[Nocosomial urinary tract infections]

[Urinary tract infections in older adults: Etiology and antimicrobial susceptibilities in a southern area of Spain]

INTRODUCTION

Urinary tract infection (UTI) is one of the most prevalent diseases in clinical practice and increases in patients older than 65years compared to middle-aged patients. In order to improve empirical treatment, the etiology and antibiotic sensitivity profile of the most frequent bacteria that produce UTIs in older people have been studied.

MATERIAL AND METHODS

Cross-sectional, descriptive and retrospective study in which isolated micro-organisms with significant counts in urine samples from patients with UTI were included. The global etiology and according to sex were analyzed. Only one urine sample per patient and UTI episode was considered.

RESULTS

Regarding the origin of the sample, the highest proportion was in primary care with 4853 urine cultures (51.6% of positive urine cultures), followed by hospital care with 3565 urine cultures (46.4% of positive urine cultures) and 94 urine cultures in nursing homes elderly (2% positive urine cultures). Escherichia coli was the most isolated micro-organism both in the population as a whole (54%) and in each of the analyzed groups. It was observed that E.coli isolated in women was significantly higher than in men (χ², P=.044). Their sensitivity was: 80% fosfomycin and 75% amoxicillin-clavulanic acid.

CONCLUSIONS

E.coli continues to be the most frequently isolated micro-organism in UTI. Empirical treatment of UTI in our environment should include fosfomycin or amoxicillin-clavulanic acid, regardless of the health care unit and gender.

Factors Associated with Acute Community-Acquired Pyelonephritis Caused by Extended-Spectrum β-Lactamase-Producing Escherichia coli

This study aimed to identify the factors associated with the presence of extended-spectrum ß-lactamase-(ESBL) in patients with acute community-acquired pyelonephritis (APN) caused by Escherechia coli (E. coli), with a view of optimising empirical antibiotic therapy in this context. We performed a retrospective analysis of patients with community-acquired APN and confirmed E. coli infection, collecting data related to demographic characteristics, comorbidities, and treatment. The associations of these factors with the presence of ESBL were quantified by fitting multivariate logistic models. Goodness-of-fit and predictive performance were measured using the ROC curve. We included 367 patients of which 51 presented with ESBL, of whom 90.1% had uncomplicated APN, 56.1% were women aged ≤55 years, 33.5% had at least one mild comorbidity, and 12% had recently taken antibiotics. The prevalence of ESBL-producing E. coli was 13%. In the multivariate analysis, the factors independently associated with ESBL were male sex (OR 2.296; 95% CI 1.043-5.055), smoking (OR 4.846, 95% CI 2.376-9.882), hypertension (OR 3.342, 95% CI 1.423-7.852), urinary incontinence (OR 2.291, 95% CI 0.689-7.618) and recurrent urinary tract infections (OR 4.673, 95% CI 2.271-9.614). The area under the ROC curve was 0.802 (IC 95% 0.7307-0.8736), meaning our model can correctly classify an individual with ESBL-producing E. coli infection in 80.2% of cases.

Impact of whole-cell bacterial immunoprophylaxis in the management of recurrent urinary tract infections in the frail elderly

PURPOSE

This study aimed to determine the effectiveness of whole-cell bacterial immunotherapy, i.e. MV140 and autovaccines, in reducing the number ofurinary tract infections (UTIs)in frail elderly patients with recurrent UTI (RUTI).

METHOD

A prospective cohort observational study was performed including 200 frail elderly subjects suffering RUTI, both females and males, between 2016 and 2018. The effectiveness of autovaccines and the polybacterial formulation MV140 (Uromune®), consisting ofwhole-cell heat-inactivated Escherichia coli25%, Klebsiella pneumoniae25%, Proteus vulgaris25% andEnterococcus faecalis25% were evaluated. Subjects initiated a 3-month sublingually daily course with MV140 or autovaccine, either first treatment or a new course if they had been previously vaccinated prior to inclusion in the study. Number of UTIs and quality of life (QoL, SF-36 score) were measured in the different study groups.

RESULTS

The mean age for participants was 82.67 (SD, 7.12) for female and 80.23 (SD, 11.12) for male subjects. In all groups, 12 months following bacterial immunotherapy, the number of UTIs significantly decreased compared to before the treatment with autovaccine or MV140: the rate of reduction ranged between 7- and 40-fold. An increase in QoL scoring was also observed in any study group. When comparing medical interventions, MV140 conferred significantly higher benefit than autovaccines. For previously vaccinated individuals, a new 3-month course with MV140 or autovaccines provided further clinical improvement.

CONCLUSIONS

MV140 and autovaccines emerge as valuable immunoprophylaxis for the management of RUTI in the frail elderly, contributing to an improvement in patient's quality of life. Herein, MV140 has shown to confer a higher effectiveness compared to autovaccines, regardless sex or course of treatment.

Factores de riesgo y estrategias de prevención para el desarrollo de estrechez uretral de origen iatrogénico: Papel del urólogo

La estrechez uretral constituye una patología con morbilidad importante en el sexo masculino. Se evidencia en la actualidad un cambio en la frecuencia de las etiologías, con la disminución de causas inflamatorias y una transición hacia la iatrogenia como la más común. Mediante la búsqueda del estado del arte en cuanto a los procedimientos diagnósticos y terapéuticos conocidos como factores asociados a la estrechez uretral iatrogénica, se realizó una revisión narrativa de la literatura con el fin de describir y generar estrategias para su prevención. De los procedimientos terapéuticos que originan la estrechez uretral como complicación, el sondaje vesical es la mayor causa (hasta 34,3%), seguido de la prostatectomía radical (29,9%). Una buena técnica de sondaje vesical orientada desde el adecuado entrenamiento del personal disminuye de forma considerable su incidencia. Por otra parte, la adecuada selección de tratamientos y aspectos técnicos en pacientes que requieren el manejo de patologías obstructivas del tracto urinario como la hiperplasia prostática y litiasis u oncológicas como el cáncer de próstata, son unas de las recomendaciones para la prevención de ese trastorno. El entendimiento de los factores de riesgo y la adherencia a las estrategias de prevención descritas buscan disminuir la incidencia de la estrechez uretral de origen iatrogénico.

Linfopenia y riesgo de infecciones nosocomiales en ancianos en una institución de salud de Bogotá, Colombia. Estudio de casos y controles

Objetivo: La linfopenia se ha propuesto como un potencial factor asociado al riesgo de infecciones bacterianas nosocomiales (infección urinaria y neumonía), pero la magnitud y relevancia de este factor no ha sido evaluada formalmente. El objetivo de este estudio es determinar si existe asociación entre linfopenia e infecciones nosocomiales en ancianos hospitalizados en una institución de salud en Bogotá, Colombia. Métodos: Estudio de casos y controles, incluyendo personas mayores de 65 años hospitalizadas en el Hospital Universitario San Ignacio entre junio de 2016 y diciembre de 2017. Se consideraron casos aquellos con diagnóstico de infección nosocomial (neumonía, infección de vías urinarias, bacteriemia, infección de tejidos blandos) y se compararon con controles sin infección emparejados por edad y sexo. Se evaluó la asociación entre linfopenia e infección nosocomial mediante análisis bivariado y multivariado controlando por las variables de confusión. Resultados: Se incluyeron un total de 198 pacientes (99 casos y 99 controles). La prevalencia de linfopenia fue de 34.8%, sin encontrarse diferencia entre los dos grupos (p=0.88). La infección nosocomial se asoció a mayor incidencia de mortalidad (29.3 vs 10.1%, p>0.001) y mayor duración de estancia hospitalaria (Mediana 18 vs 9 días, p<0.01). Se encontró asociación entre infección nosocomial con enfermedad cardiovascular (OR = 2.87; IC 95% 1.37-6.00) y antecedente de cáncer (OR = 6.00; IC 95% 1.28-29.78), sin embargo, no hubo asociación con linfopenia (OR = 1.27; IC 95% 0.61-2.65). Conclusiones: Este estudio sugiere que no existe asociación entre linfopenia y el desarrollo de infecciones nosocomiales en pacientes ancianos.

Antimicrobial activity of endophytic fungi from the medicinal plants Mammea americana (Calophyllaceae) and Moringa oleifera (Moringaceae)

Introduction: Infectious diseases represent one of the leading causes of death worldwide. Considering the growing global challenge of antimicrobial resistance, research into new sources of potentially effective antimicrobial agents from natural origins is of great importance for world health. Objective: To evaluate the antimicrobial activity of endophytic fungi from Mammea americana and Moringa oleifera upon Staphylococcus aureus (ATCC 29213), S. aureus (resistant strain USb003), Escherichia coli (ATCC 25922), and E. coli (resistant strain USb007). Materials and methods: We isolated endophytic fungi from the leaves, seeds, and stems of the two plants under study. We evaluated their antimicrobial activity through the formation of sensitivity haloes in dual tests in vitro, as well as in trials using crude ethanolic extracts from the endophytes. The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and cytotoxicity o the substances were analyzed. Results: Three ethanolic extracts of Penicillium sp., Cladosporium (001), and Cladosporium (002) exhibited the greatest inhibition halos in sensitive and resistant strains of E. coli and S. aureus. The MIC and CBM found were statistically significant (p≤0.05) compared with the gentamicin control. Furthermore, the cytotoxicity test results of CC50>1,000 demonstrated that the endophytic fungi studied exhibit bactericidal characteristics without causing unintended damage. Conclusion: The endophytic fungi M. oleifera and M. americana represent a source of active secondary metabolites with antimicrobial and non-toxic properties. In light of these findings, further research should proceed with chemical identification of the compounds and the study of their mechanisms of action, especially given the paucity of current scientific knowledge concerning the isolation of endophytes in these plants.

Susceptibility evolution to antibiotics of Enterobacter cloacae, Morganella morganii, Klebsiella aerogenes and Citrobacter freundii involved in urinary tract infections: an 11-year epidemiological surveillance study

INTRODUCTION

The objective of this study was to analyse the susceptibility to antibiotic of Citrobacter freundii, Klebsiella aerogenes, Enterobacter cloacae, Serratia marcescens, Providencia stuartii and Morganella morganii (CESPM group), detected in urine cultures.

METHODS

Between 2006 and 2016 we analyzed CESPM group Enterobacteria isolated from urine cultures from both primary health-care centers and Hospital Virgen de las Nieves (Granada). We studied the susceptibility to aminoglycosides, fosfomycin, nitrofurantoin, quinolones, piperacillin/tazobactam, cefepime, imipenem and trimethoprim/sulfamethoxazole following CLSI interpretation criteria.

RESULTS

A total of 736 isolates were studied: 30.57% E. cloacae, 23.50% M. morganii, 20.38% K. aerogenes, 10.32% C. freundii, 8.83% S. marcescens and 6.38% P. stuartii. A significant decrease in the antibiotic susceptibility was observed. Gentamicin, ciprofloxacin, imipenem and cefepime showed susceptibility over 80%.

CONCLUSIONS

E. cloacae, M. morganii and K. aerogenes were the most common isolates. Cefepime and imipenem are still a good empiric therapeutic alternative given its activity in vitro.

Direct medical costs of urinary tract infections by Gram-negative bacilli resistant to beta-lactams in a tertiary care hospital in Medellín, Colombia

Introduction: Urinary tract infections are very frequent in the hospital environment and given the emergence of antimicrobial resistance, they have made care processes more complex and have placed additional pressure on available healthcare resources. Objective: To describe and compare excess direct medical costs of urinary tract infections due to Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa resistant to beta-lactams. Materials and methods: A cohort study was conducted in a third level hospital in Medellín, Colombia, from October, 2014, to September, 2015. It included patients with urinary tract infections caused by beta-lactam-susceptible bacteria, third and fourth generation cephalosporin-resistant, as well as carbapenem-resistant. Costs were analyzed from the perspective of the health system. Clinical-epidemiological information was obtained from medical records and the costs were calculated using standard tariff manuals. Excess costs were estimated with multivariate analyses. Results: We included 141 patients: 55 (39%) were sensitive to beta-lactams, 54 (38.3%) were resistant to cephalosporins and 32 (22.7%) to carbapenems. The excess total adjusted costs of patients with urinary tract infections due to cephalosporin- and carbapenem-resistant bacteria were US$ 193 (95% confidence interval (CI): US$ -347-734) and US$ 633 (95% CI: US$ -50-1316), respectively, compared to the group of patients with beta-lactam sensitive urinary tract infections. The differences were mainly found in the use of broad-spectrum antibiotics such as meropenem, colistin, and fosfomycin. Conclusion: Our results show a substantial increase in the direct medical costs of patients with urinary tract infections caused by beta-lactam-resistant Gram-negative bacilli (cephalosporins and carbapenems). This situation is of particular concern in endemic countries such as Colombia, where the high frequencies of urinary tract infections and the resistance to beta-lactam antibiotics can generate a greater economic impact on the health sector.

Risk factors and predisposing conditions for urinary tract infection

Understanding individual and population-specific risk factors associated with recurrent urinary tract infections (UTIs) can help physicians tailor prophylactic strategies. Frequent intercourse, vulvovaginal atrophy, change of the local bacterial flora, history of UTIs during premenopause or in childhood, family history, and a nonsecretor blood type are substantiated risk factors for recurrent uncomplicated UTIs. This is a narrative review based on relevant literature according to the experience and expertise of the authors. Asymptomatic bacteriuria is generally benign; however, during pregnancy it is more common and is associated with an increased likelihood of symptomatic infection, which may harm the mother or fetus. Screening of pregnant women and appropriate treatment with antimicrobials must be balanced with the potential for adverse treatment-related outcomes; appropriate prophylaxis should be considered where possible. High-quality data are currently lacking on risks related to asymptomatic bacteriuria in pregnancy and further data in this hard-to-study population should be a primary concern for researchers. Incomplete voiding represents the primary risk factor for UTIs associated with conditions such as urinary incontinence and prolapse. Correcting the presence of residual urine remains the most effective prophylaxis in these populations. Bladder function alters throughout life; however, changes in function may be particularly profound in clinical populations at high risk of UTIs. Patients with neurogenic bladder will also likely have other evolving medical issues which increase the risk of UTIs, such as repeated catheterization and increasing residual urine volume. More aggressive antimicrobial prophylactic strategies may be appropriate in these patients. Again, the paucity of data on prophylaxis in these high-risk patients requires the attention of the research community.

A multicentre study investigating parameters which influence direct bacterial identification from urine

Rapid diagnosis is one of the best ways to improve patient management and prognosis as well as to combat the development of bacterial resistance. The aim of this study was to study parameters that impact the achievement of reliable identification using a combination of flow cytometry and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF-MS).The study was carried out in nine hospitals in Spain and included 1,050 urine samples with bacterial counts of 5x10⁶ bacteria/ml. MALDI-ToF-MS-based identification was performed according to a previously described protocol. Valid identification by direct MALDI-ToF-MS was obtained in 72.8% of samples, in 80.3% of samples found to be positive by culture, 32.2% of contaminated samples, and 19.7% of negative samples. Among the positives samples with a valid identification the concordance at the species level was 97.2%. The parameters related to success of direct identification were: high bacterial count, the presence of Escherichia coli as a pathogen and rod-bacteria morphology provided by flow cytometry. The parameters related to failure were a high epithelial cell (EC) count, a high white blood cell (WBC) count and urine samples obtained from in-patients. In summary, this multicentre study confirms previously published data on the usefulness and accuracy of direct MALDI-ToF-MS-based identification of bacteria from urine samples. It seems important to evaluate not only the bacterial count, but also other parameters, such as EC and WBC counts, bacterial species and morphology, and the health care setting, to decide whether the sample is suitable for direct identification.

Antiseptic urinary catheterization and maintenance of the bladder catheter

Catheter-related urinary tract infections are very common both in the community and in the acute hospital care setting, particularly in the critical care environment. In order to minimize this problem, it is essential to adopt a correct approach from insertion to withdrawal of the urinary catheter, and always perform proper antisepsis. There is too much information on antisepsis measures with no consistent results. The present article reviews the existing scientific evidence on the subject and establishes recommendations based on the evidence, in order to optimize outcomes. The entire process is complemented with considerations on how to secure proper management of the indwelling urinary catheter. This article is part of a supplement entitled "Antisepsis in the critical patient", which is sponsored by Becton Dickinson.

Evolution of the antibiotic-resistance of microorganisms causing urinary tract infections: A 4-year epidemiological surveillance study in a hospital population

BACKGROUND

Urinary tract infections (UTIs) are the leading cause of infection in hospitalised patients. In this study, we describe the most common pathogens involved in the development of UTIs in hospitalised patients, their antibiotic-sensitivity profile and the activity evolution of antibiotics in standard use for treating these infections.

METHODS

We retrospectively assessed the results of cultures and antibiograms from urine samples from adult patients hospitalised in the Hospital Complex Virgen de la Nieves (Granada, Spain) with a microbiological confirmation of UTI between January 2013 and December 2016.

RESULTS

We identified 4,347 microorganisms (3,969 bacteria and 378 yeasts). During the 4years of the study, Escherichia coli was the most common species isolated in both sexes; however, 62.9% of the UTIs were caused by other microorganisms. The presence of multiresistant microorganisms such as Acinetobacterspp. (1.2%) and extended-spectrum beta-lactamase-producing enterobacteria (10.0%) and carbapenemase-producing enterobacteria (0.3%) were also relevant findings. Imipenem, piperacillin-tazobactam and fosfomycin presented activity rates above 80%, considering all causal microorganisms of UTI, while the other tested antibiotics presented activity rates below 70%.

CONCLUSION

Imipenem and piperacillin-tazobactam were the most active antibiotics in hospital use, which makes them first-line antibiotics in the empiric treatment of UTIs in this healthcare setting. The use of other antibiotics should be limited to conditions of demonstrated or highly probable sensitivity.

Approach of clinicians to candiduria and related outcome in the elderly

OBJECTIVE

Candiduria is increasingly frequent in hospitalized debilitated patients. We aimed to evaluate the approach of clinicians to candiduria in the oldest old, and its effect on clearance and mortality.

MATERIAL AND METHODS

An observational study without intervention was carried out during 2012 and 2013 in three Spanish hospitals over patients with nosocomial candiduria aged 80 and over. Following a diagnostic algorithm, we assessed the appropriateness of antifungal therapy and analyzed the impact of the clinical approach (antifungal therapy, antibiotics discontinuation and catheter removal or replacement) on the outcome (mortality at 60 days and resolution, persistence or recurrence of candiduria).

RESULTS

Hundred and forty eight patients were included. Symptomatology was attributable to candiduria in 31 instances and 19 asymptomatic patients were found at risk of developing candidemia. In response to culture-results, 77 (52%) of patients were treated with antifungals, mainly fluconazole (97.4%). The use of pharmacological therapy was appropriate (P<0.05) but subtherapeutical doses of fluconazole were widely used and follow-up samples were scarcely submitted. At 60 days of diagnosis the mortality was high (29.7%). The replacement or removal of the catheter resulted in a decrease in mortality and the use of antifungal treatment was associated with recurrence (P<0.05).

CONCLUSIONS

In the absence of clinical practice guidelines with enough evidence, our study suggests that catheter removal should always be tried in the elderly with candiduria, since it reduces the mortality. The repetition of culture should help to better characterize the asymptomatic episodes, which are predominant, and to reduce the use of antifungals.

[Impact of an intervention to improve indwelling urinary catheter use and reduce urinary tract infections]

OBJECTIVE

To evaluate the impact of an intervention regarding the adequate use and improvement in the care of indwelling urinary catheters (IUC) and the frequency of catheter-associated urinary tract infections (CAUTI) in hospitalised patients.

MATERIAL AND METHODS

A quasi-experimental study was performed. Basic data on the use of IUC were recorded before and after the intervention, which consisted of training on IUC use and the implementation of reminders for their removal.

RESULTS

There were 197 patients in the pre-intervention period and 194 in the post-intervention period. There was a non-significant decrease in the prevalence (17.3% versus 15.3%) and days with IUC (4.8±5.8 versus 4.3±4.2). There was an increase in adequately prescribed (41.1% versus 61.9%; P<.001) and attached IUC (0% vs 38.1%; P<.001), and a decrease in the urine collection bags on the floor (26.4% vs 6,2%; P<.001). The increase in the appropriate indications for IUC (86.8% vs 92.3%) and the decrease in CAUTI incidence density (2.1 vs 1.2 episodes/1,000 catheter days) were not significant, although above the standards.

CONCLUSIONS

After the intervention there was a significant increase in the number of adequately prescribed and attached IUC, and a decrease in the number of urine collection bags on the floor. Improvement in IUC indication and frequency of CAUTI reached the quality standards. Educational activities and the use of reminders improve safety of hospitalised patients with IUC.