Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults

Urinary tract infections in patients with diabetes mellitus: epidemiology, pathogenesis and treatment

Patients with diabetes mellitus (DM) have a higher prevalence of asymptomatic bacteriuria (ASB) and incidence of urinary tract infections (UTIs) compared with patients without DM. They also more often have bacteraemia, with the urinary tract as the most common focus for these infections, as well as a higher mortality outside the hospital compared with patients without DM. It appears that the increased prevalence of ASB in diabetic women is not the result of a difference in causative bacteria, as the same virulence factors and resistance to antimicrobials were found in Escherichia coli isolated from the urine of diabetic women with ASB compared with non-diabetic controls. Bacterial growth in vitro is increased after the addition of glucose, however glucosuria is not a risk factor for ASB or for the development of UTIs in vivo. No differences in granulocyte function tests were demonstrated among diabetic women with ASB, non-bacteriuric women and healthy control subjects, but women with both ASB and DM had lower urinary cytokine and leukocyte concentrations than women with ASB without DM. Finally, it was found that E. coli expressing type 1 fimbriae adhere better to uroepithelial cells of women with DM compared with those isolated from women without DM. There are no randomised trials that answer the question as to the optimal duration of treatment for UTIs in diabetic patients. It has been recommended to consider these patients as having a complicated UTI and therefore to treat them for a period of 7-14 days.

Pregnancy in renal transplant recipients

Women with renal disease face increasing infertility and high-risk pregnancy as they approach end-stage renal disease due to uremia. Renal transplantation has provided these patients the ability to return to a better quality of life, and for a number of women who are of child bearing age with renal disease, it has restored their fertility and provided the opportunity to have children. But, although fertility is restored, pregnancy in these women still harbors risk to the mother, graft, and fetus. Selected patients who have stable graft function can have successful pregnancies under the supervision of a multidisciplinary team involving maternal fetal medicine specialists and transplant nephrologists. Careful observation and management are required to optimize outcome for mother and fetus.

Short-term therapy for urinary tract infection: success and failure

The pharmacokinetic characteristics of some antimicrobials lead to very high urinary concentrations. This, together with the superficial nature of bladder infection and effective voiding, supports the use of short-course antimicrobial therapy for treatment of acute uncomplicated cystitis. Even a single dose is effective for >90% of episodes for some antimicrobials. Short-course therapy for 3 days is, however, the current accepted standard of therapy for acute uncomplicated urinary tract infection (UTI). Complicated UTI is a more diverse clinical entity. For individuals with some underlying abnormalities, including incomplete drainage of urine or renal failure, short-course therapy is never appropriate. However, some individuals with complicated UTI have adequate urinary emptying, infection limited to the bladder and normal renal function. For these persons, the same principles that promote effective short-course therapy for treatment of acute uncomplicated UTI should also apply. However, clinical studies reported to date do not support the use of short-course therapy for treatment of complicated cystitis. Further studies enrolling well-characterised patient populations with consistent clinical presentations are required to define the role, if any, of short-course therapy in complicated UTI.

Best practice in primary care pathology: review 10

This tenth best practice review examines four series of common primary care questions in laboratory medicine: (i) antenatal testing in pregnant women; (ii) estimated glomerular filtration rate calculation; (iii) safety testing for methotrexate; and (iv) blood glucose measurement in diabetes. The review is presented in question-answer format, referenced for each question series. The recommendations represent a precis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by Medline Embase searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence-based. They will be updated periodically to take account of new information.

Asymptomatic bacteriuria and urinary tract infection in older adults

Asymptomatic bacteriuria (ASB) and urinary tract infection (UTI) are common in older community dwellers (ages 65 and older) and nursing home residents. The challenge involved in distinguishing ASB from UTI in this population results from other comorbid illnesses that may present with symptoms similar to UTI and from elderly adults who have cognitive impairment not being able to report their symptoms. This article reviews the most updated information on diagnosis, microbiology, management, and prevention of ASB and UTI as they pertain to older community dwellers and nursing home residents.

Incidence et caractéristiques cliniques des infections urinaires symptomatiques dans un hôpital gériatrique

OBJECTIVES AND SETTINGS: The authors had for aim to study the incidence of symptomatic urinary infections (SUTI) in elderly patients, to describe their clinical and microbiologic characteristics and first-line treatment in a geriatric hospital with 902 beds: 124 in acute care (ACF), 293 in rehabilitation and intermediate-care (RICF), and 485 in long-term-care-facilities (LTCF).

METHOD

During two months in 2003, all positive urine cultures detected by the laboratory were sent to the clinician with a questionnaire on clinical signs, diagnosis of SUTI and antibiotic treatment.

RESULTS

SUTI was diagnosed in 85 out of 204 positive urine cultures (40%). The incidence of SUTI was 1.86 per 1,000 patient-days (with rates of 2.63, 2.49, 1.41 per 1,000 patients-days for the ACF, RICF, LTCF respectively). For 51 cases (60%) there were only general symptoms, for 24 cases (28.2%) there were only urinary symptoms, and for 10 cases (11.8%) there were both. Escherichia coli and Proteus mirabilis were the main bacterial species involved in 57 and 14% respectively. E. coli strains were 59% resistant to amoxicillin, 55% resistant to amoxicillin-clavulanic acid, and 39% resistant to fluoroquinolones. The main antibiotics were fluoroquinolones, ceftriaxone, and amoxicillin-clavulanate, prescribed respectively in 52.5, 19, and 9% of the cases.

CONCLUSION

SUTI was diagnosed in only in 40% of positive urine cultures from elderly patients hospitalized in our hospital. To improve the management of SUTI in this population, we changed our recommendations for diagnosis and treatment.

Infections in Diabetes Mellitus and Hyperglycemia

Infections in diabetes mellitus are relatively more common and serious. Diabetic patients run the risk of acute metabolic decompensation during infections, and conversely patients with metabolic decompensation are at higher risk of certain invasive infections. Tight glycemic control is of paramount importance during acute infected or high stress state. Infections in diabetic patients result in extended hospital stays and additional financial burden. Given the risks of not alleviating the metabolic dysregulation and the benefits of decent glycemic control, it is necessary that besides antimicrobial therapy, equal emphasis be placed on intensified glycemic control.

Neurogenic bladder in spinal cord injury

In the past, renal failure was the leading cause of death after spinal cord injury (SCI). Today mortality from SCI has declined dramatically partly owing to the improved management of urologic dysfunction associated with SCI. The goals of bladder management in spinal cord injury patients are intended to (1) ensure social continence for reintegration into community, (2) allow low-pressure storage and efficient bladder emptying at low detrusor pressures, (3) avoid stretch injury from repeated overdistension, (4) prevent upper and lower urinary tracts complications from high intravesical pressures, and (5) prevent recurrent urinary tract infections. This article provides an overview of neurogenic bladder dysfunction associated with SCI and current management options.

Infections in the elderly

Infectious diseases remain a significant cause of morbidity and mortality in the growing number of adults over the age of 65 years in the United States. Declining immunity coupled with aging anatomy and physiology set the stage for increased vulnerability to infections and the development of atypical presentations in the elderly. Pneumonia, urinary tract infection, and skin and soft tissue infections are illnesses commonly encountered in the care of this unique population. This article explores the etiology, diagnosis, and constantly evolving treatment of these conditions in the context of the elderly patient.

[Nosocomial urinary tract infection in adults]

Urinary tract infection (UTI) is the most common infection in hospitalized adults. Nosocomial UTIs are mainly associated with the use of urinary catheters. Thus, the decision for catheterization should be made carefully and catheters removed in time. In order to prevent unnecessary antibiotic use in patients with urinary catheters correct diagnosis is crucial. Chinolones, broad-spectrum penicillins and third-generation cephalosporins are the mainstay of therapy. Comorbidities should be considered and potential obstructions of urinary flow removed. Economically important are the normally higher prices of i.v. antibiotics compared to oral use.

A randomized trial of catheter change and short course of antibiotics for asymptomatic bacteriuria in catheterized ICU patients

OBJECTIVE

To determine the effect on the occurrence of urosepsis of a treatment with a short course of antibiotics and indwelling urethral catheter replacement in clinically asymptomatic intensive care unit (ICU) patients with a positive urine culture occurring at least 48 h after catheterization.

METHODS

A prospective randomized clinical trial was conducted in the medico-surgical ICU of a tertiary care centre. Sixty patients hospitalized in the ICU with an indwelling urethral catheter for longer than 48 h developing an asymptomatic positive urine culture were randomized to receive either a 3-day course of antibiotics associated with the replacement of the indwelling urethral catheter 4 h after first antibiotic administration or no antibiotics, no catheter replacement (standard of care).

RESULTS

Three patients in each group developed urosepsis (P=0.1). There were no significant differences in duration of mechanical ventilation between the study group and the standard of care group (9 [4-20] days vs 5 [2-15] days, P=0.2), in duration of urinary catheterization (22 [11-40] days vs 18 [14-33] days, P=0.8), or in length of ICU stay (28 [13-46] vs 19 [15-34], P=0.6). The recurrence of positive urine culture at days 7 and 15 was not affected by the randomization (P=0.1). The profile of bacterial resistance was similar in the two groups.

CONCLUSIONS

Treating a positive urine culture in an asymptomatic patient with an indwelling urethral catheter does not reduce the occurrence of urosepsis in the medico-surgical ICU.

Common infections in diabetes: pathogenesis, management and relationship to glycaemic control

Specific defects in innate and adaptive immune function have been identified in diabetic patients in a range of in vitro studies. However, the relevance of these findings to the integrated response to infection in vivo remains unclear, especially in patients with good glycaemic control. Vaccine efficacy seems adequate in most diabetic patients, but those with type 1 diabetes and high glycosylated haemoglobin levels are most likely to exhibit hypo-responsiveness. While particular infections are closely associated with diabetes, this is usually in the context of extreme metabolic disturbances such as ketoacidosis. The link between glycaemic control and the risk of common community-acquired infections is less well established but could be clarified if infection data from large community-based observational or intervention studies were available. The relationship between hospital-acquired infections and diabetes is well recognized, particularly among post-operative cardiac and critically ill surgical patients in whom intensive insulin therapy improves clinical outcome independent of glycaemia. Nevertheless, further research is needed to improve our understanding of the role of diabetes and glycaemic control in the pathogenesis and management of community- and hospital-acquired infections.

Coating urinary catheters with an avirulent strain of Escherichia coli as a means to establish asymptomatic colonization

We investigated whether insertion of urinary catheters that had been coated with Escherichia coli HU2117 could establish bladder colonization with this nonvirulent organism. Ten of 12 subjects were successfully colonized for 14 days or more. The rate of symptomatic UTI during colonization was 0.15 per 100 patient-days.

Contributions of molecular epidemiology to the understanding of infectious disease transmission, pathogenesis, and evolution

PURPOSE

Describe the contributions of molecular genetics to our understanding of the molecular epidemiology of infectious diseases caused by bacteria.

METHODS

Synthesize the literature, highlighting work on Escherichia coli and Group B streptococcus.

RESULTS

1) Commensal bacteria are genetically and phenotypically diverse. 2) Disease-causing strains of commensal bacteria often have special characteristics than allow them to be distinguished from common inhabitants. 3) Colonization by commensal bacteria is dynamic. 4) Commensal bacteria are transmitted between individuals.

CONCLUSIONS

Applications of epidemiologic principles to bacterial populations gives insight into the natural history of colonization and transmission in the human host.

Clinical study of complicated urinary tract infection using 'The UTI Criteria (Draft Fourth Edition)': measurement methods for pyuria

OBJECTIVE

To evaluate the influences the change of the measurement method of pyuria from conventional centrifuged sediment to microchamber uncentrifuged urine for the results of evaluation of antimicrobial agents in clinical study against complicated urinary tract infections. From the viewpoint of international harmonization of judgement criteria, the recent method for counting white blood cells (WBC) in urine has changed from using uncentrifuged urine to using a microchamber in all countries.

METHODS

Targeted diseases were non-catheterized complicated urinary tract infection, and cefcapene pivoxil hydrochloride or levofloxacin were used as antimicrobial drug. Pyuria was examined using the counting chamber method, a quantitative method using uncentrifuged urine with a microchamber, and the sedimentation method.

RESULTS

Overall clinical efficacy in early evaluation by the two methods in measuring pyuria was evaluated as different in eight patients (7.3%). It was rated excellent in 63 (52.9%), moderate in 32 patients (26.9%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the counting chamber method, and excellent in 68 (57.1%), moderate in 27 (22.7%) and poor in 24 (20.2%) with an efficacy rate of 79.8% using the conventional sedimentation method

CONCLUSION

No significant difference was seen between the two methods of WBC count in urine.

Renal allograft injury is associated with urinary tract infection caused by Escherichia coli bearing adherence factors

Urinary tract infections are the most common infection in renal transplant patients and Escherichia coli (E. coli) is the most common clinical isolate. Although acute allograft injury (AAI) secondary to urinary tract infection (UTI) has been reported, the incidence of AAI associated with UTI, the virulence factors express by uropathic E. coli and whether virulence factors are associated with renal allograft outcome have not been described. We collected E. coli from our renal transplant patients with UTI, determined O:H serotypes, P and Dr fimbriae expression and the clinical presentation and allograft function during the UTI and post-UTI period. Pyelonephritis occurred in 40% of our patients, 82% of which had AAI (>20% increase in SCr). Sixty-two percent of E. coli isolates that expressed P fimbriae were associated with AAI, whereas only 29% that did not express P fimbriae had AAI (p = 0.03). The pattern of P fimbriae and O serotypes differed from reported isolates, as the P fimbriae PapG class II and the O25 serotype were the most common. Dr adhesin was expressed on 7 isolates, including 2 of 3 with urosepsis. We propose a unique pattern of uropathogenic serotypes and adherence factors contribute to acute allograft injury in renal transplant patients with UTI.

[Recurrent urinary tract infections]

Recurrent urinary tract infections (RUTI) are a frequent clinical problem in sexually active young women, pregnant or postmenopausal women and in patients with underlying urological abnormalities. The present chapter reviews RUTI based on their classification: relapses, which usually occur early (< 1 month), are caused by the same microorganism and are associated with underlying urological abnormalities, and reinfections, which usually occur later and are caused by a new distinct microorganism (or by the same microorganism usually located in the rectum or uroepithelial cells). The pathogenesis of RUTI is reviewed and the risk factors associated with RUTI in premenopausal women (usually related to sexual activity), postmenopausal women (in whom estrogen deficiency has a significant effect on the vaginal Lactobacillus flora), and in pregnant women are discussed. Likewise, an extensive review of the distinct therapeutic strategies to prevent RUTI is provided: self-treatment of cystitis, continuous antibiotic prophylaxis, postcoital antibiotic prophylaxis, topical vaginal estrogens, Lactobacillus, cranberry juice, intravesical administration of non-virulent E. coli strains and vaccines, among others. Several diagnostic-therapeutic algorithms are included. These algorithms are based on the type of urinary infection (relapse-reinfection), on the type of patient (young, postmenopausal, or pregnant women) and on the number of episodes of RUTI.

[Urinary tract infection in pregnancy]

Urinary tract infections, asymptomatic bacteriuria (AB), acute cystitis (AC) and acute pyelonephritis (AP), are favored by the morphological and functional changes involved in pregnancy. AB increases the risk of preterm labor, low birth weight and AP. AB should be detected by uroculture (other methods are not sufficiently effective) and treated early. Approximately 80% of cases are caused by Escherichia coli. The risks and effectiveness of the distinct antibiotic regimens should be evaluated: fosfomycin trometamol in monotherapy or as short course therapy is safe and effective for the treatment of AB and AC. AP is the most frequent cause of hospital admission for medical reasons in pregnant women and can lead to complications in 10% of cases, putting the lives of the mother and fetus at risk. Currently outpatient treatment of AP is recommended in selected cases. Adequate follow-up of pregnant women with urinary tract infections is required due to frequent recurrence.

The microbiology of bacteriuria in men: a 5-year study at a Veterans' Affairs hospital

Bacteriuria and urinary tract infection occur relatively frequently in older men, but data regarding the causative microorganisms are limited. We retrospectively identified all positive cultures of urine specimens (n = 4943) obtained over a 5-year period at our institution. We determined the frequency of causative microorganisms and grouped these by Gram type, setting of patient care, and method of urine specimen collection. We also assessed the performance characteristics of the Gram-stained smear of uncentrifuged urine. Among our patients, Gram-positive cocci (GPC) were isolated as often as Gram-negative rods (GNR). Escherichia coli was the single or predominant isolate in only 14% of cases, and Enterococcus was the single most commonly identified genus (22.5%). The Gram stain was accurate in predicting the culture results (positive likelihood ratio, 7.0 for GPC and 8.1 for GNR). We conclude that the microorganisms causing bacteriuria in older male veterans are substantially different from those found in women, and the Gram-stained smear provides useful information on the causative organisms.

Is single-dose fosfomycin trometamol a good alternative for asymptomatic bacteriuria in the second trimesterof pregnancy?

Untreated asymptomatic bacteriuria has been associated with acute pyelonephritis, which may have a role in many maternal and fetal complications. Acute pyelonephritis in pregnancy is related to anemia, septicemia, transient renal dysfunction, and pulmonary insufficiency. A randomized study was conducted to assess the clinical and microbiological efficacy of a single dose of fosfomycin trometamol for the treatment of asymptomatic bacteriuria in the second trimester of pregnancy compared with a 5-day regimen of cefuroxime axetyl. Forty-four women received fosfomycin trometamol and 40 women received cefuroxime axetyl. There were no statistically significant differences between both groups regarding the mean age and mean duration of pregnancy. Therapeutic success was achieved in 93.2% of the patients treated with fosfomycin trometamol vs 95% of those treated with cefuroxime axetyl. A single dose of fosfomycin trometamol is a safe and effective alternative in the treatment of asymptomatic urinary tract infections in the second trimester of pregnancy.

Prevalence of hospital-acquired urinary tract infections in urology departments

OBJECTIVES

The aim of our study was to register the prevalence of nosocomial urinary tract infections (NAUTIs) in urology sections in Europe and Asia.

METHODS

A total of 6033 hospitalised patients in 194 different urology departments were screened in two Internet-based studies. Detailed reports on 727 patients with NAUTI were provided.

RESULTS

The prevalence of NAUTI was 10% in the Pan European Prevalence (PEP) study, 14% in the Pan EuroAsian Prevalence (PEAP) study, and 11% in the combined analysis. The largest group was asymptomatic bacteriuria (29%) followed by cystitis (26%), pyelonephritis (21%), and urosepsis (12%). There were significant differences between regions and types of hospitals.

CONCLUSIONS

NAUTI is a large problem for urologic patients and causes huge extra costs for hospitals.

Asymptomatic bacteriuria: review and discussion of the IDSA guidelines

Asymptomatic bacteriuria is a common finding, but is usually benign. Screening and treatment of asymptomatic bacteriuria is only recommended for pregnant women, or for patients prior to selected invasive genitourinary procedures. Healthy women identified with asymptomatic bacteriuria on population screening subsequently experience more frequent episodes of symptomatic infection, but antimicrobial treatment of asymptomatic bacteriuria does not decrease the occurrence of these episodes. Clinical trials in spinal-cord injury patients, diabetic women, patients with indwelling urethral catheters, and elderly nursing home residents have consistently found no benefits with treatment of asymptomatic bacteriuria. Negative outcomes with antimicrobial treatment do occur, including adverse drug effects and re-infection with organisms of increasing resistance. Optimal management of asymptomatic bacteriuria requires appropriate implementation of screening strategies to promote timely identification of the selected patients for whom treatment is beneficial, and avoidance of antimicrobial therapy where no benefit has been shown.

Urine Cytokines Profile in Renal Transplant Patients with Asymptomatic Bacteriuria

BACKGROUND

The role of asymptomatic bacteriuria in kidney transplant recipients is unknown. There is no clear evidence of its effect on transplanted kidney.

METHODS

We studied urine cytokines profile among kidney transplant recipients with bacteriuria found in screening examination. Urine cultures were collected in 269 patients with stable graft function and serum creatinine level <2 mg/dl, during their routine visits. Interleukin (IL)-6 and IL-8 levels were measured in urine samples from patients with asymptomatic bacteriuria, symptomatic urinary tract infection and patients without bacteriuria (control group). Changes in serum creatinine level in patients with asymptomatic bacteriuria and in the control group were observed during 12 months follow up.

RESULTS

Urinary tract infection (UTI) was diagnosed in five patients and asymptomatic bacteriuria in 22 patients. Urine IL-6 level was significantly higher in symptomatic UTI group (median 15.71 pg/mg) but there were no differences between group of patients with asymptomatic bacteriuria (3.92 pg/mg) and control group (2.54 pg/mg). Urine IL-8 level was higher in symptomatic UTI group (median 146.8 pg/mg) and was also significantly higher in asymptomatic bacteriuria group (33.49 pg/mg) in comparison to control group (2.97 pg/mg; P=0.0002). During 1-year follow up, incidence of UTI was higher in the asymptomatic bacteriuria group than in the control group but graft function was not different in both groups.

CONCLUSIONS

Elevated urine IL-8 level in kidney transplant patients with asymptomatic bacteriuria may reflect impaired immune response to bacterial infection and occult inflammatory process in urinary tract.

Urinary cytokine response to asymptomatic bacteriuria in type 1 diabetic children and young adults

It has been reported that urinary interleukin-6 (IL-6) and IL-8 levels are decreased in adult diabetic women with asymptomatic bacteriuria (ASB) when compared with non-diabetic women with ASB. Such impaired cytokine excretion might play a role in the higher prevalence of ASB among diabetic subjects. The aim of this study was to examine the urinary IL profile in children and young adults with type 1 diabetes mellitus (T1DM) with and without ASB. Midstream clean voiding urine samples were collected and cultured from 133 patients with T1DM (age: 15.6 +/- 5.7 yr) and 178 controls (14.1 +/- 4.7 yr) for two consecutive days. ASB was diagnosed in the case of >or=10(5) bacteria/mL. The urinary IL-6 and IL-8 concentrations were determined, and the presence of leukocyturia was also recorded. The prevalence of ASB was 16.5% in diabetic subjects and 2.8% in controls (p = 0.001). There was no difference between the diabetic and the control groups in the prevalence of 'IL-6-uria' (21.9 vs. 18.0%; p = 0.41), but IL-8 was more frequently detectable in the diabetic group (47.4 vs. 27.5%; p = 0.001). In individuals with ASB, the IL-8 level was similar in the diabetic (median: 70.0 pg/mg creatinine) and control group (42.3 pg/mg creatinine; p = 0.8). Indeed, the IL-8 levels were higher in diabetic subjects with ASB as compared with those without it (70.0 vs. <3.1 pg/mg creatinine; p = 0.001), and there was a significant association between the urinary IL-8 concentration and the bacterial count (p = 0.001). Diabetic patients with leukocyturia had higher IL-8 concentration than those without it (20.9 vs. <3.1 pg/mg creatinine; p = 0.003). Weak significant correlation was found between urinary IL-8 and hemoglobin A1c (HbA1c) (r = 0.4; p = 0.002). The sensitivity and specificity of leukocyturia were 50 and 89.9% in the whole population and those of IL-8 were 74.1 and 67.5%, respectively. In diabetic patients, 36.4% of the bacteriuria were gram-negative and 63.6% gram-positive. Our results suggest that diabetic children with ASB mount an IL-8 response to pathogens, which is comparable to non-diabetic children with bacteriuria. Thus, early in the natural history of diabetes, there are no significant changes in the IL response of children with ASB, as previously reported in adults.

Incidence and risk factors associated with urinary tract infection in diabetic patients with and without asymptomatic bacteriuria

In order to compare the incidence of symptomatic urinary tract infection (UTI) in diabetic patients with and without asymptomatic bacteriuria (ASB), and to identify other risk factors for these infections, 289 females and 168 males were studied over a 12-month period. Symptomatic UTI occurred in 69.2% of patients with ASB (67.6% female and 76.5% male) versus 9.8% without ASB (14.9% female and 2.6% male). ASB and urinary incontinence were associated with symptomatic UTI in both women and men. Other risk factors included previous antimicrobial treatment and macrovascular complications in women and obesity and prostatic syndrome in men. The presence of ASB was found to be the major risk factor for developing symptomatic urinary tract infection. Further prospective randomized clinical trials of diabetic patients with risk factors for UTI who are receiving or not receiving treatment may be considered.

[Therapy of the acute uncomplicated urinary tract infection]

Acute uncomplicated cystitis and acute uncomplicated pyelonephritis are two frequently encountered urinary tract infections (UTI) in premenopausal, healthy females. Recent epidemiological investigations showed that the incidence of these infections is higher than expected. Surveys on healthcare practices in North America revealed a high variability in the therapy of uncomplicated UTI. Standardized criteria for diagnosis and therapy of uncomplicated UTIs therefore are important in order to achieve sufficient sensitivity and specificity in clinical practice. The Infectious Diseases Society of America (IDSA) developed evidence-based guidelines for the treatment of acute uncomplicated cystitis and acute uncomplicated pyelonephritis, which were recently updated by other expert groups.

Nursing home practitioner survey of diagnostic criteria for urinary tract infections

OBJECTIVES

To identify clinical and laboratory criteria used by nursing home practitioners for diagnosis and treatment of urinary tract infections (UTIs) in nursing home residents. To determine practitioner knowledge of the most commonly used consensus criteria (i.e., McGeer criteria) for UTIs.

DESIGN

Self-administered survey.

SETTING

Three New Haven-area nursing homes.

PARTICIPANTS

Physicians (n=25), physician assistants (PAs, n=3), directors/assistant directors of nursing (n=8), charge nurses (n=37), and infection control practitioners (n=3).

MEASUREMENTS

Open- and closed-ended questions.

RESULTS

Nineteen physicians, three PAs, and 41 nurses completed 63 of 76 (83%) surveys. The five most commonly reported triggers for suspecting UTI in noncatheterized residents were change in mental status (57/63, 90%), fever (48/63, 76%), change in voiding pattern (44/63, 70%), dysuria (41/63, 65%), and change in character of urine (37/63, 59%). Asked to identify their first diagnostic step in the evaluation of UTIs, 48% (30/63) said urinary dipstick analysis, and 40% (25/63) said urinalysis and urine culture. Fourteen of 22 (64%) physicians and PAs versus 40 of 40 (100%) nurses were aware of the McGeer criteria for noncatheterized patients (P<.001); 12 of 22 (55%) physicians and PAs versus 38 of 39 (97%) nurses used them in clinical practice (P<.001).

CONCLUSION

Although surveillance and treatment consensus criteria have been developed, there are no universally accepted diagnostic criteria. This survey demonstrated a distinction between surveillance criteria and criteria practitioners used in clinical practice. Prospective data are needed to develop evidence-based clinical and laboratory criteria of UTIs in nursing home residents that can be used to identify prospectively tested treatment and prevention strategies.

Microbiological outcomes in women with diabetes and untreated asymptomatic bacteriuria

BACKGROUND

Asymptomatic bacteriuria is common in diabetic women. Treatment of asymptomatic bacteriuria is not beneficial, but the natural history of the microbiology of asymptomatic bacteriuria has not been well described.

OBJECTIVE

To describe the microbiological outcomes of bacteriuria in diabetic women with untreated asymptomatic bacteriuria.

METHODS

Study subjects were initially identified through ambulatory endocrinology clinics. They were enrolled if they had two positive urine cultures > or = 10(8) cfu/l with the same organism within 2 weeks and no symptoms referable to urinary tract infection. Women initially received a 2-week course of placebo with follow-up cultures obtained at the end of treatment and 4 weeks post-treatment. Subsequently, the prevalence of bacteriuria was determined with urine cultures obtained every 3 months to a maximum of 36 months. Outcomes at yearly intervals were designated as one of: persistent bacteriuria; spontaneous resolution; resolution with antibiotics for symptomatic urinary infection; or resolution with antibiotics given for other indications. Women with and without persistent or frequent bacteriuria were compared to identify variables associated with bacteriuria.

RESULTS

The prevalence of bacteriuria in the study cohort declined to about 50% by 9 months, and subsequently remained stable throughout 3 years follow-up. Almost 20% of subjects remained bacteriuric with the original infecting organism throughout the period of observation. With evaluation at 12-month intervals, approximately one-quarter of subjects had each of the four potential outcomes of: resolution following antibiotic therapy for symptomatic urinary infection, following antibiotic therapy for other indications, spontaneous resolution without antibiotics, and persistent bacteriuria with the same organism. Women infected with gram-negative organisms were more likely to have persistent bacteriuria. Many women with resolution of initial bacteriuria, with or without antibiotics, became bacteriuric again during follow-up.

CONCLUSIONS

Women with asymptomatic bacteriuria and diabetes tend to have persistent or recurrent asymptomatic bacteriuria. Bacteriuria is benign, and seldom permanently eradicable.

Infección urinaria asociada a catéteres urinarios en la comunidad

The prevalence of urinary catheterization in the community ranges from 0.02% to 0.07%. Despite the generalized use of closed systems, the risk of bacteriuria in patients with urethral catheters is 3%-10% per day and its presence is universal when the device remains in place for 30 days or longer. Although most of these episodes of bacteriuria are asymptomatic, up to 30% of them lead to clinical symptoms and complications, including severe sepsis and death. The microorganisms infecting the urine of catheterized patients frequently belong to species less susceptible to antibiotics and form biofilms on both the device's surfaces and probably also on the urothelium. Biofilm formation greatly hampers eradication of the involved flora by antibiotics, probably favors the development of resistance and, in some instances, constitutes the substrate on which crystal precipitates are deposited, eventually resulting in blockage of the catheter lumen. Due to the scarce number of controlled studies, there are still many gaps in our knowledge of important issues concerning the clinical management of patients with indwelling urinary catheters in the community. The present study reviews the epidemiology, risk factors, microbiology, pathogenesis, clinical manifestations, diagnosis, prevention and treatment of catheter-related urinary tract infections in the community setting.

[Risk factors for the development and persistence of asymptomatic bacteriuria in patients with type 2 diabetes]

BACKGROUND AND OBJECTIVE

To study the risk factors for the development and persistence of asymptomatic bacteriuria (AB) in type 2 diabetes mellitus (DM) patients from our health zone.

PATIENTS AND METHOD

Observational and laboratory prospective cohort study.

INCLUSION CRITERIA

women and men with type 2 DM from the 2 health centers of Petrer (Alicante).

DATA

questionnaire including particular and epidemiological data. Laboratory values: biochemistry, glycosylated hemoglobin A1C, microalbuminuria, urinary sediment and urine culture.

RESULTS

A total of 457 patients with type 2 DM were included; 63.2% women and 36.8% men. The prevalence of AB at baseline was 19.9% (25.6% in women vs 10.1% in men). 78.02% had persistence of AB after the twelve months of follow-up; 21.7% developed symptomatic urinary tract infection (UTI) and 35.2% were treated with antimicrobial agents for any reason different from UTI during the follow-up period. The persistence of AB at the end of the study was 15.5%. Female sex (p = 0.04), leukocyturia (p = 0.008), urinary incontinence (p = 0.04) and elevated C reactive protein concentration (p = 0.009) remained significant risk factors for the presence and the persistence of AB when the multivariate logistical regression analysis was done. The presence of UTI within one year before the study started (p= 0.024) and previous antibiotic treatments (p = 0.04) were also independent significant factors associated with persistent AB. 84.5% of diabetic patients with persistent AB had the same infective organism in the urine culture as those found during the initial AB.

CONCLUSIONS

In patients with type 2 diabetes, female sex, urinary incontinence, leukocyturia, and elevated C reactive protein concentration were associated with development of AB. The same occurred with obesity in women and prostatic syndrome in men. The persistence of AB with the same species of isolated microorganisms as those found in AB at study entry is frequent, but it remains to be known if eradication of pathogens is more difficult in diabetic patients or, alternatively, if AB episodes are transient.

Bacteriuria asintomática en pacientes con diabetes mellitus. ¿Tratar o no tratar?

Women with diabetes mellitus suffer symptomatic bacteriuria and symptomatic urinary infections more often than non-diabetic women. Prevalence is similar, however, in males with and without diabetes. There is a controversy on the impact of asymptomatic bacteriuria on the development of complications in diabetic patients. Current evidence is reviewed concerning the need for detection and treatment of asymptomatic bacteriuria in these patients.

Asymptomatic Bacteriuria in Elderly Patients

Asymptomatic bacteriuria (ASB) is frequent in elderly patients and even more prevalent in residents of long-term care facilities. Furthermore, because more and more people are reaching advanced age and the need for care increases with age, ASB is becoming increasingly important. There are several definitions for ASB, all of which require positive urine cultures and place little or no importance on accompanying pyuria. Most ASB is associated with complicating factors, as might be found in complicated urinary tract infections (UTIs). Thus, the bacterial spectrum associated with ASB is comparable to that seen in complicated UTIs. A variety of complicating factors are more frequently found in elderly patients with ASB, such as hormonal factors (e.g. estrogen decrease), certain anatomical factors (e.g. prostate obstruction), metabolic factors (e.g. diabetes mellitus), functional alteration of the urinary bladder, immunological changes and a high rate of indwelling-catheter use. Screening for ASB in elderly people is limited to those undergoing invasive urological procedures and surgical procedures with implant material. In other situations, examination of the urine is not recommended if signs or symptoms in the urinary tract are absent. Treatment of ASB is recommended only before urological procedures. Pyuria accompanying ASB is not an indication for antimicrobial treatment. If antimicrobial treatment is considered, concomitant factors that occur frequently in elderly people, such as renal insufficiency, must be taken into account. Although ASB is apparently a benign condition, prevention in elderly people is important. The degree of pathogenicity of bacteria causing ASB has not yet been satisfactorily elucidated. Therefore, until the implications of the bacteria involved in ASB are fully understood, implementing the same hygienic precautions as are used in individuals with symptomatic UTIs should at least be undertaken.