Efficacy of single-dose and conventional amoxicillin therapy in urinary-tract infection localized by the antibody-coated bacteria technic

Single- and multiple-dose pharmacokinetics and tolerability of limaprost in healthy Chinese subjects

BACKGROUND AND OBJECTIVES

Limaprost, a prostaglandin E1 analogue, is used to treat various symptoms in patients with ischemic diseases. The present study was designed to determine the pharmacokinetics and tolerability of single and multiple oral doses of limaprost 5 μg tablets in healthy Chinese subjects.

METHODS

Single and multiple doses of 5-μg limaprost were orally administered to 12 healthy Chinese subjects. There was a 2-week washout period between single and multiple dosing. Blood samples were collected at various times. Indomethacin and aspirin were added to the blood samples to inhibit the endogenous release of prostaglandins during the sample processing. Plasma limaprost was measured by a two-dimensional liquid chromatography-tandem mass spectrometry method.

RESULTS

After single dosing, limaprost was rapidly absorbed (time to reach maximum plasma concentration [t max] = 22.50 min) and eliminated (elimination half-life [t ½] = 21.70 min), with the maximum plasma concentration (C max) being 2.56 pg/mL and area under the concentration-time curve (AUC) from time 0 to the last quantifiable time point (AUC0-t) being 70.68 pg·min/mL. There were significant inter-individual variations in the AUCs for both single- and multiple-dose regimens. The values of C max, AUC, t ½ and t max were not statistically different between single and multiple dosing. The accumulation factor R was 0.609 ± 0.432 (R < 1), indicating that there was no accumulation after multiple dosing. There were no statistically significant differences in pharmacokinetic parameters for both single and multiple dosing between female and male subjects. The drug was well tolerated, with no severe adverse events being observed.

CONCLUSIONS

Limaprost is rapidly absorbed after oral administration and is rapidly eliminated, with no accumulation after multiple dosing. The drug is well tolerated and no serious adverse events occurred.

Short- and long-term cure rates of short-duration trimethoprim-sulfamethoxazole treatment in female dogs with uncomplicated bacterial cystitis

Background

Long‐duration beta‐lactam antibiotics are used for empirical treatment in female dogs with uncomplicated bacterial cystitis. However, women with bacterial cystitis are treated with short‐duration potentiated sulfonamides because longer courses of beta‐lactams result in lower cure and higher recurrence rates.

Hypothesis/Objectives

Short‐duration potentiated sulfonamide treatment is more efficacious than long‐duration beta‐lactam treatment in achieving clinical and microbiological cures in female dogs with uncomplicated bacterial cystitis.

Animals

Thirty‐eight client‐owned female dogs.

Methods

Randomized, double‐blinded, placebo‐controlled clinical trial. Dogs were treated with TMP‐SMX (15 mg/kg PO q12h for 3 days followed by a placebo capsule PO q12h for 7 days; Group SDS; n = 20) or cephalexin (20 mg/kg PO q12h for 10 days; Group LDBL; n = 18). Dogs were monitored for clinical and microbiological cure during treatment and at short‐ and long‐term follow‐up.

Results

No statistically significant differences were found between treatment groups in clinical cure rates after 3 days of treatment (89% SDS, 94% LDBL; P = 1.00) and 4 days (85% SDS, 72% LDBL; P = .44) or >30 days (50% SDS, 65% LDBL; P = .50) after conclusion of treatment or in microbiological cure rates 4 days (59% SDS, 36% LDBL; P = .44) or >30 days (44% SDS, 20% LDBL; P = .40) after conclusion of treatment.

Conclusions and Clinical Importance

We did not identify a difference in cure rates between short‐duration sulfonamide and long‐duration beta‐lactam treatments in female dogs with uncomplicated cystitis. Long‐term cure rates in both treatment groups were low. In some female dogs, “uncomplicated” bacterial cystitis may be more complicated than previously recognized.

Three-day treatment of acute lower urinary tract infections in women. A double-blind study with amoxycillin and co-trimazine

The aim of this study was to determine if a three-day treatment of lower urinary tract infection (UTI) is effective. 215 women with symptoms of lower UTI, seen in general practice, were randomly allocated to a double-blind study and given either amoxycillin 1000 mg twice a day for three days or trimethoprim 90 mg/sulphadiazine 410 mg (co-trimazine) 2 tablets initially, then one tablet twice daily for three days. 157 women (73%) had significant bacteriuria. Therapeutic efficacy was evaluated in 146 patients. One week after treatment had started, 88% of the women in the amoxycillin group and 100% in the co-trimazine group were cured (p less than 0.01). After a follow-up period of four weeks, the cumulative relapse frequencies were 19% and 9% respectively. Adverse reactions were mild in most cases. Two patients, both on co-trimazine, had to discontinue treatment because of nausea and vomiting. Vulvovaginal irritation was more often reported by women treated with amoxycillin (n = 8) than by those treated with co-trimazine (n = 1) (p less than 0.05). It is concluded that a three-day course of amoxycillin or co-trimazine in lower UTI is safe, causes few adverse reactions, is simple to administer and comfortable for the patient. Co-trimazine seems to be more effective than amoxycillin.

Failure of excessive doses of ampicillin to prevent bacterial relapse in the treatment of acute pyelonephritis

In order to evaluate whether very high doses of ampicillin might be more effective than conventional therapy in eradicating bacteria in patients with acute pyelonephritis, 34 affected patients were randomly assigned into two treatment groups. One group was given ampicillin in a daily dose of 30 g for three days and 20 g for four days without further treatment. The other group was given ampicillin in moderate doses for one month. Out of 13 patients treated with excessive doses for one week, only three were completely cured whereas conventional therapy cured 9 out of 21. Thus, excessive doses of ampicillin given for one week were not more effective but more expensive and possibly less beneficial than conventional therapy.

One or three weeks' treatment of acute pyelonephritis? A double-blind comparison, using a fixed combination of pivampicillin plus pivmecillinam

The clinical and bacteriological effects of 1 and 3 weeks' pivampicillin plus pivmecillinam treatment were compared in a double-blind, randomized study of patients with acute pyelonephritis. Three weeks after the end of active treatment, clinical success was seen in 29 (91%) of the 32 patients on 1-week treatment, compared with 28 (97%) of the 29 patients treated for 3 weeks. Bacteriological success was seen in only nine (28%) patients in the 1-week group vs. 20 (69%) in the 3-week group (p = 0.004). This difference was mainly due to a large number of relapses of lower urinary tract infection in the 1-week group. Even in uncomplicated cases, the bacteriological result of the 1-week treatment was unsatisfactory. Side-effects were more common in the 3-week treatment group. In conclusion, 1-week treatment of patients with acute pyelonephritis is too short. Three weeks' treatment is effective in uncomplicated cases, but even longer treatment or low-dose prophylaxis is indicated in certain patients with predisposing factors.

Antibiotic duration for treating uncomplicated, symptomatic lower urinary tract infections in elderly women

BACKGROUND

Urinary tract infections (UTI) are common in elderly patients. Authors of non systematic literature reviews often recommend longer treatment durations (7 to 14 days) for older women, but the evidence for such recommendations is unclear.

OBJECTIVES

To determine the optimal duration of antibiotic treatment for uncomplicated symptomatic lower UTI in elderly women.

SEARCH STRATEGY

We contacted known investigators and pharmaceutical companies, screened reference lists of identified articles, reviews and books, and searched MEDLINE, EMBASE, CINAHL, Healthstar, Popline, Gerolit, Bioethics Line, The Cochrane Library, Dissertation Abstracts International and Index to Scientific & Technical Proceedings without language restriction. Date of most recent search: 7 May 2008.

SELECTION CRITERIA

All randomised controlled trials (RCTs) comparing different treatment durations of oral antibiotics for uncomplicated symptomatic lower UTIs in elderly women were included. Whenever possible we obtained outcome data for older women included in studies with a broader age range. We excluded patients with fever, flank pain or complicating factors; studies with treatment durations longer than 14 days and prevention studies.

DATA COLLECTION AND ANALYSIS

The two authors independently assessed study quality and extracted data. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) for dichotomous outcomes and mean difference (MD) for continuous outcomes with 95% confidence intervals (CI).

MAIN RESULTS

Fifteen studies (1644 elderly women) were included. Three studies compared single dose with short-course treatment (3 to 6 days), six compared single dose with long-course treatment (7 to 14 days) and six compared short- with long-course treatment. Methodological quality of all studies was low except for a more recent geriatric study. There was a significant difference for persistent UTI between single dose and short-course treatment (RR 2.01, 95% CI 1.05 to 3.84) and single versus long-course treatment (RR 1.93, 1.01 to 3.70 95% CI), in the short-term (< 2 weeks post-treatment) but not at long-term follow-up or on clinical outcomes. Patients preferred single dose treatment (RR 0.73, 95% CI 0.60 to 0.88) to long-course treatments, but this was based on one study comparing different antibiotics. Short versus longer treatments showed no significant difference in efficacy. Rate of adverse drug reactions increased significantly with longer treatment durations in only one study.

AUTHORS' CONCLUSIONS

Short-course treatment (3 to 6 days) could be sufficient for treating uncomplicated UTIs in elderly women, although more studies on specific commonly prescribed antibiotics are needed.

Antibiotic duration for treating uncomplicated, symptomatic lower urinary tract infections in elderly women

BACKGROUND

Urinary tract infections are common in elderly patients. Authors of non systematic literature reviews often recommend longer treatment durations (7-14 days) for older patients than for younger women, but the scientific evidence for such recommendations is not clear.

OBJECTIVES

To determine the optimal duration of antibiotic treatment for uncomplicated symptomatic lower urinary tract infections in elderly women.

SEARCH STRATEGY

We contacted known investigators and pharmaceutical companies marketing antibiotics used to treat urinary tract infections, screened the reference list of identified articles, reviews and books, and searched the following data bases: MEDLINE, EMBASE, CINAHL, Healthstar, Popline, Gerolit, Bioethics Line, The Cochrane Library, Dissertation Abstracts International, Index to Scientific & Technical Proceedings.

SELECTION CRITERIA

All randomized controlled trials in which different treatment durations of oral antibiotics for uncomplicated symptomatic lower urinary tract infections in elderly women were compared. We excluded patients with fever or flank pain and those with complicating factors. Trials with treatment durations longer than 14 days or designed for prevention of urinary tract infection were also excluded. No language restriction was applied.

DATA COLLECTION AND ANALYSIS

The quality of all selected trials was assessed and data extracted by the reviewers. Main outcome measures were persistence of urinary symptoms (short-term and long-term efficacy), effect on mental and functional status and adverse drug reactions. To compare the different treatment durations, we defined the following categories of duration: single dose, short course (3-6 days) and long course (7-14 days). Relative risk (RR) and 95% confidence intervals (CI) were calculated for each trial and outcome and were then combined using a random effects model.

MAIN RESULTS

Thirteen trials were included in this review. Six trials compared single dose with short-term treatment (3-6 days), three studies single dose with long-term treatment (7-14 days) and four trials short-term with long term treatment. Eight trials also included younger patients, but provided a subgroup analysis for elderly women. The methodological quality of all trials was low. All trials reported results of bacteriological cure rate; less often clinical outcomes (e.g. improvement or cure of symptoms) were analyzed. Only five trials compared the same antibiotic given for a different length of time. We performed a separate analysis for these trials. The rate of persistent bacteriuria rate at short-term (two weeks post-treatment) was better in the longer treatment group (3-14 days) than in the single dose group (RR 1.84, 95% CI 1.18 to 2.86). However, the rate of persistent bacteria at long term and the clinical cure rate showed no statistically significant difference between the two groups. Patients showed a preference for single dose treatment (RR 0.73, 95% CI 0.66 to 0.88), however this was based on only one trial comparing the same antibiotic. The comparison of short (3-6 days) and longer treatments (7-14 days) did not show any significant difference, but the number of included studies and sample size were low.

REVIEWER'S CONCLUSIONS

This review suggests that single dose antibiotic treatment is less effective but may be better accepted by the patients than longer treatment durations (3-14 days). In addition there was no significant difference between short course (3-6 days) versus longer course (7-14 days) antibiotics. The methodological quality of the identified trials was poor and the optimal treatment duration could not be determined. We therefore need more appropriately designed randomized controlled trials testing the effect, - on clinical relevant outcomes -, of different treatment durations of a given antibiotic in a strictly defined population of elderly women.

Short-course versus conventional length antimicrobial therapy for uncomplicated lower urinary tract infections in children: a meta-analysis of 1279 patients

OBJECTIVE

The objective was to compare the efficacies of single-dose, short-course (4 days or less), and standard course (5 days or greater) antimicrobial therapy for uncomplicated childhood cystitis.

METHODS

Prospective, randomized, controlled trials comparing 4 days or less of therapy (short courses) with 5 days or more of therapy (conventional therapy) were included if all of the subjects were <18 years of age, the initial infection was documented by urine culture, at least 1 subsequent culture was obtained between 3 and 30 days of enrollment, and some attempt was made to separate upper tract from lower tract infection. Composite differences among treatment groups were compared with a fixed or random effects model, depending on the test for heterogeneity.

RESULTS

Of the 517 citations identified by literature search, 37 were selected for detailed review, and 22 were included in the final meta-analysis. The overall difference in cure rates between short and conventional courses of therapy was significant (6.38%; 95% CI: 1.88% to 10.89%), favoring the conventional course. Similar results were obtained when only studies comparing the same agents in the short and conventional courses were included (7.92%; 95% CI: 2.09% to 13.8%). Short-course amoxicillin was inferior to conventional length course (difference in cure rate, 13%; 95% CI: 4% to 24%); no difference was found between short-course and conventional length courses of trimethoprim-sulfamethoxazole (difference in cure rate, 6.24%; 95% CI = -3.74% to 16.2%).

CONCLUSIONS

We conclude that single-dose amoxicillin is inadequate therapy for uncomplicated cystitis of childhood. Three days of trimethoprim-sulfamethoxazole therapy appears to be as effective as conventional length courses of the drug.

Treatment of pyelonephritis in adults

Although prescribing an antibiotic for the treatment of pyelonephritis seems to be a relatively easy task, a close look at the available data is disturbing. Optimal therapies for the different clinical syndromes of pyelonephritis have not yet been defined. The high failure rate suggests that in pyelonephritis (bacteria protected in the medulla) as well as in bacterial endocarditis (bacteria sequestered in vegetations) and in infections in neutropenic patients (host defenses not necessarily operating in conjunction with antibiotics), it may be necessary to maintain bactericidal levels at the site of infection (infected medulla) to achieve cure. Pharmacodynamic studies suggest that TMP/SMX, quinolones, and aminoglycosides, which penetrate well the infected renal parenchyma and are not impaired by the local inflammatory process, should, with the exception of pyelonephritis in pregnancy, be preferred to beta-lactams as first-choice agents for the therapy of gram-negative pyelonephritis.

Single daily doses of trimethoprim/sulphadiazine for three or 10 days in urinary tract infections

We conducted a prospective randomized study to evaluate the efficacy of a single daily dose of 4 mg/kg of trimethoprim coupled with 17.5 mg/kg of sulphadiazine for three (group 1) or 10 days (group 2) in the treatment of uncomplicated urinary tract infections in children. Forty patients (nine boys and 31 girls) aged 2.5-18 years, presenting with a urinary tract infection were allocated to one of the two groups. Patients were seen three, 10, and > or = 38 days after the initiation of treatment. Control urine cultures were negative in all patients at days 3 and 10. Two patients in group 1 and one patient in group 2 suffered a relapse within a month. Single doses of trimethoprim/sulphadiazine for three or 10 days are effective in the treatment of uncomplicated urinary tract infections in children.

Management of urinary tract infections in pregnancy: a review with comments on single dose therapy

Most investigators agree that the adverse effects of urinary tract infections in pregnancy can be abrogated by effective early detection and treatment. However, the optimal methods for screening and treatment remain controversial. Although single-dose therapy has not been applied to pregnant women with acute pyelonephritis, most but not all studies which have compared single-dose with longer courses of beta-lactam or other antibiotics in pregnant asymptomatic bacteriuric women have shown no differences in outcome. This paper reviews recent trials of single-dose treatment of bacteriuria in pregnant women.

Optimal characteristics of agents to treat uncomplicated urinary tract infections

The optimal characteristics of agents to treat uncomplicated urinary tract infection must include activity against the major pathogens involved in these infections as well as a low potential for development of bacterial resistance. High urinary levels should be present for an adequate period to eliminate the organisms. Side effects should be minimal with minimal effect on the bacterial flora of the community. Treatment programs of single-dose, three days, or five days can be developed depending upon the agent.

The pathobiology of subclinical pyelonephritis--an experimental evaluation

Clinical studies have demonstrated a poor correlation between localization tests, which are designed to determine the site of urinary tract infection, and symptoms of upper urinary tract infection. One explanation is that microorganisms may be present in the kidney but not initiate an inflammatory response with associated symptoms. An animal model has been developed to obtain quantitative information on the comparative pathobiology of lesion-inducing and non-lesion-inducing infections. In this model, non-manipulated kidneys had acquired a persistent microbial flora within 48 hours of the lower urinary tract becoming infected. This bacterial invasion was not associated with gross or histologic changes within the renal parenchyma, but minor foci of inflammatory cells were seen beneath the epithelium lining the calyces. Ureteric urines from such kidneys contained many leukocytes and high numbers of bacteria. These results showed that the kidneys were infected, rather than colonized, and the term "subclinical" infection was appropriate. Antimicrobial agents were variably successful at eradicating the infection. These experimental observations support the concept of subclinical pyelonephritis and may explain the absence of symptoms in the clinically equivalent situation in humans.

Rapid isolation and presumptive diagnosis of uropathogens by using membrane filtration and differential media

Random urine samples from hospitalized patients (n = 550) and seeded sterile filtered urine samples (n = 730) were used to test a membrane filtration technique, Qualture (Future Medical Technologies International, Inc., West Palm Beach, Fla.), for the detection and identification of uropathogens. Results for each sample were compared with those obtained by the calibrated loop (0.01 ml) method to demonstrate the sensitivity of the method as a screening tool and the specificity of the presumptive diagnosis obtained from the pattern of growth on differential media. The medium was supplied as dehydrated nutrient pads (Sartorius AG, Goettingen, Germany) and was activated by rehydration by the addition of the liquid specimen. With a threshold of 10(4) CFU/ml defining a positive culture, the sensitivity of the Qualture was 100%. At lower levels of bacteriuria, the Qualture was more sensitive than the calibrated loop method. Significant infections were presumptively diagnosed at 4 h by filtration rather than at 24 h on agar medium. The specificity of uropathogen identification ranged from 99% for Enterococcus spp. to 83% for Pseudomonas spp. Citrobacter spp. could not be differentiated from Escherichia coli and Providencia spp. could not be differentiated from Proteus spp., which does not create a therapeutic dilemma. Filtration, isolation, quantitation, and presumptive diagnosis are performed in one step, without subculture. Membrane filtration is a sensitive and rapid technique, with the advantage that it can be used as a collection and transport device without the use of growth inhibitors.

Comparison of single-dose administration and three-day course of amoxicillin with those of clavulanic acid for treatment of uncomplicated urinary tract infection in women

In a double-blind randomized study we compared a single-dose amoxicillin-clavulanate combination with a regular 3-day regimen in 109 women with cystitis. Clinical cure rates at 7 and 28 days posttreatment were 78 versus 87% and 67 versus 78%, respectively. The 3-day regimen was significantly better (P less than 0.001) only in women with recurrent urinary tract infections.

Definitions, classification, and clinical presentation of urinary tract infections

Urinary tract infections encompass a spectrum of clinical and pathologic conditions involving various parts of the urinary tract. Each syndrome has its own unique epidemiology, natural history, and clinical manifestations. Basic terminology used in describing urinary tract infections is defined in this article. A classification of these infections and their clinical features is presented.

Management of acute pyelonephritis in an emergency department observation unit

STUDY OBJECTIVES

To determine whether moderately to severely ill patients with acute pyelonephritis can be treated successfully on an outpatient basis, and whether any aspect of history, physical examination, or initial laboratory data predicts failure of outpatient therapy and the need for hospitalization.

DESIGN

Retrospective chart review of all patients with a diagnosis of acute pyelonephritis seen during a three-year period.

SETTING

Emergency department observation unit of an urban teaching hospital serving residents of the city and county of Denver.

TYPE OF PARTICIPANTS

Women between the ages of 15 and 50 with symptoms, physical examination, and initial laboratory data consistent with a diagnosis of pyelonephritis.

INTERVENTIONS

Patients received IV antibiotics, rehydration, analgesics, and antiemetics in an observation unit for up to 12 hours, when they were either admitted to the hospital or discharged home on oral antibiotics.

MEASUREMENTS AND MAIN RESULTS

Sixty-three of 87 patients (72%) with acute pyelonephritis were managed successfully as outpatients, nine (22%) were hospitalized directly from the observation unit because they were considered to be too ill to go home, and five (6%) returned with persistent symptoms after ED therapy and were hospitalized. No clinical or laboratory variable predicted success or failure of ED observation unit therapy at the time of initial presentation.

CONCLUSION

In selected patients, the observation unit may be used to initiate therapy for acute pyelonephritis. Those with an adequate clinical response to initial treatment may be discharged on oral antibiotic therapy with appropriate follow-up.

Review of published studies on single dose therapy of urinary tract infections

The published studies of the use of single dose antimicrobial therapy for the treatment of urinary tract infection have been reviewed. In women and children a single dose of any of several antimicrobial agents was as effective as a course of treatment for uncomplicated urinary tract infections caused by Escherichia coli. Trimethoprim or co-trimoxazole are currently the preferred agents for single dose therapy. Failure of single dose therapy may prove to be a simple guide as to the need for further urinary tract investigation or more intensive therapy. Single dose antimicrobial therapy is now the treatment of choice for uncomplicated urinary tract infections.

Fosfomycin trometamol in a single dose versus norfloxacin for seven days in the treatment of uncomplicated urinary infections in general practice

The efficacy and tolerability of fosfomycin trometamol in a single dose of 3 g was compared with norfloxacin 400 mg b.i.d. for seven days in the treatment of adult female patients with uncomplicated urinary infections. 158 female patients with a mean age of 30 years who presented symptoms of dysuria and frequency with documented pyuria and bacteriuria on urinalysis (greater than or equal to 10(5) cfu/ml of urine) were initially included in the study. The total number of clinically and bacteriologically evaluable patients was 111, of which 61 received fosfomycin trometamol and 50 norfloxacin. One to two days after the double blind medication schedule for seven days, 55 of 60 patients (92%) in the fosfomycin trometamol group and 48 of 50 patients (96%) in the norfloxacin group were clinically cured. 37 patients without significant bacteriuria showed a clinical cure rate of over 90% in both therapy groups. Two to three days after the single dose treatment with fosfomycin trometamol the initial infecting pathogen was eradicated in 60 of the 61 patients (98%). One to two days after a seven day treatment with norfloxacin 48 of 50 patients (96%) showed an eradication of the initial infecting pathogen. Six weeks after the start of therapy 39/60 patients (65%) and 32/49 (65%) in the fosfomycin trometamol and norfloxacin groups respectively, remained free from urinary infection. The reinfection rate in both treatment groups was approximately 25%. The relapse rate in the post treatment evaluation period of four weeks was relatively low in both therapy groups, 5/49 patients (10%) in the norfloxacin group and 3/55 patients (6%) in the fosfomycin trometamol group, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Randomized clinical trial of rifampin-trimethoprim and sulfamethoxazole-trimethoprim in the treatment of localized urinary tract infections

To investigate whether 10 days of rifampin-trimethoprim (RIF-TMP) or 6 weeks of sulfamethoxazole-trimethoprim (SMX-TMP) would decrease the relapse rate in patients with acute uncomplicated upper urinary tract infections in comparison with 10 days of SMX-TMP, we randomized 189 patients to receive RIF-TMP or SMX-TMP in a ratio of 1:2. After the site of infection was established by the antibody-coated bacterium (ACB) test, patients with upper-tract infections who received SMX-TMP were again randomized and received either a total of 6 weeks or 10 days of therapy. All patients who received RIF-TMP were treated for 10 days. Clinical and microbiological evaluations were repeated at 2 and 6 weeks posttreatment. Eighty-five patients (54 ACB positive) received 10 days of RIF-TMP, 71 patients (45 ACB positive) received 10 days of SMX-TMP, and 18 patients (18 ACB positive) received 6 weeks of SMX-TMP. The overall recurrence rates in patients who received 10 days of therapy were 32% for RIF-TMP and 23% for SMX-TMP (P = 0.13). There were 12 (14%) relapses in the RIF-TMP group compared with 2 (3%) relapses in the SMX-TMP group (P = 0.01). In patients with upper-tract infections, the relapse rates were not statistically significantly different (P = 0.13). There were two (11%) recurrences (one relapse and one reinfection) in the 6-week treatment group. This 6% relapse rate was not different from the 4% relapse rate observed in patients with upper-tract infections who received 10 days of SMX-TMP. The number of patients who discontinued treatment because of an adverse effect in the 6-week SMX-TMP treatment group was significantly greater than those in the 10-day SMX-TMP treatment group (P=0.003) and the RIF-TMP treatment group (P=0.05). Ten days of SMX-TMP was as effective as 6 weeks of SMP-TMP or 10 days of RIF-TMP in the treatment of uncomplicated upper urinary tract infections and caused the fewest untoward effects.

Single-dose versus traditional therapy for uncomplicated urinary tract infections

In the treatment of uncomplicated urinary tract infection, single-dose therapy has appeared to be as efficacious as traditional 7-14 day therapy in women with cystitis without renal involvement. Current localizing techniques to differentiate between lower- and upper-tract disease are inadequate for routine clinical practice. As a result we have proposed that failure of cure with single-dose treatment may be the most specific test available to diagnose renal infection. Most of the published data on single-dose therapy involves treatment with either amoxicillin or trimethoprim-sulfamethoxazole. Single-dose therapy offers advantages over traditional therapy, including improved compliance, reduced adverse effects, and decreased cost. Appropriate patient selection is critical if the outcome of single-dose therapy is to be effective.

Effect of vancomycin hydrochloride on Staphylococcus epidermidis biofilm associated with silicone elastomer

Peritonitis is a major complication of continuous ambulatory peritoneal dialysis. Relapsing peritonitis after the cessation of antimicrobial therapy is frequently reported and often involves Staphylococcus epidermidis. To investigate the potential role of catheter-associated biofilm in the pathogenesis of relapsing peritonitis, we describe an in vitro model permitting the development of an S. epidermidis biofilm on silicone elastomer biomaterial. This model has been used to investigate the ability of vancomycin hydrochloride to kill biofilm-encased organisms by using an antibiotic regimen typical of peritonitis therapy. No significant differences were seen between vancomycin-exposed and control groups in biofilm viable and total cell counts after 10 days. Vancomycin-exposed silicone-associated biofilm populations decreased by only 0.5 log10 CFU/cm2 over the study period. MICs and MBCs for the original S. epidermidis suspension were 3.125 and 6.25 micrograms/ml, respectively. For biofilm homogenate suspensions, MICs were 3.125 micrograms/ml, but MBCs were greater than 400 micrograms/ml. These data indicate that the biofilm organisms associated with an indwelling peritoneal catheter may display a form of tolerance, thereby suggesting one possible mechanism behind relapsing peritonitis.

Single-dose antimicrobial therapy in the treatment of asymptomatic bacteriuria in pregnancy

Fifty obstetric patients with asymptomatic bacteriuria were treated by single-dose antimicrobial therapy. The immediate cure rate was 84% and the recurrence rate was 12%. Seven of the eight patients in whom single-dose treatment failed responded to subsequent 7-day therapy with the same drug, indicating renal involvement. A 50% recurrence rate in the group of patients in whom single-dose treatment failed was compared with a 5% recurrence rate in the group cured by single-dose therapy, which indicates that failure with single-dose antimicrobial therapy can serve as a therapeutic test to identify patients at high risk for recurrent bacteriuria and its sequelae during pregnancy. It is concluded that single-dose antimicrobial therapy is a safe and effective way to treat asymptomatic bacteriuria in pregnant patients without urologic problems in their history.

Nontyphoid salmonella urinary tract infections

Urinary tract infection caused by nontyphoid salmonella is rare. A case is described in a patient with acquired immunodeficiency syndrome who had multiple recurrences. A review of cases in which salmonella involved the urinary tract indicates that this infection usually occurs in patients who are structurally or immunologically compromised. Recurrence is expected and treatment plan should include an extended course of antibiotic therapy.

Single-dose ciprofloxacin at 100 versus 250 mg for treatment of uncomplicated urinary tract infections in women

Two single-dose regimens of ciprofloxacin, 100 and 250 mg, were compared in the treatment of uncomplicated urinary tract infections in women. Cure rates 5 days after therapy did not significantly differ, being 16 of 19 (84%) with the 100-mg dose and 17 of 19 (89%) with the 250-mg dose. Ciprofloxacin was well tolerated.

Single-dose gentamicin therapy of recurrent urinary tract infection in patients with normal urinary tracts

Results of single-dose therapy of urinary tract infections in pediatric patients have been contradictory mainly because of selection criteria. We evaluated the efficacy of a single dose of gentamicin in patients with normal urinary tracts and in whom urinary tract infections were recurrent. Twenty-one patients were included in the study, and a similar number in a conventional group given treatment for 10 days. Cure rate was 100% in both groups. The recurrence rates of 67% in the study and 52% in the conventional group were comparable. Single-dose therapy seems to have a role in the treatment of urinary tract infection in the absence of urinary tract malformation.

Nalidixic acid and trimethoprim/sulphamethoxazole as alternatives for short-term treatment of urinary infections

The efficacy of 3-day therapy with nalidixic acid in 16 children, and trimethoprim/sulphamethoxazole in 19 children, was studied prospectively in children with an acute infection of the lower urinary tract and compared with that of a conventional 10-day course with the same drugs. The immediate cure rate was 97% in the 3-day group and 90% in the 10-day group. During 3 months of follow-up there were altogether six re-infections in children given short-term treatment and six in the conventionally treated group. The results give further support for the suggestion that 3-day therapy is equivalent to 10-day treatment in uncomplicated urinary infections in children and that both nalidixic acid and trimethoprim/sulphamethoxazole are good alternatives in such an approach.

Single-dose amoxycillin in the treatment of bacteriuria in pregnancy and the puerperium--a controlled clinical trial

Ninety obstetric patients with significant bacteriuria were treated randomly with either a single dose of 3 g amoxycillin or with a conventional course of ampicillin over 7 days. Treatment groups were comparable in terms of age, gravidity and socioeconomic status, and the outcome of pregnancy in the two groups did not differ significantly. Cure rates, assessed at 1 week and 6 weeks after treatment, were not significantly different: 88% for single-dose treatment and 84% for conventional treatment. It is concluded that a single dose of 3 g amoxycillin is a safe, effective and acceptable treatment for bacteriuria in pregnancy and the puerperium.

Comparison of single-dose tetracycline hydrochloride to conventional therapy of urinary tract infections

Sixty-two women with signs and symptoms compatible with lower urinary tract infections were randomized to receive single-dose tetracycline (2 g), multi-dose tetracycline (500 mg four times per day for 10 days), or single-dose amoxicillin (3 g). Urine cultures were obtained upon entry into the study and on days 4, 14, and 28 after therapy. Single-dose tetracycline cured 12 of 16 (75%) of women with documented urinary tract infections, compared with 15 of 16 (94%) in the multi-dose tetracycline group and 7 of 13 (54%) receiving single-dose amoxicillin. Mild nausea in 3 of 20 patients (15%) was the only complication in the single-dose tetracycline group. Two grams of single-dose tetracycline is as effective as other reported regimens regardless of the susceptibility of the initial pathogen and has minimal toxicity.