Modified Reporting of Positive Urine Cultures to Reduce Inappropriate Treatment of Asymptomatic Bacteriuria Among Nonpregnant, Noncatheterized Inpatients: A Randomized Controlled Trial.

DESIGNWe conducted a randomized, parallel, unblinded, superiority trial of a laboratory reporting intervention designed to reduce antibiotic treatment of asymptomatic bacteriuria (ASB).METHODSResults of positive urine cultures from 110 consecutive inpatients at 2 urban acute-care hospitals were randomized to standard report (control) or modified report (intervention). The standard report included bacterial count, bacterial identification, and antibiotic susceptibility information including drug dosage and cost. The modified report stated: "This POSITIVE urine culture may represent asymptomatic bacteriuria or urinary tract infection. If urinary tract infection is suspected clinically, please call the microbiology laboratory … for identification and susceptibility results." We used the following exclusion criteria: age <18 years, pregnancy, presence of an indwelling urinary catheter, samples from patients already on antibiotics, neutropenia, or admission to an intensive care unit. The primary efficacy outcome was the proportion of appropriate antibiotic therapy prescribed.RESULTSAccording to our intention-to-treat (ITT) analysis, the proportion of appropriate treatment (urinary tract infection treated plus ASB not treated) was higher in the modified arm than in the standard arm: 44 of 55 (80.0%) versus 29 of 55 (52.7%), respectively (absolute difference, -27.3%; RR, 0.42; P = .002; number needed to report for benefit, 3.7).CONCLUSIONSModified reporting resulted in a significant reduction in inappropriate antibiotic treatment without an increase in adverse events. Safety should be further assessed in a large effectiveness trial before implementationTRIAL REGISTRATION. clinicaltrials.gov#NCT02797613Infect Control Hosp Epidemiol 2018;814-819.

Discontinuation of reflex testing of stool samples for vancomycin-resistant enterococci resulted in increased prevalence.

Discontinuation of reflex testing of stool submitted for Clostridium difficile testing for vancomycin-resistant enterococci (VRE) led to an increase in the number of patients with healthcare-associated VRE bacteremia and bacteriuria (0.21 vs 0.36 cases per 1,000 patient-days; P<.01). Cost-benefit analysis showed reflex screening and isolation of VRE reduced hospital costs.

Costs and effects of screening and treating low risk women with a singleton pregnancy for asymptomatic bacteriuria, the ASB study.

BACKGROUND: The prevalence of asymptomatic bacteriuria (ASB) in pregnancy is 2-10% and is associated with both maternal and neonatal adverse outcomes as pyelonephritis and preterm delivery. Antibiotic treatment is reported to decrease these adverse outcomes although the existing evidence is of poor quality. METHODS/DESIGN: We plan a combined screen and treat study in women with a singleton pregnancy. We will screen women between 16 and 22 weeks of gestation for ASB using the urine dipslide technique. The dipslide is considered positive when colony concentration ≥105 colony forming units (CFU)/mL of a single microorganism or two different colonies but one ≥105 CFU/mL is found, or when Group B Streptococcus bacteriuria is found in any colony concentration. Women with a positive dipslide will be randomly allocated to receive nitrofurantoin or placebo 100 mg twice a day for 5 consecutive days (double blind). Primary outcomes of this trial are maternal pyelonephritis and/or preterm delivery before 34 weeks. Secondary outcomes are neonatal and maternal morbidity, neonatal weight, time to delivery, preterm delivery rate before 32 and 37 weeks, days of admission in neonatal intensive care unit, maternal admission days and costs. DISCUSSION: This trial will provide evidence for the benefit and cost-effectiveness of dipslide screening for ASB among low risk women at 16-22 weeks of pregnancy and subsequent nitrofurantoin treatment. TRIAL REGISTRATION: Dutch trial registry: NTR-3068.

Aplicabilidade do TTC para a detecção de bacteriúria / Applicability of TTC test to bacteriuria detection

Exames laboratoriais para detecção da infecção urinária com custo menor que da urocultura têm sidobuscados. O cloridrato de trifeniltetrazólio foi avaliado em 342 amostras de urina paralelamente à urocultura objetivando a detecção de bacteriúria significativa. Os resultados demonstraram que o teste apresenta boa sensibilidade (91,3%) e baixa especificidade (64,3%), com valor preditivo negativo de 99,0%. Apesar do teste não substituir a urocultura como método diagnóstico, pode ser recomendado para a triagem de bacteriúria, eliminando a realização da cultura em amostras negativas.

[Hospital-acquired urinary tract infections]. / Hospitalines slapimo taku infekcijos.

Urinary tract infections are responsible for 40-60% of all hospital-acquired infections. Increased age of patients and comorbid diseases render hospitalized patients more susceptible to infection. Almost 80% of hospital-acquired urinary tract infections are associated with urinary catheters, and only 5-10% of urinary infections are caused by invasive manipulations in the urogenital tract. Pathogens of hospital-acquired urinary tract infections are frequently multi-resistant, and antibiotic therapy can only be successful when the complicating factors are eliminated or urodynamic function is restored. For treatment of complicated hospital-acquired urinary tract infections, the antibiotics must exhibit adequate pharmacodynamic and pharmacokinetic properties: high renal clearance of unmetabolized form with good antimicrobial activity in both acidic and alkaline urine. For selection of empirical treatment of hospital-acquired urinary tract infections, it is necessary to evaluate localization of infection, its severity, possible isolates, and the most frequent pathogens in the department where patient is treated. The best choice for the starting the antimicrobial therapy is the cheapest narrow-spectrum effective antibiotic in the treatment of urinary tract infection until microbiological evaluation of pathogens will be received. Adequate management of urinary tract infections lowers the rate of complications, requirements for antibacterial treatment, selection of multi-resistant isolates and is cost effective.

Clinical and economic consequences of nosocomial catheter-related bacteriuria.

Indwelling catheters are strongly associated with the development of bacteriuria, which can lead to significant morbidity in hospitalized patients. This report, a review of the literature, evaluates the infectious outcomes of patients with indwelling catheters to determine the precise clinical and economic impact of catheter-related infection. Statistical pooling was used to estimate the incidence of bacteriuria in hospitalized patients with indwelling catheters. In addition, the proportion of patients with catheter-related bacteriuria in whom symptomatic urinary tract infection and bacteremia will develop was estimated through quantitative synthesis of previous reports. Costs were estimated by using microcosting techniques. Of patients who have indwelling catheters for 2 to 10 days, bacteriuria is expected to develop in 26% (95% confidence interval [CI], 23% to 29%). Among patients with bacteriuria symptoms of urinary tract infection will develop in 24%, (95% CI, 16% to 32%), and bacteremia from a urinary tract source will develop in 3.6% (95% CI, 3.4% to 3.8%). Each episode of symptomatic urinary tract infection is expected to cost an additional $676, and catheter-related bacteremia is likely to cost at least $2836. Given the clinical and economic burden of urinary catheter-related infection, infection control professionals and hospital epidemiologists should use the latest infection control principles and technology to reduce this common complication.

Is urine culture necessary to rule out urinary tract infection in young febrile children?

OBJECTIVE: To determine whether the absence of pyuria on the enhanced urinalysis can be used to eliminate the diagnosis of urinary tract infection, avoiding the need for urine culture and sparing large health care expenditures. DESIGN: Results of an enhanced urinalysis (hemocytometer counts and interpretation of Gram-stained smears) performed on uncentrifuged urine specimens obtained by catheter were correlated with urine cultures in young febrile children at the Children's Hospital of Pittsburgh Emergency Department. In a group of 4253 children (95% febrile) less than 2 years of age, pyuria was defined as > or = 10 white blood cells/mm3, bacteriuria as any bacteria on any of 10 oil immersion fields in a Gram-stained smear and a positive culture as > or = 50,000 colony-forming units/ml. A subgroup of 153 children with their first diagnosed urinary tract infection were enrolled in a separate treatment trial, acute phase reactants (peripheral white blood cell count, erythrocyte sedimentation rate and C-reactive protein) were obtained and 99Tc-dimercaptosuccinic acid renal scans were performed. RESULTS: The presence of either pyuria or bacteriuria and the presence of both pyuria and bacteriuria have the highest sensitivity (95%) and positive predictive value (85%), respectively, for identifying positive urine cultures. Because a white blood cell count in a hemocytometer is the technically simpler component of the enhanced urinalysis, we chose to analyze the false negative results and achievable cost savings of using pyuria alone as the sole criterion for omitting urine cultures. If in this study urine cultures had been performed only on specimens from children who had pyuria or were managed presumptively with antibiotics, cultures of 2600 (61%) specimens would have been avoided. Twenty-two of 212 patients with positive urine cultures would not have been identified initially. However, based on interpretation of acute phase reactants, initial 99Tc-dimercaptosuccinic acid scan results, response to management and incidence of renal scarring 6 months later, 14 of the 22 patients most likely had asymptomatic bacteriuria and fever from another cause. The remaining 8 patients probably had early urinary tract infection. CONCLUSIONS: The analysis of urine samples obtained by catheter for the presence of significant pyuria (> or = 10 white blood cells/mm3) can be used to guide decisions regarding the need for urine culture in young febrile children.

Screening and treatment of asymptomatic bacteriuria of pregnancy to prevent pyelonephritis: a cost-effectiveness and cost-benefit analysis.

OBJECTIVE: To compare the effectiveness, benefits, and costs of two asymptomatic bacteriuria screening and treatment strategies to prevent pyelonephritis in pregnancy. METHODS: A decision analytic model was created to compare strategies based on either 1) a leukocyte esterase-nitrite dipstick, or 2) on urine culture, with a policy of no screening or treatment. A literature search was conducted to generate probability estimates. Cost estimates were based on a local pharmacy and laboratory survey and supplemented by recent literature estimates. Sensitivity analyses were performed over wide ranges of probability and cost estimates. RESULTS: Under baseline assumptions, no screening resulted in 23.2 cases of pyelonephritis per 1000 pregnancies, versus 16.2 cases with the dipstick strategy and 11.2 with the culture strategy. The cost of screening and treatment of asymptomatic bacteriuria per 1000 pregnancies was $1968 with dipstick and $19,264 with culture. The cost of treating pyelonephritis with no screening was $57,562, versus $40,257 with dipstick and $27,832 with culture. Therefore, both the dipstick strategy and the culture strategy were cost-beneficial (based on a pyelonephritis cost of $2485) when compared with no screening. However, because it cost $3492 to prevent each additional case of pyelonephritis with culture that was not prevented by dipstick, the culture strategy was not cost-beneficial compared with the dipstick strategy. These results were sensitive to varying estimates for the prevalence of asymptomatic bacteriuria, the rate of progression of asymptomatic bacteriuria to pyelonephritis, the sensitivity of the dipstick, culture costs, and the cost of a case of pyelonephritis. CONCLUSION: When compared with a policy of no screening, screening for and treatment of asymptomatic bacteriuria to prevent pyelonephritis in pregnancy is cost-beneficial whether based on the leukocyte esterase-nitrite dipstick or on urine culture. However, the culture strategy is not cost-beneficial when compared with the dipstick strategy.

Characteristics of bacteriuria in a homogeneous maternity hospital population.

Bacteriuria and urinary tract infection are a common cause of morbidity in pregnancy. Recent evidence has, however, questioned the magnitude of this risk and the effectiveness of therapy in reducing it. To clarify matters, a prospective study on 3123 ante-natal women was carried out. Screening for bacteriuria was carried out by culturing a mid-stream specimen of urine. Treatment was given to all patients with a positive culture and was based on antibiotic sensitivity testing. Repeat culture was performed 1 week after completion of therapy. The prevalence of bacteriuria in our population was 4.74%. Over half of these patients were asymptomatic. 67% of those with bacteriuria at screening were symptomatic or had a past history of urinary tract infection. Escherichia coli was the predominant organism cultured. The most effective antibiotic was Nitrofurantoin, which was sensitive in over 90% of isolates. Late urinary tract infection occurred in 3.52% of patients. There was no increase in maternal or foetal complications amongst those with bacteriuria. We concluded that it might be more cost-effective to confine screening to those patients who are symptomatic or have a past history of urinary tract infection.

The limited usefulness of urine and blood cultures in treating pyelonephritis in pregnancy.

Although urine cultures are performed routinely in managing acute pyelonephritis in pregnancy, little is known about the clinical usefulness of these cultures. The same is true for blood cultures. To evaluate their role in managing patients, we reviewed the records of 156 cases to determine to what extent such cultures influenced treatment. Over 90% of urine isolates were sensitive to the initial antibiotic. Most changes in therapy were based on clinical response; only 3% of pre-treatment urine cultures and 2% of blood cultures led to a change in antibiotics. On a nationwide basis, urine and blood cultures cost $10-20 million each year. Our data suggest that more limited use of cultures will simplify management and save money without compromising patient care.

[The evaluation of different methods for rapid diagnosis in the detection of asymptomatic bacteriuria in pregnant women]. / Evaluación de diferentes métodos de diagnóstico rápido en la detección de bacteriuria asintomática en la gestante.

We compared the effectiveness of different methods of rapid diagnosis in the detection of asymptomatic bacteriuria in 74 females during the first trimester of pregnancy. The sensitivity, specificity and negative predictive value for the visual reading of nitrites, leukocyte sterase, bacteriuria and leukocyturia in the sediment and bacteria in Gram stain were 77%, 22%, 33%, 22% and 88%, 98%, 85%, 82%, 91% and 86%, and 97%, 89%, 90% and 90%, with and accuracy of 96%, 77%, 76%, 82% and 86%, respectively. The combination of visual readings of nitrites and Gram stain showed a sensitivity and negative predictive value of 100%. We conclude that if the reading of the reactive strip is negative, the likelihood of a positive culture is very small, and it is minimal when combined with Gram stain.

Screening for asymptomatic bacteriuria in pregnancy. A decision and cost analysis.

Screening women for asymptomatic bacteriuria on the first prenatal visit is a standard of obstetric care. Treating women with positive results decreases the risk of pyelonephritis and possible prematurity. This study uses decision and cost analysis to compare the utility of screening for asymptomatic bacteriuria with not screening. Data are based on published reports and average charges for services. Costs are based on 1988 charges, projected for the expected results of outpatient screening, possible suppressive therapy, and risks of pyelonephritis. Screening is based on the combined sensitivities and specificities of the MacConkey and CLED (cysteine-lactose-electrolyte-deficient agar) panels of the dip-slide culture. Under the baseline assumptions, the risk of pyelonephritis is estimated to be 2 cases per 100 screened women vs 3.5 cases per 100 unscreened women. The anticipated cost of screening 100 women is $9,939, compared with $12,824 for not screening 100 women. Screening is cost saving unless the cost of screening is above $26, the length of hospitalization for pyelonephritis is fewer than 2.2 days, the risk of asymptomatic bacteriuria falls below 2%, the risk of pyelonephritis with asymptomatic bacteriuria falls below 13%, or the efficacy of treatment in preventing pyelonephritis falls below 38%.