Single dose quinolone treatment in acute uncomplicated urinary tract infection in women

Efficacy and safety of quinolones for the treatment of uncomplicated urinary tract infections in women: a network meta-analysis

INTRODUCTION AND HYPOTHESIS

Uncomplicated urinary tract infection (uUTI) is defined as the presence of pathogenic organisms in the urinary tract without anatomical and functional abnormalities, is accompanied by inflammatory leukocytes and cytokines and may or may not develop clinical symptoms. The frequency of uncomplicated urinary tract infection is higher in young women. Several quinolone treatment regimens are available; however, since we do not know which is the best antibiotic regimen for the treatment of this urinary infection, we analyzed the published evidence and conducted a systematic review with network meta-analysis. The aim was to compare and hierarchize quinolones according to their efficacy and safety and to identify the best treatment for uncomplicated urinary tract infection in women through a systematic review with network meta-analysis.

METHODS

Medline, Embase, LILACS, Cochrane CENTRAL and other databases were searched for trials. Bias in the trials was assessed using the Cochrane Collaboration tool. To analyze efficacy and adverse events, for direct comparisons, we obtained risk ratios and 95% confidence intervals by applying a fixed-effects model using tau² and Q² tests to calculate the heterogeneity. For the network meta-analysis, we analyzed the indirect comparisons by Bucher's method.

RESULTS

We included 18 trials (8765 women). For premenopausal women, ofloxacin had a 57% probability of achieving remission but an 83% frequency of adverse events. For postmenopausal women, ofloxacin was 82% more effective for remission, with a 49% frequency of adverse events, compared with other types of quinolones.

CONCLUSIONS

Compared with other quinolones, ofloxacin 200 mg once daily for a treatment duration < 3 days provides the highest clinical and bacteriological remission rates with the lowest relapse and resistance rates for the treatment of women with uUTIs. However, additional trials are needed to confirm our findings, especially when the treatment duration exceeds 3 days.

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.

Clinical utility of the new fluoroquinolones for treating respiratory and urinary tract infections

Increasing antimicrobial resistance among most common urinary and respiratory tract pathogens has been the catalyst for the development of fluoroquinolones that are effective against these prevalent resistant organisms. Important attributes of the newly developed fluoroquinolones include once-daily dosing, maintained extensive tissue penetration and high oral bioavailability added to targeted antibacterial activities, all pharmacodynamic characteristics that may reduce the need for parenteral therapy or prevent patients being hospitalised. Some fluoroquinolones also offer same-dose bioequivalency between iv. and oral formulations, a feature that allows iv.-to-oral dosing (step-down or 'switch' therapy) without the need for dosage adjustments. These features suggest that the newer fluoroquinolones may be near-ideal agents for the empirical treatment of many common infections. This review discusses the efficacy and clinically relevant antimicrobial and pharmacokinetic qualities of the fluoroquinolones in comparison with other agents traditionally used to treat patients with urinary and respiratory tract infections.

Use of norfloxacin in poultry production in the eastern province of Saudi Arabia and its possible impact on public health

Samples of market-ready chicken muscle and liver from 32 local broiler farms were first screened for antibiotic residues by microbiological assay. The antibiotic-residue-positive muscles and livers from 22 farms were further analysed for norfloxacin (NFX) residues by high performance liquid chromatography. NFX was detected in 35.0% and 56.7% of raw antibiotic-residue-positive muscles and livers, respectively. The NFX-positive muscles and livers were respectively obtained from 11 (50.0%) and 14 (63.6%) of the 22 antibiotic-residue-positive farms. Since the maximum residue limit (MRL) for NFX has not yet been fixed, the MRL for enrofloxacin was used in the study. All NFX-positive farms had mean raw tissue levels, which were 2.7- to 34.3-fold higher than the MRL. Although cooking markedly reduced NFX tissue concentrations, mean detectable levels remained above MRL in large proportions of NFX-positive samples and farms. Susceptibility patterns of Enterobacteriaceae isolates from chicken and human patients to NFX showed alarmingly high rates of resistance in chicken isolates especially among Escherichia coli (45.9%) and Pseudomonas spp. (70.6%) compared with patients' isolates (10.5% and 18.2%, respectively). The study reveals widespread misuse of NFX in the local poultry industry, which may pose a major risk to public health including possible stimulation of bacterial resistance and hypersensitivity reactions to fluoroquinolones. More prudent use of fluoroquinolones in food-producing animals is therefore recommended. Further, there is a need to establish MRL values for NFX.

Clinical use of the fluoroquinolones

The appetite for modification to the basic quinolone nucleus has grown logarithmically since the first quinolone was employed in clinical practice. Important structural refinements have led to expanded microbiologic activity, optimal pharmacokinetics, and increased safety profiles. The practicing clinician and researcher may glean considerable information from the quinolone structure with regard to microbiologic spectra and safety before administering these agents to patients. Although some toxicities can be ominously predictable, such as with the so-called high-risk quinolones (e.g., double-halogenated and trifluorinated quinolones), clinicians must rely on animal models of toxicity and clinical trial data to discern other toxicities (e.g., Q-Tc interval prolongation). A few quinolones enjoy a relatively clean safety profile and are well tolerated (e.g., gatifloxacin, levofloxacin, ciprofloxacin). Other quinolones may be associated with significant collateral system toxicity during therapy; however, under certain conditions, albeit rare, their potential for benefit may outweigh the existing risk. Clinafloxacin, for use in the management of lung infections caused by multiply resistant B. cepacia in cystic fibrosis patients, is an example of a risk that may be outweighed by its therapeutic benefit. Because there are many treatment alternatives within the clinician's armamentarium, the obligation is to select the safest, most therapeutically effective, and most cost-effective agent that is available. In addition to increasing mortality and morbidity, the development of toxicity or an adverse event during therapy may compromise the immediate effectiveness of treatment as well as affect the cost of the patient's care significantly. With the immediate abundance of quinolones available for use, the safest, most effective, and best-tolerated agents will likely emerge as the most appropriate therapeutic choices when a quinolone is indicated.

A review of clinical trials with fluoroquinolones with an emphasis on new agents

This review aims to provide a comparison between the antimicrobial spectra, pharmacokinetics and clinical efficacy of the newer fluoroquinolones with older agents in this class, as well as other antibiotics used to treat lower respiratory and urinary tract infections (LRTIs and UTIs) respectively. Increasing antimicrobial resistance among common uro- and respiratory pathogens has focused attention on the development of fluoroquinolones, which have a broad spectrum of activity and improved tissue penetration. The new and developmental quinolones can be administered on a once-daily basis and exhibit high oral bioavailability, which reduces the need for parenteral therapy in hospitalised patients and may therefore potentially reduce the need for hospitalisation. These attributes, coupled with their expanded spectrum suggest that the newer fluoroquinolones are so far the most ideal agents for the empirical treatment of many common infections.

Economic assessment of three antimicrobial therapies for uncomplicated urinary tract infection in women

This retrospective cohort study used North Carolina Medicaid paid-claims data to assess clinical and economic outcomes of treatments for urinary tract infection (UTI). The study population comprised female Medicaid recipients, between 15 and 64 years of age, with a paid claim filed for a primary diagnosis of UTI or acute UTI from January 1 to June 30, 1994, who were treated with ciprofloxacin, nitrofurantoin, or trimethoprim/sulfamethoxazole (TMP/SMZ). Patients had follow-up for 6 months after the primary diagnosis. Patients who did not receive further treatment for UTI with 1 of the 3 drugs within 30 days after initial treatment were assumed to be cured. Costs were measured as the sum of reimbursements for UTI-related medical services and drug treatments. Outcomes for 409 patients were assessed. Cure rates of initial treatment with ciprofloxacin, nitrofurantoin, and TMP/SMZ were 81%, 88%, and 93%, respectively. Cost-effectiveness ratios of initial treatment with the 3 drugs were $150.80, $81.20, and $69.00, respectively. When efficacy rates generated from published randomized clinical studies were applied, cost-effectiveness ratios for the 3 drugs were $130.96, $86.17, and $72.00, respectively. A decision model of treatment pattern and associated costs is presented. Several patient variables indicate that the ciprofloxacin group included more severe cases of UTI than did the other groups. Study limitations, confounders, and future research suggestions are discussed. Our results show that treatment for >7 days results in a better cure rate regardless of the drug used than does treatment for < or =7 days and that TMP/SMZ is the most cost-effective of the 3 drugs for UTI or acute UTI.

Clinical applications of quinolones

The quinolone antimicrobials are the class of inhibitors of bacterial topoisomerases that has been developed most fully for clinical use in human medicine. Initial members of the class had their greatest potency against Gram-negative bacteria, but newly developed members have exhibited increased potency against Gram-positive bacteria and soon agents will be available with additional activity against anaerobic bacteria, providing a broad spectrum of potency. After nalidixic acid, the earliest member of the class which was used for treatment of urinary tract infections, the later fluoroquinolone congeners have had sufficient potency, absorption, and distribution into tissue for additional uses in treatment of sexually transmitted diseases, infections of the gastrointestinal tract, respiratory tract, skin, and bones and joints. Tolerability of these agents in usual doses has been good. Acquired bacterial resistance resulting from clinical uses has occurred in particular among staphylococci and Pseudomonas aeruginosa. Intense drug use and ability of resistant pathogens to spread have also contributed to development of resistance in initially more susceptible pathogens such as Escherichia coli and Neisseria gonorrhoeae in certain settings. Preservation of the considerable clinical utility of the quinolone class for the long term will be affected by the extent to which their use is judicious.

Antibiotic use in the emergency department. IV: Single-dose therapy and parenteral-loading dose therapy

There are a number of infectious diseases that can be treated efficaciously with a single dose of an antimicrobial agent. Other infections that can be treated with oral antibiotics on an outpatient basis may resolve more quickly if a parenteral loading dose is given in the emergency department (ED) prior to discharge. This article reviews the supporting literature and indications for single-dose and parenteral first-dose-loading antimicrobial therapy in the ED. This approach may be appropriate for such diverse infections as streptococcal pharyngotonsillitis, otitis media, urinary tract infections, chlamydial genital infections, vaginitis due to yeast, bacteria, or trichomoniasis, pneumonia, gonorrhea and pelvic inflammatory disease, and pediatric fever without a source.

Management of bacterial urinary tract infections in adults

OBJECTIVE

To provide a comprehensive review of the diagnosis and therapeutic management considerations in patients with urinary tract infections (UTIs).

DATA SOURCES

A MEDLINE search was used to identify pertinent English language literature, including reviews. Infectious disease textbooks were used for background information.

STUDY SELECTION

Clinical trials evaluating drug therapy in a variety of patient populations with UTIs were reviewed.

DATA EXTRACTION

Background information was obtained from comprehensive reviews. Drug dosing strategies and efficacy comparisons were extracted from the investigations in this area.

DATA SYNTHESIS

Information was processed to provide general guidelines and resources for practitioners to use in managing UTIs.

CONCLUSIONS

There are a number of useful antibiotics for the management of UTIs. The distinctions between infection severity and underlying risk factors within a given population influence the appropriateness of drug selection and duration of treatment.

Effects of ciprofloxacin, norfloxacin, and ofloxacin on in vitro adhesion and survival of Pseudomonas aeruginosa AK1 on urinary catheters

Pretreatment of urinary silicone latex catheters in vitro with 0.1 and 0.5 microgram of ciprofloxacin per ml for 1, 24, and 48 h significantly reduced the adhesion and survival of the clinical isolate Pseudomonas aeruginosa AK1. UV spectroscopy and high-performance liquid chromatography confirmed the presence of ciprofloxacin adsorbed onto the catheters and showed that up to 56% of the drug leached into the surrounding fluid within 24 h. Scanning electron microscopy demonstrated that the adherent organisms were malformed and elongated after exposure to ciprofloxacin. Transmission electron microscopy showed the presence of fimbriae on the bacterial surfaces, but there was no conclusive evidence of changes in the fimbriae upon exposure to ciprofloxacin. It was found that a significant eradication of 24-h Pseudomonas biofilms could be achieved with ciprofloxacin as well as with ofloxacin and norfloxacin. Preincubation of catheters with 50- and 100-micrograms/ml concentrations of ciprofloxacin resulted in up to a 99% reduction in the number of adherent bacteria in comparison with the reduction on control catheters. In addition, adherent biofilms were eradicated by 24 h of challenge with 50 and 100 micrograms of ciprofloxacin per ml at pH 7.0 and 5.5. Results of these in vitro studies suggest that there could be a clinical role for fluoroquinolones in preventing and treating urinary tract infections associated with P. aeruginosa adherence to prosthetic devices.

Use of adhesion counts to help predict symptomatic infection and the ability of fluoroquinolones to penetrate bacterial biofilms on the bladder cells of spinal cord injured patients

There were three objectives to the present study: (1) compare the bladder infection rate and extent of biofilm formation for seven untreated spinal cord injured (SCI) patients and seven given prophylactic co-trimoxazole, (2) identify a level of bacterial adhesion to bladder cells which could be used to help predict symptomatic infection, and (3) determine from in vivo and in vitro studies whether fluoroquinolones were effective at penetrating bacterial biofilms. The results showed that the infection rate had not changed with the introduction of prophylaxis. However, the uropathogenic population had altered subsequent to the introduction of prophylaxis with E. coli being replaced by E. faecalis as the most common cause of infection. In 63% of the specimens from asymptomatic patients, the bacterial counts per cell were < 20, while 81% of specimens from patients with at least one sign and one symptom of urinary tract infection (UTI) had > 20 adherent bacteria per bladder cell. Therefore, it is proposed that counts of > 20 bacteria adherent to sediment transitional epithelial bladder cells may be predictive of symptomatic UTI. Clinical data showed that fluoroquinolone therapy reduced the adhesion counts to < 20 per cell in 63% of cases, while trimethoprim-sulfamethoxazole only did so in 44%. Further in vitro testing showed that ciprofloxacin (0.1, 0.5 and 1.0 micrograms/ml) partially or completely eradicated adherent biofilms from 92% of spinal cord injured patients' bladder cells, while ofloxacin did so in 71% cases and norfloxacin in 56%. These findings have important implications for the detection and treatment of bacteriuria in spinal cord injured patients.

Effective postcoital quinolone prophylaxis of recurrent urinary tract infections in women

A total of 33 sexually active, premenopausal and postmenopausal women, suffering from recurrent urinary tract infections was randomized to receive postcoital prophylaxis with a dose of either 100 mg. ofloxacin (12), 200 mg. norfloxacin (11) or 125 mg. ciprofloxacin (10). While 130 urinary tract infections occurred in these patients during a mean of 8 months before postcoital quinolone prophylaxis, only 1 occurred during a mean of 15 months following prophylaxis. This difference was statistically highly significant. Each of these patients ingested a mean of 117 quinolone doses per year of postcoital prophylaxis. Before prophylaxis 74% of the introital cultures yielded gram-negative enterobacteria (mainly Escherichia coli), whereas only 11% yielded the same bacteria following prophylaxis. Postcoital oral prophylaxis with minimal quinolone doses is highly effective in the prevention of recurrent urinary tract infections in women, because it achieves high urinary bactericidal concentrations, and clears the majority of the introital and urethral Enterobacteriaceae without inducing resistance to the quinolones despite long-term treatment. This prophylaxis is highly recommended because of its ease of compliance, preservation of drug efficacy, lack of toxicity and cost-effectiveness. Postcoital quinolone prophylaxis is as good as or better than daily quinolone prophylaxis and uses only a third of the amount of drug consumed in daily prophylaxis.