency addressing the specific recommendations and including at least one randomised trial
B Based on well-conducted clinical studies, but without randomised clinical trials
C Made despite the absence of directly applicable clinical studies of good quality

Comments (EAU guidelines 2015)

The aim of assigning a LE and grading recommendations is to provide transparency between the underlying evidence and the recommendation given.

It should be noted that when recommendations are graded, the link between the level of evidence and grade of recommendation is not directly linear. Availability of randomized controlled trials may not necessarily translate into a grade “A” recommendation where there are methodological limitations or disparity in published results.

Alternatively, absence of high level evidence does not necessarily preclude a grade A recommendation, if there is overwhelming clinical experience and consensus. In addition, there may be exceptional situations where corroborating studies cannot be performed, perhaps for ethical or other reasons and in this case unequivocal recommendations are considered helpful for the reader. The quality of the underlying scientific evidence - although a very important factor – has to be balanced against benefits and burdens, values and preferences and costs when a grade is assigned.

Since the same rating system should be used in all chapters, for the sake of brevity the same sentence could be used in “Methods” for all manuscripts, because the rating system will be described in details in the Preface of the book:

“The studies were rated according to the level of evidence and the strength of recommendations graded according to a system used in the EAU guidelines modified from the Oxford Centre for Evidence-based Medicine [1].”


[1] European Association of Urology. Guidelines. Methodology section. 2015 ed. Arnhem: European Association of Urology; 2015. p. 3. ISBN/EAN: 978-90-79754-80-9. Available from: http://uroweb.org/wp-content/uploads/EAU-Extended-Guidelines-2015-Edn..pdf

The Living Handbook of Urogenital Infections and Inflammations is issued by:

European Association of Urology
att. Maurice Schlief, EAU executive manager business affairs

P.O.Box 30016
NL-6803 AA Arnhem, The Netherlands

Phone: 0031-26-38.90.680
E-mail: m.schlief@uroweb.org

Editor in Chief

responsible for the contents according to § 5 TMG and § 55 Abs. 2 RStV (Germany):

Kurt G. Naber, MD, PhD
Assoc. Professor of Urology

Technical University of Munich
Karl-Bickleder-Str. 44c
94315 Straubing, Germany

E-mail: kurt.naber@nabers.de

John N. Krieger MD, PhD

University of Washington Section of Urology


Daniel Shoskes MD, PhD

Cleveland Clinic Glickman Urological and Kidney Institute


Yong-Hyun Cho MD, PhD

St. Mary's Hospital, The Catholic University of Korea Department of Urology


Tetsuro Matsumoto MD, PhD

University of Occupational and Environmental Health Department of Urology


Florian M. E. Wagenlehner MD, PhD

Justus-Liebig University of Giessen Clinic of Urology and Andrology


Truls Erik Bjerklund Johansen MD, PhD

Oslo University Hospital Urology Department


Kurt G. Naber MD, PhD

Technical University of Munich


Punit Bansal MD, PhD

R G Stone and Super Specialty Hospital
Department of Urology


Riccardo Bartoletti

University of Pisa
Department of Translational Research and New Technologies


Truls Erik Bjerklund Johansen MD, PhD

Oslo University Hospital
Urology Department


PD Dr. med. Gernot Bonkat

University Basel
alta uro AG, Merian Iselin Klinik, Center of Biomechanics & Calorimetry (COB)


Prof. Tommaso Cai MD

Santa Chiara Regional Hospital
Dept. of Urology


Dr Leyland Chuang

Ng Teng Fong Hospital, National University Health System
Department of Medicine


Prof. Milan Cizman

University Medical Centre
Department of Infectious Diseases


Alison Crawford MSc

Queen's University
Department of Psychology


Pfofessor Svetlana Dubrovina MD, PhD

Rostov Medical State University
Obstetrics and Gynaecology


Dr Valerie Huei Li Gan MBBS (S'pore), MRCS (Edin), MMed (Surg), FAMS (Urology)

Singapore General Hospital
Department of Urology


Philip Hanno

University of Pennsylvania


Ass prof MD Gundela Holmdahl

Queen Silvia Childrens Hospital, Sahlgrens Academy
Pediatric surgery and urology


Udo B. Hoyme

HELIOS Hospital Erfurt Ltd.
Department of Gynecology and Obstetrics


David Hunstad

Washington University School of Medicine
Pediatrics / Molecular Microbiology


Gitte M. Hvistendahl

Aarhus University Hospital


Prof. Michael KOGAN M.D., PhD

Rostov State Medical University
Department of Urology


Dr Akihiro Kanematsu

Hyogo College of Medicine
Department of Urology


Frieder Keller

University Hospital Ulm
Department Internal Medicine 1, Nephrology


Professor Katarzyna Kilis-Pstrusinska PhD, MD

Wroclaw Medical University
Department of Pediatric Nephrology


MD, PhD Tae-Hyoung Kim

Chung-Ang University


John N. Krieger MD, PhD

University of Washington
Section of Urology


Prof Ekaterina Kulchavenya

Novosibirsk Research TB Institute, Novosibirsk State Medical University


Dr Christina Kåbjörn Gustafsson

Ryhov Hospital Jönköping


Dr. Bela Köves

South Pest Teaching Hospital
Department of Urology


Iara Linhares

Dr. med. Giuseppe Magistro

Ludwig-Maximilians-University of Munich
Department of Urology


Vittorio Magri

Urologic Clinic


András Magyar

South-Pest Hospital
Department of Urology


Professor Emeritus Brian Morris

University of Sydney
School of Medical Sciences


Baerbel Muendner-Hensen

ICA-Deutschland e.V.


Stephen F. Murphy

Feinberg School of Medicine, Northwestern University
Department of Urology


Kurt G. Naber MD, PhD

Technical University of Munich


Prof. Yulia Naboka

Rostov State Medical University
Department of Microbiology


Dr. J. Curtis Nickel MD

Queen's University
Department of Urology


Professor Ralph Peeker MD PhD

University of Gothenburg
Department of Urology


Tamara Perepanova

N.A. Lopatkin Research Institute of Urology and Interventional Radiology


Prof. Gianpaolo Perletti M. Clin. Pharmacol.

University of Insubria
Department of Biotechnology and Life Sciences


Felice Petraglia

Department of Biomedical, Experimental and Clinical Sciences, University of Florence
Obstetrics and Gynecology


Michel Pontari

Temple University School of Medicine
Department of Urology


Dr. Jörgen Quaghebeur PhD. Med. Sci.

University Hospital Antwerp and University Antwerp
Department of Urology


Yazan F. Rawashdeh

Aarhus University Hospital
Paediatric Urology Section, Department of Urology


Professor Claus Riedl MD



Matthew Roberts

The University of Queensland
Faculty of Medicine


PD Dr. med Guido Schmiemann MPH

Institut für Public Health und Pflegeforschung, Universität Bremen
Abteilung Versorgungsforschung


Caroline Schneeberger MD PhD

Academic Medical Center (AMC)


Prof. Dr. med. Peter Schneede

Klinikum Memmingen
Department of Urology


Aaron C. Shoskes

Des Moines University Medical College of Ostheopathic Medicine


Daniel Shoskes MD, PhD

Cleveland Clinic
Glickman Urological and Kidney Institute


Prof. Dr. Roswitha Siener

University of Bonn
University Stone Centre, Department of Urology


Sofia Sjöström

Queen Silvia Childrens Hospital, Sahlgrens Academy
Pediatric surgery and urology


Mathew Sorensen

University of Washington School of Medicine
Department of Urology


Prof. Dr. Dr. Walter Ludwig Strohmaier FEBU

Regiomed-Klinikum Coburg. Medical School Regiomed
Urology and Paediatric Urology


Satoshi Takahashi

Sapporo Medical University School of Medicine
Department of Infection Control and Laboratory Medicine


Professor Paul Anantharajah Tambyah

Yong Loo Lin School of Medicine, National University Hospital
Department of Medicine


Peter Tenke

Jahn Ferenc South Pest Teaching Hospital
Department of Urology


Praveen Thumbikat

Department of Urology


Dr. Jose Tiran Saucedo

IMIGO / Universidad de Monterrey
Obstetrics and Gynaecology


Dominic Tran-Nguyen

Des Moines University


Dean Tripp

Queen's University
Psychology, Anesthesia & Urology



The Catholic University of Korea, St. Vincent's Hospital
Division of Infectious Diseases, Department of Internal Medicine


Florian M. E. Wagenlehner MD, PhD

Justus-Liebig University of Giessen
Clinic of Urology and Andrology


Assoc. Prof. Christian Wejse

Aarhus University, Aarhus University Hospital
Department of Infectious Diseases/Center for Global Health, Dept of Public Health


Prof. Dr. Mete Çek

Trakya University, School of Medicine