The management of acute uncomplicated cystitis in adult women by family physicians in Canada

Microbiology testing and antibiotic treatment for urinary tract infections in general practice: a nationwide observational study

PURPOSE

Routine urine testing is recommended prior to antibiotic treatment for urinary tract infections (UTIs) among high-risk groups for complicated UTIs. This study aims to examine whether the proportion of UTI encounters where antibiotics are prescribed that have accompanying urine testing differs by patient groups.

METHODS

A retrospective analysis was conducted using records of general practice encounters for UTIs occurring between January 2013 and July 2018 in an Australian national database. We calculated the proportion of UTI encounters with antibiotics prescribed that had accompanying urine microbiology testing and the odds ratios for the likelihood of testing by patient groups using generalised estimating equations.

RESULTS

Of 132,688 UTI encounters with antibiotics prescribed, 95,800 (72.2%) were accompanied by urine testing. Among high-risk groups for complicated UTIs and expected to have a high likelihood of testing, we found pregnant women [82.6% vs. non-pregnant 72.3%, adjusted odds ratio (aOR) 1.82, 95% confidence intervals (CI) 1.55-2.12] and children aged 5-9 years (77.6% vs. 20-44 years 72.0%, aOR 1.33, 95% CI 1.22-1.45) had relatively high odds of testing. However, children aged < 5 years (68.7% vs. 20-44 years 72.0%, aOR 0.83, 95% CI 0.76-0.90), patients with recurrent UTIs (69.0% compared to first-onset UTIs 73.6%, aOR 0.81, 95% CI 0.79-0.83), and patients in residential aged care facilities (67.3% vs. not 72.3%, aOR 0.80, 95% CI 0.72-0.90) had relatively low odds of testing.

CONCLUSION

Our results suggest inconsistencies and potential underuse of urine testing when antibiotics were prescribed for high-risk groups in UTI management. Further antibiotic stewardship is needed to improve guideline-based antibiotic prescribing for UTIs.

Knowledge and Practice Discordance in Treating Urinary Tract Infections

BACKGROUND AND OBJECTIVES

Urinary tract infections (UTIs) are a common condition in women. Guidelines have been published on the diagnosis and management of such infections with the twin goals of improved patient safety and avoiding unnecessary health care costs. In this study we evaluated both physicians' knowledge of these guidelines, and whether that knowledge translates to their clinical practice.

METHODS

We performed a retrospective chart review of UTI management before and after an educational intervention in a family medicine residency. Two control sites were also included. We also assessed physicians' knowledge of current UTI management guidelines using an anonymous quiz.

RESULTS

At the intervention site, guideline adherence improved following the educational session. Inappropriate culture use decreased from 88% to 68% (P<.005) while first-line antibiotic use increased from 68% to 92% (P<.005). No such benefits were seen at the control sites. The control and intervention site providers did not differ in knowledge of antibiotic choice on the quiz (86% and 88% correct respectively, P=.85), but all control providers felt routine cultures were appropriate, whereas only 38% of the intervention providers did (P<.05).

CONCLUSIONS

A simple educational intervention made an impact on the management of UTI. Our results also highlighted that knowledge and practice are not always aligned.

Antibiotic Hybrids: the Next Generation of Agents and Adjuvants against Gram-Negative Pathogens?

The global incidence of drug-resistant Gram-negative bacillary infections has been increasing, and there is a dire need to develop novel strategies to overcome this problem. Intrinsic resistance in Gram-negative bacteria, such as their protective outer membrane and constitutively overexpressed efflux pumps, is a major survival weapon that renders them refractory to current antibiotics. Several potential avenues to overcome this problem have been at the heart of antibiotic drug discovery in the past few decades. We review some of these strategies, with emphasis on antibiotic hybrids either as stand-alone antibacterial agents or as adjuvants that potentiate a primary antibiotic in Gram-negative bacteria. Antibiotic hybrid is defined in this review as a synthetic construct of two or more pharmacophores belonging to an established agent known to elicit a desired antimicrobial effect. The concepts, advances, and challenges of antibiotic hybrids are elaborated in this article. Moreover, we discuss several antibiotic hybrids that were or are in clinical evaluation. Mechanistic insights into how tobramycin-based antibiotic hybrids are able to potentiate legacy antibiotics in multidrug-resistant Gram-negative bacilli are also highlighted. Antibiotic hybrids indeed have a promising future as a therapeutic strategy to overcome drug resistance in Gram-negative pathogens and/or expand the usefulness of our current antibiotic arsenal.

Trimethoprim-sulfamethoxazole treatment increases the Pig-a mutant frequency in peripheral blood from severely malnourished rats

Severe malnutrition is a complex condition that increases susceptibility to infections. Thus, drugs are extensively used in malnutrition cases. In the present study, we assessed the mutagenic effects of combined trimethoprim and sulfamethoxazole (TMP-SMX) treatment in undernourished (UN) and well-nourished (WN) rats. Six-week-old UN and WN Han-Wistar rats were treated with TMP-SMX at a daily dose of 10 mg/kg/d TMP and 50 mg/kg/d SMX for 5 or 10 days. Blood was collected from the tail vein one day before (day -1) and 15, 30, and 45 days after TMP-SMX administration. The Pig-a mutant frequencies (MFs) in peripheral blood reticulocytes (RETs) and erythrocytes (RBCs) were measured through flow cytometry. Severe malnutrition increased the basal MFs in RETs (RET CD59-) and RBC (RBCs CD59-). These findings support the hypothesis that severe malnutrition is mutagenic even in the absence of exposure to an exogenous mutagen. UN and WN rats treated for 5 or 10 consecutive days with TMP-SMX had significantly increased and sustained Pig-a mutant frequencies, demonstrating the mutagenic effects of this drug.

Uncomplicated urinary tract infections in the emergency department: a review of local practice patterns

OBJECTIVES

To determine the number of urine cultures ordered for women who presented to the emergency department (ED) with symptoms of uncomplicated UTI, and whether a culture result impacted subsequent management.

METHODS

This was a retrospective chart review of non-pregnant women aged 18-39 presenting to one of two academic EDs with a discharge diagnosis of uncomplicated UTI over a one-year study period. Patients were excluded if there was documentation of fever, immunocompromised state, diabetes mellitus, absence of lower urinary tract symptoms, ED administration of intravenous antibiotics, a previous UTI treated with antibiotics in the last 90 days, two weeks post-partum or post-instrumentation.

RESULTS

Of the 512 charts included in the analysis, 494 (96.5%) patients had a urinalysis, of which 463 (93.7%) had positive leukocyte esterase and 90 (18.2%) had positive nitrites. 370 patients (72.3%) had urine cultures performed, of which 236 (63.8%) were positive. 505 (98.6%) patients received antibiotics (53.9% Macrobid; 22.6% Ciprofloxacin; 15.0% Septra; 6.7% other; 1.8% not documented). 7 (1.9%) cultures grew organisms resistant to the prescribed antibiotic; 2 (0.5%) patients received new prescriptions.

CONCLUSIONS

For the majority of young female patients with an uncomplicated UTI, urine cultures did not change management in the ED setting. However, when the diagnosis is uncertain based on symptomology and urinalyses alone, a urine culture may be warranted. Greater efforts should be directed towards educating emergency physicians on accurately diagnosing uncomplicated cystitis and the limited impact of urine cultures on treatment once a diagnosis has been made.

Metronidazole or Cotrimoxazole therapy is associated with a decrease in intestinal bioavailability of common antiretroviral drugs

Metronidazole (MTZ) and Cotrimoxazole (CTX) are used in HIV/AIDS patients eligible for antiretroviral treatment. The objective of this animal study was to determine whether pre-treatment with antibiotics affects the intestinal bioavailability of Atazanavir (ATV) and Ritonavir (RTV). After oral administration of 1 mg MTZ and CTX for 7 days, the rat colonic mucosa were analyzed for mucus thickness or placed in Ussing chambers to measure ATV and RTV net transepithelial fluxes (J_net). 1. In control rats, the mucus thickness was 43.3±7.6 µm and 40.7±6.9 µm, in proximal and distal colon, respectively. In proximal colon, the thickness was 57.2±8.8 and 58.2±6.9 µm after MTZ and CTX, respectively whereas in distal colon, the thickness was 121.1±38.4 and 170.5±35.0 µm (P<0.05) respectively. 2. Transepithelial conductance was reduced after MTZ or CTX in the proximal and distal colon. 3. In control, net ATV secretion was observed both in proximal (−0.36±0.02 µg.hr⁻¹ cm⁻²) and distal colon (−0.30±0.08 µg.hr⁻¹ cm⁻²). After MTZ and CTX, it was increased in the proximal colon by two 2 fold and 4 fold, respectively and in the distal colon by 3 fold and 5 fold, respectively. 4. In control, there was no net active RTV transport either in proximal (+0.01±0.01 µg.hr⁻¹ cm⁻²) or distal colon (+0.04±0.01 µg.hr⁻¹ cm⁻²). After MTZ and CTX, secretion was increased 5 fold and 10 fold, respectively, in the proximal colon and two fold and 5 fold, respectively in the distal colon (p<0.001). In conclusion, after MTZ and CTX therapy, the mucus layer was enlarged, passive permeability was decreased and ATV and RTV were actively secreted by the colonic epithelium suggesting that, in rat, the intestinal bioavailability of ATV and RTV is impaired after antibiotic therapy.

Voided midstream urine culture and acute cystitis in premenopausal women

BACKGROUND

The cause of acute uncomplicated cystitis is determined on the basis of cultures of voided midstream urine, but few data guide the interpretation of such results, especially when gram-positive bacteria grow.

METHODS

Women from 18 to 49 years of age with symptoms of cystitis provided specimens of midstream urine, after which we collected urine by means of a urethral catheter for culture (catheter urine). We compared microbial species and colony counts in the paired specimens. The primary outcome was a comparison of positive predictive values and negative predictive values of organisms grown in midstream urine, with the presence or absence of the organism in catheter urine used as the reference.

RESULTS

The analysis of 236 episodes of cystitis in 226 women yielded 202 paired specimens of midstream urine and catheter urine that could be evaluated. Cultures were positive for uropathogens in 142 catheter specimens (70%), 4 of which had more than one uropathogen, and in 157 midstream specimens (78%). The presence of Escherichia coli in midstream urine was highly predictive of bladder bacteriuria even at very low counts, with a positive predictive value of 10(2) colony-forming units (CFU) per milliliter of 93% (Spearman's r=0.944). In contrast, in midstream urine, enterococci (in 10% of cultures) and group B streptococci (in 12% of cultures) were not predictive of bladder bacteriuria at any colony count (Spearman's r=0.322 for enterococci and 0.272 for group B streptococci). Among 41 episodes in which enterococcus, group B streptococci, or both were found in midstream urine, E. coli grew from catheter urine cultures in 61%.

CONCLUSIONS

Cultures of voided midstream urine in healthy premenopausal women with acute uncomplicated cystitis accurately showed evidence of bladder E. coli but not of enterococci or group B streptococci, which are often isolated with E. coli but appear to rarely cause cystitis by themselves. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases.).

Does clinical examination aid in the diagnosis of urinary tract infections in women? A systematic review and meta-analysis

Background

Clinicians should be aware of the diagnostic values of various symptoms, signs and antecedents. This information is particularly important in primary care settings, where sophisticated diagnostic approaches are not always feasible. The aim of the study is to determine the probability that various symptoms, signs, antecedents and tests predict urinary tract infection (UTI) in women.

Methods

We conducted a systematic search of the MEDLINE and EMBASE databases to identify articles published in all languages through until December 2008. We particularly focused on studies that examined the diagnostic accuracy of at least one symptom, sign or patient antecedent related to the urinary tract. We included studies where urine culture, a gold standard, was preformed by primary care providers on female subjects aged at least 14 years. A meta-analysis of the likelihood ratio was performed to assess variables related to the urinary tract symptoms.

Results

Of the 1, 212 articles identified, 11 met the selection criteria. Dysuria, urgency, nocturia, sexual activity and urgency with dysuria were weak predictors of urinary tract infection, whereas increases in vaginal discharge and suprapubic pain were weak predictors of the absence of infection. Nitrites or leukocytes in the dipstick test are the only findings that clearly favored a diagnosis of UTI.

Conclusions

Clinical findings do not aid in the diagnosis of UTI among women who present with urinary symptoms. Vaginal discharge is a weak indicator of the absence of infection. The urine dipstick test was the most reliable tool for detecting UTI.

Overestimation error and unnecessary antibiotic prescriptions for acute cystitis in adult women

BACKGROUND

Empiric antibiotic prescribing for suspected acute cystitis may lead to unnecessary prescriptions when urine cultures are negative. This study assessed whether physician overestimation of the likelihood of bacterial infection contributed to unnecessary antibiotic prescriptions.

METHODS

This was a cross-sectional study in Toronto, Canada, from 1998 to 2000 of 231 women 16 years and older who underwent standardized clinical assessments and urine culture testing. The main outcome was an unnecessary antibiotic prescription, defined as a prescription where the urine culture was negative. The difference between physician estimates of the likelihood of a positive urine culture and the measured culture rate for women with similar symptoms was used to measure overestimation error. Logistic regression was used to assess associations between unnecessary prescriptions and clinical factors or overestimation error. Multiple logistic regression was used to adjust for the effect of clinical factors.

RESULTS

Of 230 women assessed, 186 (80.9%) were prescribed antibiotics and 74 (32.2%) were prescribed an unnecessary antibiotic where the urine culture was negative. When an overestimation error above the median value (14.75%) was present, the odds of an unnecessary antibiotic prescription were increased (adjusted odds ratio = 3.72; 95% confidence interval = 1.75-7.89). A high overestimation error was associated with the symptoms of urinary frequency or suprapubic tenderness and costovertebral angle tenderness on examination.

CONCLUSIONS

Physician overestimation of the likelihood of a positive urine culture in women with symptoms of acute cystitis was associated with unnecessary antibiotic prescribing. Antibiotic overuse may be reduced by developing treatment strategies that deemphasize nonspecific clinical findings that contribute to physician overestimation error.

[Regional audit on fluoroquinolones usage in the hospital and the community: are these antibiotics over-used?]

AIM OF THE STUDY

The ecological impact of an over-use or a mis-use of fluoroquinolones (FQs) appears of great importance according to published data. With the objective to set up a regional antibiotic stewardship program, we conducted a regional audit on FQs usage.

MATERIAL AND METHODS

[corrected] Ninety general practionners and 15 health care facilities participated to this prospective study. Overall, 511 prescriptions were evaluated (276 from hospital physicians and 235 [46%] from general practionners). The compliance of FQs prescription with national recommendations and with a regional referential was assessed. This regional referential was established in order to preserve FQs.

RESULTS

Only 14,3% of the prescriptions complied with the regional referential, even if the choice of FQs were in accordance with national recommendations in 56,8% of the prescriptions. Urinary tract infections (mostly non-complicated) were the most common indication for FQs prescription.

CONCLUSION

Analysis of FQs prescriptions shows that there is a significant potential for FQs preservation in Franche-Comté.