A 10 year survey of the antimicrobial susceptibility of urinary tract isolates in the UK: the Microbe Base project

A Clinical Perspective on the Antimicrobial Resistance Spectrum of Uropathogens in a Romanian Male Population

Considering urinary tract infections (UTIs), a significant public health problem with negligible recent research, especially on the male eastern European population, we aimed to determine the antimicrobial resistance rates of uropathogens for the most commonly used antibiotics in urological practice in our country. We conducted a multicenter retrospective study in two different teaching hospitals in Romania, analyzing urine samples from 7719 patients to determine the frequency of incriminating pathogens and their resistance to different antibiotics, in a comparative approach. We determined Escherichia coli (35.98%) to be the most common pathogen with the highest sensitivity to amikacin (S = 91.72%), meropenem (S = 97.17%) and fosfomycin (S = 86.60%) and important resistance to amoxicillin-clavulanic ac. (R = 28.03%) and levofloxacin (R = 37.69%), followed by Klebsiella spp. (22.98%) with the highest sensitivity to amikacin (S = 78.04%) and meropenem (S = 81.35%) and important resistance to amoxicillin-clavulanic ac. (R = 65.58%) and levofloxacin (R = 45.36%); the most frequent Gram-positive pathogen was Enterococcus spp. (19.73%) with the highest sensitivity for vancomycin (S = 93.75%) and fosfomycin (S = 87.5%) and considerable resistance to penicillin (R = 33.52%) and levofloxacin (R = 42.04%). The findings are an important tool in managing UTIs and should be acknowledged as reference research not only for clinicians from Romania but for all physicians treating male UTIs.

A systematic review of non-antibiotic measures for the prevention of urinary tract infections in pregnancy

Background

Urinary tract infections (UTIs) are common in pregnancy and account for the highest proportion of primary care antibiotic prescriptions issued to pregnant women in the UK. It is well known that antibiotic use is associated with increased antimicrobial resistance and therefore measures to minimise antibiotic use for UTI prevention have been studied. The efficacy and safety of these measures in pregnancy have not been addressed and therefore the aim of this study was to systematically review the literature to identify and evaluate potential measures to prevent UTIs in pregnant women.

Methods

Ten databases (EMBASE, AMED, BNI, CINAHL, Medline, PubMed, PsycINFO, Cochrane Trials, Scopus and Science Direct) were systematically searched in July 2017 for studies reporting non-antibiotic measures to prevent UTIs in pregnancy. The terms (“urinary tract infection” or UTI or bacteriuria or cystitis) AND (prevention) AND (pregnan*) were used. The quality of the publications was appraised using the Critical Appraisal Skills Programme (CASP) checklists for cohort study, case-control study and randomised controlled trial. The results were synthesised using a textual narrative approach.

Results

Search results yielded 3276 publications and after reviewing titles and removing duplicates, 57 full text articles were assessed for eligibility and eight were included in the review. Five different approaches (hygiene measures, cranberry juice, immunisation, ascorbic acid and Canephron® N) have been identified, all of which are reported to be safe in pregnancy.

Conclusion

The quality of the evidence varied considerably and only hygiene measures were supported by evidence to be recommended in practice. Future work needs to concentrate on strengthening the evidence base through improved design and reporting of studies with a focus on immunisation, ascorbic acid and Canephron® N.

Electronic supplementary material

The online version of this article (10.1186/s12884-018-1732-2) contains supplementary material, which is available to authorized users.

Uropathogen Resistance: Are Laboratory-Generated Data Reliable Enough?

Therapy of uncomplicated urinary tract infection (UTI) is based on knowledge of in vitro susceptibility profiles of uropathogens in the geographic region. Microbiological surveillance systems, which lack epidemiological and clinical data to differentiate between complicated and uncomplicated UTI may incorrectly estimate rates of resistance in the community. We determined the susceptibility profile of bacteria isolated from a random sample of 124 adult outpatients with diagnosis of uncomplicated UTI and we compared it with all outpatient urine specimens collected by the same participant laboratories during the same period. Escherichia coli was the most frequently isolated uropathogen in patients with uncomplicated UTI, and its rate of resistance to different antimicrobials was lower than overall resistance rates to E. coli reported by the participating laboratories during the same period. Resistance to cotrimoxazole was significantly lower. These results suggest that surveillance systems without clinical and epidemiological data may incorrectly gauge uropathogen resistance in the community.

Antibiotic Resistance of Uropathogens Isolated from Al-Shifa Hospital in Gaza Strip in 2002

A survey on clinical isolates from urine samples was conducted and the data obtained were analyzed to determine the most common bacterial causes of urinary tract infection in the Gaza Strip and to evaluate the sensitivity patterns to selected antimicrobials that are commonly used to treat such pathogens. Urine samples were taken for culture from inpatients and outpatients at Al-shifa hospital in Gaza. Urinary tract pathogens were identified and their susceptibility to antimicrobials was determined. Of the 4778 processed urine samples, only 1637 were recorded as positive (34%) and only 1283 were tested for antimicrobial susceptibility. Escherichia coli was the most frequent uropathogen (42%), followed by Klebsiella spp. (12.2%), Pseudomonas spp. < (10.2%), other Gram-negative bacilli (8%), b hemolytic streptococci (7.6%), Enterococcus spp. (6.9%), other Staphylococcus spp. (including S . saprophyticus) (6.5%), Proteus (4.5%), S. aureus (2.1%). Resistance to antimicrobials was extremely alarming. E. coli resistance to amoxicillin reached 97.9%, to piperacillin 78.3%, to doxycycline 90%, to sulfamethoxazole/trimethoprim 63.9% and to cefaclor 42.2%.

An increased risk of urinary tract infection precedes development of primary biliary cirrhosis

Background

Primary Biliary Cirrhosis is known to be associated with Urinary Tract Infections (UTIs), but whether these precede or follow the liver disease is unclear. We have therefore attempted to determine whether UTIs are more common in people with Primary Biliary Cirrhosis (PBC) prior to their diagnosis.

Methods

We conducted a case control study in the General Practice Research Database. All cases of PBC first recorded at least one year after entry to the dataset were selected along with up to 10 controls matched for age, sex. A second unmatched control group who had Chronic Liver Diseases but not PBC were chosen. The main exposures studied were the occurrence of Urinary tract infections and pyelonephritis at least one or at least five years before diagnosis. We also performed an analysis restricted to those younger than 55 at diagnosis, as we hypothesized the relationship to be stronger in the younger age group.

Results

PBC is associated with UTI prior to diagnosis, OR 1.50 (CI 1.26-1.78), which was similar 5 years prior to diagnosis and after adjusting for smoking. The strongest relationships were observed in pyelonephritis exposures five years before diagnosis in cases under 55 years: adjusted odds ratios were 2.60 (1.02-6.63) in comparison with matched general population controls and adjusted odds ratios were OR 2.45 (1.02-5.59) in the comparison with chronic liver disease controls.

Conclusions

We found that the association between urosepsis and PBC is specific to this disease and precedes the diagnosis of PBC in a manner not previously observed in human data. This is consistent with a causal relationship.

Perfil dos microrganismos isolados no trato urinário após sondagem vesical em cirurgia ginecológica

OBJETIVOS: determinar os microrganismosfreqüentemente encontrados nas uroculturas apóssondagem vesical e o perfil de sensibilidade aos antibióticos em mulheres submetidas a cirurgia ginecológica eletiva. MÉTODOS: estudo de corte transversal em mulheres submetidas a cirurgia ginecológica com sondagem vesical, no Instituto de Medicina Integral Professor Fernando Figueira (IMIP), em Recife, Pernambuco, Brasil, de janeiro a maio de 2007. As uroculturas foram coletadas em dois períodos: até 24h da retirada do cateter e após sete/10 dias. RESULTADOS: amostras de urina foram colhidas em 249 mulheres. Encontrouse 23,6% (n=46) de uroculturas positivas com até 24h da retirada da sonda e 11,1% (n=25) com sete/10 dias após sondagem vesical. Não foi observada diferença significativa em relação aos microrganismos, quando se compararamas duas uroculturas. A Klebsiella spp. foi o principal microrganismo em ambas uroculturas (até 24h=47,8% vs sete/10 dias=44,0%; p=0,76), seguido de Escherichia coli e outros Gram-negativos. Os antibióticos amicacina, cefepima, ciprofloxacina, meropenem e ticarcilina-clavulanato foram os que apresentaram sensibilidade igual ou superior a 75%para os principais microrganismos isolados. CONCLUSÕES: Klebsiella spp. foi o microrganismo mais encontrado nas uroculturas após sondagem vesical em cirurgias ginecológicas e o antibiótico com sensibilidade igual ou maior a 95% com via de administração oral foi a ciprofloxacina.

Antimicrobial resistance patterns of urinary tract pathogens and rationale for empirical therapy in Turkish children for the years 2000-2006

OBJECTIVE

In patients with suspected urinary tract infection (UTI), antibiotic treatment is usually started empirically, before urine culture results are available. Unfortunately, antibiotic resistance has become an increasingly pressing clinical issue in many countries. The objective of this study was to assess the changing susceptibility of urinary pathogens to commonly used antimicrobials in a six-year period to evaluate the options for empirical antibiotic therapy in children with community acquired UTI.

MATERIAL AND METHODS

A retrospective analysis of data from all pediatric urine samples processed at Fatih University Medical School microbiology laboratory was undertaken for a period of six years (January 2000-December 2006).

RESULTS

A total of 767 urinary pathogens were isolated from 767 episodes of UTI in 698 patients. The most common causative agent was Escherichia coli (E. coli) followed by Klebsiella spp. and others. In 2000 almost 60% of the E. coli isolates were susceptible to ampicillin (AMP), more than 40% to Co-trimoxazole (SXT), more than 80% to gentamicin (GN), more than 90% to cefuroxime (CXM) and amikacin (AN), and more than 60% to piperacillin (PIP). By 2006 more than 70% were resistant to AMP and more than 50% were resistant to PIP. In 2000 CIP (2.7% resistant isolates) and CXM (3.4% resistant isolates) were the most active agents against Klebsiella spp.; and none of the isolates was found to be resistant to imipenem (IMP). In 2006 GN (2.7% resistant isolates), CIP (3.5% resistant isolates), CXM (2.7% resistant isolates), and AN (8.9% resistant isolates) were the most active agents against these species and still no resistance to IMP was found. For E. Coli the increase in resistance to AMP, CTX, IMP, and PIP was statistically significant (P < 0.05). For Klebsiella spp. the increase in resistance to AMP and CXM was statistically significant (P < 0.05).

CONCLUSIONS

Empirical antibiotic selection should be based on knowledge of the local prevalence of bacterial organisms and antibiotic sensitivities, because resistance patterns may vary in different regions.

Antibiotic resistance of urinary tract pathogens and evaluation of empirical treatment in Turkish children with urinary tract infections

The changing pattern of antimicrobial resistance in the causative microorganisms of urinary tract infection (UTI) in childhood is a growing problem. The aims of this study were to assess the resistance patterns of urinary isolates to commonly used antimicrobials and to evaluate the options for empirical treatment of UTI. A prospective cross-sectional analysis of bacteria isolated from children with UTI was performed between January 2003 and January 2004. Resistance to antibiotics was analysed in three age groups: Group I, < or =12 months; Group II, 13-60 months; and Group III, >60 months. A total of 165 urinary pathogens were isolated from 131 patients. Mean patient age was 63.7+/-49.8 months. The most common causative agent was Escherichia coli (87% of cases) followed by Klebsiella pneumoniae (10%). Resistance to ampicillin (74.2%) and co-trimoxazole (61.3%) was significant in all isolates. Nitrofurantoin was the most active agent against E. coli (2.2% resistant isolates), followed by amikacin (4.9%), ceftriaxone (7.5%) and ciprofloxacin (12%). None of the isolates from Group I patients were resistant to ciprofloxacin and a low resistance rate (7.1%) was noted for amikacin. In Group II patients, none of the isolates were resistant to amikacin, and ceftriaxone was the second most suitable antibiotic (resistance rate 2.2%). In Group III patients, the lowest resistance rate was against nitrofurantoin (2.7%). In conclusion, we observed that the use of ampicillin and co-trimoxazole as a single agent for empirical treatment of a suspected UTI would not cover the majority of urinary pathogens in our region. Whilst amikacin, with a negligible resistance rate, was suitable in all age groups, gentamicin might still be useful as an empirical treatment of UTI in children aged >1 year. Nitrofurantoin could be included as a reasonable alternative in the empirical treatment of lower UTI in older children.

Urinary catheterization in care homes for older people: self-reported questionnaire audit of catheter management by care home staff

A self-administered questionnaire was used to determine care home staff's reported knowledge of the urinary catheter care standards published by the National Institute for Clinical Excellence (NICE) and the Association of Continence Care, and to see whether this differed in homes with higher catheterization rates. Seven hundred and fifty out of 1438 (52%) nursing and care staff from 37 randomly selected care homes with high, medium and low catheterization rates responded. There was no difference in reported practice in care homes in the three health districts sampled or those with differing catheterization rates. Eighty-three percent of the nursing staff and 40% of the other care staff received formal catheter care training. However, at least 10% of all staff reported not washing their hands before handling a catheter, and delaying emptying a urine bag until it was full, rather than three-quarters full. Only 45% of nursing staff and 40% of other care staff encouraged residents to empty their own catheter bags. Routine use of catheter maintenance solutions or bladder washouts was reported by 50% of all staff. Nursing staff (29%) and other care staff (54%) took urine specimens from the catheter bag tap. Compliance with standards has improved greatly since an audit in 1998. However, some non-compliance remains. There is a need for ongoing local audit and formal training in urinary catheter care, particularly for non-qualified care staff. Education is needed to ensure local implementation of NICE guidance.

Spectrum and antibiotic resistance of uropathogens isolated from hospital and community patients with urinary tract infections in two large hospitals in Kuwait

OBJECTIVES

To determine the spectrum of microbial etiology and antibiotic resistance pattern of the uropathogens that cause urinary tract infections in 2 large teaching hospitals in Kuwait over a period of 1 year.

MATERIALS AND METHODS

The Vitek identification card system was used to identify the uropathogens. Susceptibility of the isolates against 18 antibiotics was performed by the microbroth dilution method using the Vitek automated system. In addition, gram-positive bacteria were tested in parallel by the disk diffusion technique.

RESULTS

The six overall most common isolates were: Escherichia coli, accounting for 47% of isolates in both hospitals, followed by Candida spp. (10.8%), Klebsiella pneumoniae (9.6%), Streptococcus agalactiae (GBS; 9.5%), Enterococcus faecalis (4.2%) and Pseudomonas aeruginosa (4.1%). Amikacin provided the widest coverage amongst all the antibiotics tested followed by ciprofloxacin, gentamicin and piperacillin-tazobactam. For the gram-negatives, high resistance (26-63%) to the beta-lactam antibiotics was noted, especially to ampicillin, amoxicillin-clavulanic acid, cephalothin and cefuroxime. Resistance to trimethoprim-sulfamethoxazole was also high. None of the enterococci was resistant to the glycopeptides, but 38-60% of the Staphylococcus haemolyticus were resistant to vancomycin or teicoplanin.

CONCLUSION

These data show the high level of antimicrobial resistance amongst the uropathogens causing urinary tract infection in the two hospitals studied.

Fosfomycin tromethamine in uncomplicated urinary tract infections: a clinical study

The aim of our study was to verify if the empiric therapy with a single dose of 3 g fosfomycin tromethamine in patients with uncomplicated urinary tract infections (UTIs) was able to clinically resolveand to microbiologically eradicate the infection. A total of 387 out of the 400 patients (274 cases with acute and 113 cases with recurrent uncomplicated UTIs) were enrolled in the clinical study. Clinical and microbiological assessments were performed before and at 8-10 days after the administration. At follow-up high clinical recovery (88.9%) and bacteriological (94.9%) eradication rates were achieved. Gastrointestinal side effects were found in only 4.3% of patients. In conclusion, a single-dose administration regimen of fosfomycin tromethamine should be encouraged as a first choice of drug therapy for uncomplicated UTIs.

Increasing prevalence of antimicrobial resistance among Enterobacteriaceae uropathogens in Dakar, Senegal: a multicenter study

To assess antibiotic susceptibility among Enterobacteriaceae isolated in urine from outpatients in Dakar, Senegal, a prospective multicenter study involving 3 laboratories had been conducted between June and October 2001. During this period, 300 strains were isolated and susceptibility testing was performed against antibiotics commonly used in treatment of community-acquired urinary tract infections (UTI). E. coli and K. pneumoniae represented 89% of isolates. The overall resistance rates of ampicillin, amoxicillin-clavulanic acid, nalidixic acid, fluoroquinolones and cotrimoxazole were respectively 77.3%, 34.7%, 14.7%, 13.3%, and 55%. In the light of these results, a re-evaluation of first line therapies and prudent use of fluoroquinolones is advised. At the same time a continued surveillance of antimicrobial resistance should be developed in Senegal in order to control the emergence of multidrug resistant strains and to establish a national therapeutic guideline for treatment of UTI.

Bacterial susceptibility to oral antibiotics in community acquired urinary tract infection

BACKGROUND

The most common oral antibiotics used in the treatment of urinary tract infection (UTI) are sulphonamides and cephalosporins, but emerging resistance is not unusual.

AIMS

To assess the change in susceptibility of urinary pathogens to oral antibiotics during the past decade in children with community acquired UTI.

METHODS

The study sample included two groups of children with a first community acquired UTI: 142 children enrolled in 1991 and 124 enrolled in 1999. UTI was diagnosed by properly collected urine specimen (suprapubic aspiration, transurethral catheterisation, or midstream specimen in circumcised males) in symptomatic patients. Antimicrobial susceptibility of the isolates was compared between the two groups.

RESULTS

The pathogens recovered in the two groups were similar: in 1991--E coli 86%, Klebsiella 6%, others 8%; in 1999--E coli 82%, Klebsiella 13%, and others 5%. A slight but generalised decrease in bacterial susceptibility to common antibiotics in the two groups was shown: ampicillin 35% versus 30%; cephalexin 82% versus 63% (p < 0.001); nitrofurantoin 93% versus 92%. The only exception was co-trimoxazole, 60% versus 69%. Overall resistance to antibiotics in 1999 was as follows: ampicillin 70%, cephalexin 37%, co-trimoxazole 31%, amoxicillin-clavulanate 24%, nitrofurantoin 8%, cefuroxime-axetil 5%, nalidixic acid 3%.

CONCLUSIONS

This study shows a slight but generalised decrease in bacterial susceptibility to common oral antibiotics in the past decade in our population. Empirical initial treatment with co-trimoxazole or cephalexin is inadequate in approximately one third of UTI cases. A larger number of pathogens may be empirically treated with amoxicillin-clavulanate (24% resistance); 95% of organisms are susceptible to cefuroxime-axetil.

Distribution and susceptibility of bacterial urinary tract infections in Dakar, Senegal

To assess the current distribution and antibiotic susceptibility patterns of uropathogens isolated from community-acquired urinary tract infections (UTIs) in Dakar, a retrospective study was carried out at the biomedical laboratory of Institut Pasteur de Dakar between January 1999 and December 2000. The most important finding, among Enterobacteriaceae, was the emergence of multidrug resistant strains (extended-spectrum beta-lactamase and both chromosomally derepressed and plasmid mediated cephalosporinase producing strains) affecting 2.9% of all Enterobacteriaceae. Of Gram-positive cocci, 15% of Staphylococcus aureus were methicillin-resistant. Our data show the original distribution of uropathogens from UTIs in ambulant patients and the emergence of multidrug resistant strains in Dakar.

Urinary tract infection trends in Latin American hospitals: report from the SENTRY antimicrobial surveillance program (1997-2000)

Urinary tract infections (UTI) are one of the most common infectious diseases diagnosed in outpatients as well as in hospitalized patients. The objective of this study was to report the frequency of occurrence and antimicrobial susceptibility of uropathogens collected in Latin America between 1997 to 2000 through the SENTRY Antimicrobial Surveillance Program. Antimicrobial susceptibility testing was performed and results interpreted using reference broth microdilution methods. In the 4 year period, a total of 1961 urine isolates from hospitalized patients were included. The patients' mean age was 51.3 years and most of the infections occurred among women (65.6%). Esherichia coli was the most frequent pathogen isolated followed by Klebsiella spp., Pseudomonas aeruginosa, and Proteus mirabilis. Among the E. coli isolates, piperacillin/tazobactam, aztreonam, extended-spectrum cephalosporins, carbapenems and amikacin constitute reasonable therapeutic options for treatment of serious UTI in Latin America (91.0-100.0% susceptible). High resistance rates to fluoroquinolones (17.5-18.9%) and trimethoprim/sulfamethoxazole (>45.0%) were observed among the E. coli. In contrast, nitrofurantoin displayed susceptibility rate of > 87.0%. Against Klebsiella spp. infections, the only effective therapeutic option would be the carbapenems due to the high number of isolates (>30.0%) producing extended-spectrum beta-lactamases (ESBL). Even the new fluoroquinolones showed limited activity against Klebsiella spp. (72.1-88.6% susceptible) and the P. aeruginosa isolates showed high resistance rates to most antimicrobial agents tested. The results of this survey endorse the importance of Enterobacteriaceae as cause of UTI in Latin America. Our results also demonstrate that the uropathogens isolated in the Latin American medical centers exhibit high resistance to various classes of antimicrobial agents. Carbapenem-resistant P. aeruginosa, ciprofloxacin-resistant E. coli, ESBL-producing K. pneumoniae constitute serious problem in this geographic region.

Antibiotic susceptibility of bacterial strains isolated from patients with community-acquired urinary tract infections

Isolates from urine samples obtained during 1999 were identified and their susceptibility to antimicrobial agents studied along with any production of extended-spectrum beta-lactamases (ESBL) by Escherichia coli and Klebsiella pneumoniae. A total of 13774 samples were analysed using an automatic system for the detection of bacterial ATP (Coral, USA). Of these samples, 49% were reported to be positive and uncontaminated; bacteria most frequently isolated were E. coli (47%), Proteus mirabilis (7%), Enterococcus faecalis (6%) and K. pneumoniae (5%). The susceptibility studies showed 37% E. coli strains resistant to amoxycillin+clavulanate 33% to cotrimoxazole and 22% to ciprofloxacin. Seven strains of E. coli produced ESBL. Thirteen per cent of strains were resistant to cefuroxime but only (1%) to fosfomycin. Resistance to nitrofurantoin in K. pneumoniae was 38%. P. mirabilis showed 52% resistance to cotrimoxazole and 13% Staphylococcus aureus, were methicillin-resistant. E. faecalis did not show any special resistance to normal medication. Fosfomycin continued to show high activity against Gram-negative bacilli. However, enterococci, some species of staphylococci and yeasts were difficult to treat empirically. ESBL were detected in the isolates of E. coli and there were some methicillin-resistant strains of S. aureus.

Use of antibiotics to treat bacteriuria of pregnancy in the Nordic countries. Which antibiotics are appropriate to treat bacteriuria of pregnancy?

Bacteriuria in pregnancy with or without clinical symptoms is frequent and increases the risk of pyelonephritis, preterm labour, and low birth weight infants. Commonly used antibiotics such as ampicillin (pivampicillin), amoxicillin, trimethoprim, and sulphonamide are currently associated with a high degree of resistance of the most common pathogen in the urinary tract, Escherichia coli. During the past few decades a number of new and efficient antibacterial antibiotics have been developed. The presumption that a specific drug is safe for both the pregnant woman and the foetus depends on how widely the drug has been used. A recent survey among general practitioners and obstetricians in Denmark, Finland, Norway, and Sweden confirmed that the beta-lactam antibiotic pivmecillinam and nitrofurantoin are the most commonly used agents in the treatment of bacteriuria in pregnancy in the Nordic countries. However, a surprisingly high number of physicians reported that they prescribe sulphonamides during the first two trimesters in spite of resistance of E. coli and possible adverse effects on the foetus.

Quality measures of antimicrobial drug use

Antimicrobial use is the major determinant in the development of resistance. Many parameters of importance for optimal quality of antimicrobial therapy have already been defined. Maximal efficacy of the treatment should be combined with minimal toxicity at the lowest cost. Quality of antimicrobial drug use is dependent on knowledge of many aspects of infectious diseases. Considering efficacy, many of our indications for antimicrobial use need critical evaluation. Irrational use should be discouraged. Avoidance of the development of resistance is a quality parameter that will need increasing attention. This paper reviews the well-established factors that may influence the appropriateness of pharmacotherapy with antimicrobial drugs. It cites recent evidence supporting principles of prudent prescribing and gives an overview of audits that have addressed these parameters. Measures relating to resistance are discussed.

Resistance of bacteria in urinary tract infections

Bacterial infection of the urinary tract is a common health problem in young women but also the most common nosocomial infection (>33%) contributing to the mortality of patients, and increasing the duration and cost of hospitalization. Escherichia coli is the most predominant organism and its prevalence varies in different studies. The high consumption of inappropriately prescribed antibiotics, combined with multiple pathology and frequent use of invasive devices, is a major factor contributing to high levels of resistance. There is a serious decrease in susceptibility of E. coli strains to amoxycillin, due to the presence of R-TEM enzymes, to cotrimoxazole and trimethoprim. Nitrofurantoin and fosfomycin-trometamol remain highly active against urinary Enterobacteriaceae, with over 90% of E. coli being susceptible. Knowledge of the most likely causative organisms and the prevalence of resistance pathogens to antimicrobial agents is essential to select antibiotics and to establish guidelines for the empirical treatment of urinary tract infections.

Comparison of pivmecillinam and cephalexin in acute uncomplicated urinary tract infection

The clinical and bacteriological efficacy of a 3-day course of pivmecillinam, 200 mg three times daily, was compared with that of a 7-day course of cephalexin, 250 mg four times daily, in 216 patients with a bacteriologically confirmed, acute, uncomplicated, urinary tract infection. Both treatments were similarly effective. Clinical cure or improvement was obtained in 95.3% of patients given pivmecillinam and in 93.6% of patients given cephalexin. Bacteriological success was achieved in 89.7 and 81.7% patients taking pivmecillinam or cephalexin, respectively. Eradication rates for Escherichia coli were 90.1% for pivmecillinam and 80.6% for cephalexin. Both treatments were well tolerated. This study has confirmed that a 3-day course of pivmecillinam is effective and well tolerated in uncomplicated cystitis.

Antibiotic Selection for Urinary Tract Infection: New Microbiologic Considerations

Urinary tract infection (UTI) is an extremely common clinical condition, especially among women, half of whom will have at least one episode of acute cystitis at some point during adult life. An estimated one quarter of these women will have frequent, recurrent UTI. The microbiology of uncomplicated UTI is very predictable, with the vast majority of cases attributed to Escherichia coli. Recent reports from the United States and Europe have shown that resistance among uropathogens to agents that have traditionally been recommended as firstline therapy for uncomplicated UTI is on the rise. Although resistance to fluoroquinolone antibiotics among community-acquired uropathogens remains very low in the United States, fluoroquinolone resistance in community-acquired UTI isolates from other parts of the world has been increasingly described. Very low levels of resistance to nitrofurantoin among uropathogens has revived interest in this agent. The effect of in vitro resistance in uropathogens on the clinical response to treatment of acute cystitis is not well studied. The implications of emerging resistance among the causative agents of this extremely common infection for therapy of UTI are discussed.

Antibiotic sensitivity of bacteria associated with community-acquired urinary tract infection in Britain

Twelve laboratories in different parts of Britain each supplied approximately 80 consecutive urinary bacterial isolates from community patients. All strains were identified by a central laboratory, where sensitivity to a variety of orally administered antimicrobials was determined by microtitre broth dilution. 65.1% of isolates were Escherichia coli, 23.4% 'coliforms' other than E. coli, 4.6% Proteus and Morganella spp., 1.8% Pseudomonas spp., 2.4% enterococci, 0.7% group B streptococci, 1.5% coagulase-negative staphylococci and 0.5% Staphylococcus aureus. Using previously published breakpoint sensitivity values, 98.9% of all isolates were found to be sensitive to norfloxacin and to ciprofloxacin, 95.7% to co-amoxiclav, 86.8% to nitrofurantoin, 77.4% to cephalexin, 75.6% to trimethoprim, 75.0% to cephradine and 51.7% to amoxycillin. There were some differences in sensitivities between centres, particularly those of the cephalosporins. Using standard breakpoints, submitting laboratories were found to overestimate sensitivity to nitrofurantoin and to underestimate sensitivity to the quinolones and to co-amoxiclav; there was considerable overestimation of sensitivity to cephalosporins.