New directions in the diagnosis and therapy of urinary tract infections

Knitting Thread Devices: Detecting Candida albicans Using Napkins and Tampons

Reproducible and in situ microbial detection, particularly of microbes significant in urinary tract infections (UTIs) such as Candida albicans, provides a unique opportunity to bring equity in the healthcare outcomes of disenfranchised groups like women in low-resource settings. Here, we demonstrate a system to potentially detect vulvovaginal candidiasis by leveraging the properties of multifilament cotton threads in the form of microfluidic-thread-based analytical devices (μTADs) to develop a frugal microbial identification assay. A facile mercerization method using heptane wash to boost reagent absorption and penetration is also performed and is shown to be robust compared to other existing conventional mercerization methods. Furthermore, the twisted mercerized fibers are drop-cast with media consisting of l-proline β-naphthylamide, which undergoes hydrolysis by the enzyme l-proline aminopeptidase secreted by C. albicans, hence signaling the presence of the pathogen via simple color change with a limit of detection of 0.58 × 106 cfu/mL. The flexible and easily disposable thread-based detection device when integrated with menstrual hygiene products showed a detection time of 10 min using spiked vaginal discharge. The developed method boasts a long shelf life and high stability, making it a discreet detection device for testing, which provides new vistas for self-testing multiple diseases that are considered taboo in certain societies.

Reliability of dipstick assay in predicting urinary tract infection

Aims:

Urine dipstick analysis is a quick, cheap and a useful test in predicting Urinary Tract Infection (UTI) in hospitalized patients. Our aim is to evaluate the reliability (sensitivity) of urine dipstick analysis against urine culture in the diagnosis of UTI.

Materials and Methods:

Patients admitted to our hospital suspected of having UTI, with positive urine cultures were included in this study from a 2-year period (January 2011 to December 2012). Dipstick urinalysis was done using multistix 10 SG (Siemens) and clinitek advantus analyzer. The sensitivity of dipstick nitrites, leukocyte esterase and blood in these culture-positive UTI patients was calculated retrospectively.

Results:

Urine dipstick analysis of 635 urine culture-positive patients was studied. The sensitivity of nitrite alone and leukocyte esterase alone were 23.31% and 48.5%, respectively. The sensitivity of blood alone in positive urine culture was 63.94%, which was the highest sensitivity for a single screening test. The presence of leukocyte esterase and/or blood increased the sensitivity to 72.28%. The sensitivity was found to be the highest when nitrite, leukocyte and blood were considered together.

Conclusions:

Nitrite test and leukocyte esterase test when used individually is not reliable to rule out UTI. Hence, symptomatic UTI patients with negative dipstick assay should be subjected to urine culture for a proper management.

Evaluation of the diagnostic workup in young women referred for recurrent lower urinary tract infections

OBJECTIVES

To evaluate the current practice of the diagnostic workup in The Netherlands and the clinical relevancy of the outcome of various diagnostic procedures in young women referred for recurrent lower urinary tract infections (UTIs).

METHODS

A questionnaire was sent to all urologic departments in The Netherlands (n = 104) inquiring about the diagnostic procedures used for recurrent lower UTIs. Furthermore, we performed a prospective study in 100 consecutive young female patients (18 to 40 years old) referred for evaluation of recurrent lower UTIs. All patients underwent a standardized workup: questionnaire, voiding diary, physical examination, urinalysis and culture, abdominal x-ray with ultrasound or intravenous urography, and cystoscopy.

RESULTS

The response rate to the questionnaires was 92%. The standard procedures were laboratory blood tests in 56%, cystoscopy in 69%, plain abdominal x-ray in 91%, and abdominal ultrasound in 59%. Only 18% of the urologists asked every patient to make a voided urine frequency volume chart. In our group of patients, the radiologic procedures revealed only one relevant abnormality. Cystoscopy confirmed cystitis in 22 patients, but never revealed relevant findings. None of these diagnostic procedures ever contributed to the diagnosis. The 24-hour urine output was less than 1.5 L in 43 patients, which was considered insufficient. The individual self-reports of fluid intake were unreliable.

CONCLUSIONS

Many Dutch urologists perform an extensive routine workup in patients referred for recurrent lower UTIs. The results of our study revealed that the yield of most diagnostic procedures in these patients is low. The focus in evaluating these patients should be directed toward the behavioral aspects. Thus, the routine workup can be restricted to a voiding diary, urinalysis, and urine culture.

Urinary tract infection and pyelonephritis

UTIs are common, potentially severe infections that the emergency physician must manage efficiently and effectively. In most cases, this entity is well recognized, and the clinician will be confident of the correct course. However, in certain populations, complications are common, and the best therapy has yet to be proven. Tailoring the evaluation and treatment to the risk of complications is imperative. With careful evaluation, individualized therapy and close follow-up, the majority of patients can be expected to do well.

Utility of UB-92 data for monitoring emergency department performance improvement

The Universal Billing Code of 1992 (UB-92) is a standard database used by hospitals to generate itemized charges for patient visits. This study examined the use of UB-92 information to monitor emergency department performance improvement projects. UB-92 data were used to determine whether urine tests had been ordered for emergency department patients. A population of patients at low risk for requiring a urine culture was defined as discharged female patients between 16 and 60 years of age undergoing a urinalysis as part of their emergency department treatment during a 10-month period. Based on UB-92 data, only a total of 2,138 patients were identified who met the study's low-risk criteria. Recommendations for the optimum use of these tests were presented to the emergency physicians as part of departmental performance improvement activities. Additional logistical problems associated with the procedure for ordering this test were identified and corrected as part of this project. After an additional 5-month period, a second analysis of the entire 15 months of UB-92 data was performed. Prior to physician notification, 41.6% of low-risk patients underwent both a urinalysis and a urine culture and sensitivity in the emergency department. In the 5-month follow-up period, the percentage of patients undergoing both tests decreased 18% to only 23%.

Urinalysis and urinary tract infection: update for clinicians

Dysuria is a common presenting complaint of women and urinalysis is a valuable tool in the initial evaluation of this presentation. Clinicians need to be aware that pyuria is the best determinate of bacteriuria requiring therapy and that values significant for infection differ depending on the method of analysis. A hemocytometer yields a value of > or = 10 WBC/mm3 significant for bacteriuria, while manual microscopy studies show > or = 8 WBC/high-power field reliably predicts a positive urine culture. In cases of uncomplicated symptomatic urinary tract infection, a positive value for nitrites and leukocyte esterase by urine dipstick can be treated without the need for a urine culture. Automated urinalysis used widely in large volume laboratories provides more sensitive detection of leukocytes and bacteria in the urine. With automated microscopy, a value of > 2 WBC/hpf is significant pyuria indicative of inflammation of the urinary tract. In complicated cases such as pregnancy, recurrent infection or renal involvement, further evaluation is necessary including manual microscopy and urine culture with sensitivities.

Decision making, evidence, audit, and education: case study of antibiotic prescribing in general practice

OBJECTIVES

To describe a group general practice's implementation of a decision to prescribe 3 day courses of 200 mg trimethoprim twice daily for urinary tract infections in women and to compare 3 day courses with 5 and 7 day courses.

DESIGN

Record review, audit of trimethoprim prescribing for urinary tract infections, and critical appraisal of evidence originally presented in support of 3 day course.

SETTING

Group general practice in Newcastle upon Tyne.

DATA SOURCES

The records of all female patients aged 12 years and older who were prescribed trimethoprim for uncomplicated urinary tract infections during a 12 month period were reviewed. 271 valid records were identified.

DATA EXTRACTION

Prescribing rates for different courses of trimethoprim, rates of patients returning for second consultations, rates of urine cultures, results of cultures, results of critical appraisal of evidence.

RESULTS

114 of 271 (42%) prescriptions written at the first visit were for 3 day courses. 16 of 114 (14%) patients who had had a 3 day course of treatment returned for a second consultation compared with 6/83 (7.2%) of those who had had a 5 day course and 8/74 (11%) who had had a 7 day course. The difference between 3 day and 5 day courses in rates of returning for second consultations was 6.8% (95% CI -1.7% to 12.6%) and between 3 day and 7 day courses was 3.2% (-3.6% to 10.0%). Appraisal of the original evidence on which the practice based its recommendations showed that it was flawed. Additional evidence was found in the Cochrane Library.

CONCLUSIONS

Our original decision, made by consensus at a meeting of the practice's partners, had not led to a consistent change in practice. We did not find a significant increase in treatment failures among patients treated with the 3 day regimen.

Treatment of uncomplicated urinary tract infections: exploring differences in adherence to guidelines between three European countries. Drug Education Project Group

OBJECTIVE

To evaluate adherence of general practitioners to treatment guidelines regarding urinary tract infections in three European countries and to investigate whether differences in adherence at the prescribing level within and between countries could be explained by general practitioners' knowledge and attitudes, characteristics, or national setting.

DESIGN

Prescribing data collected in 1994-1995 were analyzed regarding use of first-choice drugs and duration of treatment, knowledge and attitudes were assessed with a questionnaire, and multiple regression analysis was used to explain differences in prescribing behavior within and between countries.

RESULTS

Our study is based on data from 85.6% of the 584 general practitioners who were scheduled to participate in a continuing education program. The mean proportion of responses in agreement with the guidelines regarding first-choice drugs was 0.69 in Sweden, 0.78 in the Netherlands, and 0.79 in Norway; regarding duration of treatment, the mean proportion was 0.56 in Sweden, 0.67 in the Netherlands, and 0.59 in Norway. The proportion of first-choice drugs prescribed for women (18-75 y) was 0.55 in Sweden, 0.83 in the Netherlands, and 1.00 in Norway (patients >16 y). The duration of treatment was 7.6 defined daily doses per prescription in Sweden, 5.9 in the Netherlands, and 6.6 in Norway. Knowledge and attitudes explained 0-17% of the variation in prescribing. Years in practice explained 0-11%, and the general practitioners' gender had no explanatory value. The national setting explained most of the variation between countries.

CONCLUSIONS

Differences in prescribing behavior can be explained only to a small extent by deviations from the guidelines in terms of knowledge and attitudes. Between countries, differences in regulation, marketing, and distribution of drugs seem to be of much greater importance.

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.

Medication use during the perinatal period

OBJECTIVE

To briefly describe the drug therapy administered during the perinatal period of pregnancy for common maternal and fetal complications, and to identify those agents that should not be used for these conditions.

DATA SOURCES

References were obtained from an ongoing literature search of peer-reviewed obstetric and gynecologic journals and other selected medical and pharmacy journals available in the English language. Primary search vehicle was a weekly review of the tables of contents of nearly 1,300 medical journals provided by Reference Update (Institute of Scientific Information, Philadelphia). MEDLINE searches were also conducted using key terms for each subtopic.

STUDY SELECTION

Specific references were selected for each topic based on the adequacy of their study design, patient population, and a recent publication date. Reviews were used if a large number of primary references would have been required to adequately describe the topic.

DATA EXTRACTION

Most references reflected the current opinions expressed in the Educational (Technical) Bulletin and Committee Opinion series published by the American College of Obstetricians and Gynecologists. Recent, well-conducted studies that arrived at different conclusions were also included.

DATA SYNTHESIS

Data obtained from each reference reflected the conclusions of the authors based on their research or an analysis of the research on others on the appropriate use of the drug(s) for the specific condition being treated.

CONCLUSION

Drug therapy during the perinatal period is frequently required and can be beneficial for the mother, fetus, and newborn. Many complications previously associated with severe morbidity and mortality, such as infections, premature rupture of membranes, preterm labor, hypertension, maternal pain during labor, and postpartum hemorrhage, are now controlled with appropriate pharmacologic therapy. All health professionals who provide services to pregnant women should be knowledgeable in this drug therapy.

Urinary tract infections

Urinary tract infections (UTIs) are still the precipitating cause for 7 million patient visits per year with total costs exceeding one billion dollars. Diagnostic modalities have become more "friendly" for the smaller laboratory with "dip stick" culture tests providing a rapid method of isolation of pathogens. In many cases, empiric therapy is more cost effective than culture in uncomplicated UTIs in women. The etiologic organisms implicated in UTIs have not changed dramatically over the past two decades, with E. coli still accounting for the majority of cases. Antibiotic susceptibility patterns have changed dramatically, with ampicillin losing utility die to the emergence of resistance. Quinolones, which have been exceedingly active against gram-negative enteric pathogens, are no longer universally active and more pathogenic organisms, such as pseudomonas, may be resistant. The emergence of other highly resistant organisms, such as Enterococcus faecium, must be watched for.

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.