Urinary tract infection in geriatric and institutionalized patients

Diagnostic accuracy of dipsticks for urinary tract infections in acutely hospitalised patients: a prospective population-based observational cohort study

OBJECTIVE

To determine the added diagnostic value of dipsticks for urinary tract infections (UTI) in acutely hospitalised individuals.

DESIGN

Prospective population-based cohort study.

SETTING

North Denmark.

PARTICIPANTS

All adults (≥18 years) examined with dipsticks at emergency departments in North Denmark Region from September 20 through 23 October 2021.

MAIN OUTCOME MEASURES

UTI was defined as ≥1 symptom of new-onset frequency, dysuria or suprapubic tenderness combined with a positive urine culture. Positive dipsticks were defined as any reaction for leucocyte esterase and/or nitrite.

RESULTS

Dipsticks were used in 1052/2495 (42%) of acutely hospitalised patients with a median age of 73 years (IQR 57-82) and 540 (51%) were female. Overall, 89/1052 (8%) fulfilled the UTI criteria and urine cultures were done in 607/1052 (58%) patients. Among patients examined with both dipstick and urine culture, sensitivity and specificity for UTI were 87% (95% CI 78% to 93%) and 45% (95% CI 41% to 50%). Positive and negative predictive values were 21% (95% CI 17% to 26%) and 95% (95% CI 92% to 98%), whereas positive and negative likelihood ratios were 1.58 (95% CI 1.41 to 1.77) and 0.30 (95% CI 0.18 to 0.51). Pretest probabilities of UTI ranged from 29% to 60% in participants with specific UTI symptoms with corresponding post-test probabilities of 35-69% if dipsticks were positive and 12-27% if dipsticks were negative. Results remained comparable if final clinical diagnosis was used as outcome among all patients examined with dipsticks. Modified Poisson regression yielded an adjusted relative risk of 4.41 (95% CI 2.40 to 8.11) for empirical antibiotics for UTI in participants without specific UTI symptoms and a positive dipstick.

CONCLUSIONS

Dipsticks yielded limited clinical decision support compared with a symptom-driven approach in this study and were independently associated with excess antibiotics for UTI.

Synthesis of a Phosphoethanolamine Cellulose Mimetic and Evaluation of Its Unanticipated Biofilm Modulating Properties

When coordinating and adhering to a surface, microorganisms produce a biofilm matrix consisting of extracellular DNA, lipids, proteins, and polysaccharides that are intrinsic to the survival of bacterial communities. Indeed, bacteria produce a variety of structurally diverse polysaccharides that play integral roles in the emergence and maintenance of biofilms by providing structural rigidity, adhesion, and protection from environmental stressors. While the roles that polysaccharides play in biofilm dynamics have been described for several bacterial species, the difficulty in isolating homogeneous material has resulted in few structures being elucidated. Recently, Cegelski and co-workers discovered that uropathogenic Escherichia coli (UPEC) secrete a chemically modified cellulose called phosphoethanolamine cellulose (pEtN cellulose) that plays a vital role in biofilm assembly. However, limited chemical tools exist to further examine the functional role of this polysaccharide across bacterial species. To address this critical need, we hypothesized that we could design and synthesize an unnatural glycopolymer to mimic the structure of pEtN cellulose. Herein, we describe the synthesis and evaluation of a pEtN cellulose glycomimetic which was generated using ring-opening metathesis polymerization. Surprisingly, the synthetic polymers behave counter to native pEtN cellulose in that the synthetic polymers repress biofilm formation in E. coli laboratory strain 11775T and UPEC strain 700415 with longer glycopolymers displaying greater repression. To evaluate the mechanism of action, changes in biofilm and cell morphology were visualized using high resolution field-emission gun scanning electron microscopy which further revealed changes in cell surface appendages. Our results suggest synthetic pEtN cellulose glycopolymers act as an antiadhesive and inhibit biofilm formation across E. coli strains, highlighting a potential new inroad to the development of bioinspired, biofilm-modulating materials.

Diagnosis of urinary tract infections in the hospitalized older adult population in Alberta

BACKGROUND

Urinary tract infections (UTIs) are one of the most common infections reported in older adults, across all settings. Although a diagnosis of a UTI requires specific clinical and microbiological criteria, many older adults are diagnosed with a UTI without meeting the diagnostic criteria, resulting in unnecessary antibiotic treatment and their potential side effects, and a failure to find the true cause of their presentation to hospital.

OBJECTIVE

The aim of this study was to evaluate the accuracy of UTI diagnoses amongst hospitalized older adults based on clinical and microbiological findings, and their corresponding antibiotic treatment (including complications), in addition to identifying possible factors associated with a confirmed UTI diagnosis.

METHODS

A single-center retrospective cross-sectional study of older adult patients (n = 238) hospitalized at the University of Alberta Hospital with an admission diagnosis of UTI over a one-year period was performed.

RESULTS

44.6% (n = 106) of patients had a diagnosis of UTI which was supported by documents clinical and microbiological findings while 43.3% (n = 103) of patients had bacteriuria without documented symptoms. 54.2% (n = 129) of all patients were treated with antibiotics, despite not having evidence to support a diagnosis of a UTI, with 15.9% (n = 37) of those patients experiencing complications including diarrhea, Clostridioides difficile infection, and thrush. History of major neurocognitive disorder was significantly associated with diagnosis of UTI (p = 0.003).

CONCLUSION

UTIs are commonly misdiagnosed in hospitalized older adults by healthcare providers, resulting in the majority of such patients receiving unnecessary antibiotics, increasing the risk of complications. These findings will allow for initiatives to educate clinicians on the importance of UTI diagnosis in an older adult population and appropriately prescribing antibiotics to prevent unwanted complications.

Drug allergy in older adults: A study from the United States Drug Allergy Registry

BACKGROUND

Older adults have an increased risk of adverse drug reactions and negative effects associated with alternative antibiotic use. Although the number of antibiotic allergies reported increases with age, the characteristics and outcomes of older adults receiving drug allergy assessment are unknown.

OBJECTIVE

To assess the characteristics and outcomes of drug allergy evaluations in older adults.

METHODS

We considered patients aged above or equal to 65 years enrolled in the United States Drug Allergy Registry (USDAR), a US multisite prospective cohort (January 16, 2019 to February 28, 2022). Data were summarized using descriptive statistics.

RESULTS

Of 1678 USDAR participants from 5 sites, 406 older adults aged above or equal to 65 years (37% 65-69 years, 37% 70-74 years, 16% 75-79 years, and 10% ≥80 years) received 501 drug allergy assessments. USDAR older adults were primarily of female sex (69%), White (94%), and non-Hispanic (98%). Most USDAR older adults reported less than or equal to 1 infections per year (64%) and rated their general health as good, very good, or excellent (80%). Of 296 (59%) penicillin allergy assessments in USDAR older adults, 286 (97%) were disproved. Other drug allergy assessments included sulfonamide (n = 41, 88% disproved) and cephalosporin (n = 20, 95% disproved) antibiotics. All 41 drug allergy labels in USDAR participants aged above or equal to 80 years and all 80 penicillin allergy labels in USDAR men aged above or equal to 65 years were disproved.

CONCLUSION

Older adults represented a quarter of USDAR participants but were neither racially nor ethnically diverse and were generally healthy without considerable antibiotic need. Most older adults presented for antibiotic allergy assessments, the vast majority of which were disproved. Drug allergy assessments may be underutilized in the older adults who are most vulnerable to the harms of unconfirmed antibiotic allergy labels.

Development and validation of a parsimonious prediction model for positive urine cultures in outpatient visits

Urine culture is often considered the gold standard for detecting the presence of bacteria in the urine. Since culture is expensive and often requires 24-48 hours, clinicians often rely on urine dipstick test, which is considerably cheaper than culture and provides instant results. Despite its ease of use, urine dipstick test may lack sensitivity and specificity. In this paper, we use a real-world dataset consisting of 17,572 outpatient encounters who underwent urine cultures, collected between 2015 and 2021 at a large multi-specialty hospital in Abu Dhabi, United Arab Emirates. We develop and evaluate a simple parsimonious prediction model for positive urine cultures based on a minimal input set of ten features selected from the patient's presenting vital signs, history, and dipstick results. In a test set of 5,339 encounters, the parsimonious model achieves an area under the receiver operating characteristic curve (AUROC) of 0.828 (95% CI: 0.810-0.844) for predicting a bacterial count ≥ 105 CFU/ml, outperforming a model that uses dipstick features only that achieves an AUROC of 0.786 (95% CI: 0.769-0.806). Our proposed model can be easily deployed at point-of-care, highlighting its value in improving the efficiency of clinical workflows, especially in low-resource settings.

BLEBBING OF THE PLASMA MEMBRANE OF LYMPHOCYTES IN THE POSTOPERATIVE PERIOD OF UROLITHIASIS

Urolithiasis is an urgent problem of surgical urology, about 200 thousand operations are performed annually in the Russian Federation. The complicated course of the postoperative period is accompanied by changes in homeostasis associated with immune activation and dysregulation of the endothelial system. The study evaluated the parameters of lymphocyte plasma membrane blebbing in patients with complicated and uncomplicated postoperative urolithiasis. 240 patients suffering from urolithiasis took part, who underwent surgical treatment. Patients were divided into two clinical groups: I clinical group (n = 130) – patients with a favorable course of the postoperative period of urolithiasis, II clinical group (n = 110) – patients with a complicated course of the postoperative period of urolithiasis. The control group was – 25 practically healthy persons. Lymphocyte membrane status was assessed by phase contrast microscopy. The maximum frequency of plasma membrane changes was recorded in patients with postoperative complications and amounted to 15.92 [13.20; 17.01] when evaluating initial blebbing and 21.93 [17.67; 30.45] for terminal blebbing. With a favorable course of postoperative period, patients with urolithiasis did not have statistically significant changes in the parameters of blebbing of the plasma membrane of lymphocytes.

Risk factors and outcome due to extended-spectrum β-lactamase-producing uropathogenic Escherichia coli in community-onset bloodstream infections: A ten-year cohort study in Sweden

Objective

To study clinical outcome and risk factors associated with extended-spectrum β-lactamase (ESBL)-producing uropathogenic Escherichia coli (UPEC) in community-onset bloodstream infections (CO-BSI).

Methods

This was a population-based cohort study including patients with pheno- and genotype-matched ESBL-producing E. coli and non-ESBL- E. coli in urine and blood samples collected in 2009–2018 in southeast Sweden. Seventy-seven episodes of ESBL-UPEC satisfying the inclusion criteria were matched 1:1 with 77 non-ESBL-UPEC for age, gender, and year of culture.

Results

The most common ST-type and ESBL gene was ST131 (55%), and bla_CTX-M-15 (47%), respectively. Risk factors for ESBL-UPEC were: previous genitourinary invasive procedure (RR 4.66; p = 0.005) or history of ESBL-producing E. coli (RR 12.14; p = 0.024). There was significant difference between ESBL-UPEC and non-ESBL-UPEC regarding time to microbiologically appropriate antibiotic therapy (27:15 h vs. 02:14 h; p = <0.001) and hospital days (9 vs. 5; p = <0.001), but no difference in 30-day mortality (3% vs. 3%; p = >0.999) or sepsis within 36 hours (51% vs. 62%; p = 0.623) was observed.

Conclusion

The predominant risk factors for ESBL-UPEC were history of ESBL-Ec infection and history of genitourinary invasive procedure. The overall mortality was low and the delay in appropriate antibiotic therapy did not increase the risk for 30-day mortality or risk for sepsis within 36 hours among patients infected with ESBL UPEC. However, these results must be regarded with some degree of caution due to the small sample size.

Frailty and postoperative urinary tract infection

BACKGROUND

Among older adults, postoperative urinary tract infection is associated with significant harms including increased risk of hospital readmission and perioperative mortality. While risk of urinary tract infection is known to increase with age, the independent association between frailty and postoperative urinary tract infection is unknown. In this study we used 2014-2018 data from the U.S. National Surgical Quality Improvement Program (NSQIP) to investigate whether frailty is an independent risk factor for postoperative urinary tract infection, controlling for age and other relevant confounders.

METHODS

Frailty was assessed using the modified Frailty Index. Postoperative urinary tract infection was defined as any symptomatic urinary tract infection (of the kidneys, ureters, bladder, or urethra) developing within 30 days of the operative procedure. To examine associations between frailty and other specific factors and postoperative urinary tract infection, chi squared tests, students t-tests, and logistic regression modelling were used.

RESULTS

Urinary tract infection was identified after 22,356 of 1,724,042 procedures (1.3%). In a multivariable model controlling for age and other patient and surgical characteristics, the relative odds for urinary tract infection increased significantly with increasing frailty score. For example, compared to a frailty score of 0, the relative odds for urinary tract infection for a frailty score of 3 was 1.50 (95% confidence interval 1.41, 1.60). The relative odds associated with the maximum frailty score (5) was 2.50 (95% confidence interval 1.73, 3.61).

CONCLUSIONS

Frailty is associated with postoperative urinary tract infection, independent of age. Further research should focus on the underlying mechanisms and strategies to mitigate this risk among frail adults.

The inflammatory microenvironment and the urinary microbiome in the initiation and progression of bladder cancer

Accumulating evidence suggests that chronic inflammation may play a critical role in various malignancies, including bladder cancer. This hypothesis stems in part from inflammatory cells observed in the urethral microenvironment. Chronic inflammation may drive neoplastic transformation and the progression of bladder cancer by activating a series of inflammatory molecules and signals. Recently, it has been shown that the microbiome also plays an important role in the development and progression of bladder cancer, which can be mediated through the stimulation of chronic inflammation. In effect, the urinary microbiome can play a role in establishing the inflammatory urethral microenvironment that may facilitate the development and progression of bladder cancer. In other words, chronic inflammation caused by the urinary microbiome may promote the initiation and progression of bladder cancer. Here, we provide a detailed and comprehensive account of the link between chronic inflammation, the microbiome and bladder cancer. Finally, we highlight that targeting the urinary microbiome might enable the development of strategies for bladder cancer prevention and personalized treatment.

Evaluating a hydration intervention (DRInK Up) to prevent urinary tract infection in care home residents: A mixed methods exploratory study

OBJECTIVES

To investigate potential effects and acceptability of a theoretically driven hydration intervention (DRInK-Up), on the prevalence of urinary tract infections (UTIs), falls and emergency admissions in care home residents.

METHODS

A single group pre-post evaluation design to test the DRInK-Up intervention, to increase fluid intake by 200-400ml daily. The number of UTIs, falls and emergency hospital admissions for each resident recorded over the DRInK-Up intervention period were compared to rates in the 24 weeks prior. A qualitative investigation of experiences of DRInK-Up was undertaken using focus group interviews with care home staff to determine acceptability.

RESULTS

24 care home residents took part in the intervention. There was a clinically meaningful, but non-statistically significant reduction in number of treated UTIs during the intervention period from 51 UTIs pre-DRInK-Up to 37 post-DRInK-Up (t= .498, 18df, p=0.625). The volume of fluid intake recorded was not correlated with number of UTIs (r= 0.103, p=.676). Falls reported dropped from 52 pre- to 28 post-intervention (t=3.148, df 19, p=0.005). Emergency admissions did not change. Focus group interviews suggested goal setting was uncommon and took the form of externally generated targets for fluid intake rather than negotiated goals. Barriers to increasing fluid intake included resident-related factors or arose from the care home context. A range of facilitators included verbal persuasion, praise and reward.

CONCLUSION

The DRInK-Up study provides preliminary evidence suggesting that increasing daily fluid intake by small amounts may have a potentially positive effect on number of UTIs experienced and number of falls in frail older care home residents. Further research is needed.

Are we missing hypoglycaemia? Elderly patients with insulin-treated diabetes present to primary care frequently with non-specific symptoms associated with hypoglycaemia

INTRODUCTION

We assessed if patients with known hypoglycaemia present on other occasions with non-specific symptoms associated with (but not diagnosed as) hypoglycaemia, potentially representing missed hypoglycaemia.

METHODS

335 primary care records (5/2/12-4/2/13) from patients aged >65 (79 on insulin, 85 on sulphonylureas, 121 on metformin only, 50 without diabetes) were assessed for hypoglycaemia episodes and consultations with non-specific symptoms, "hypo clues".

RESULTS

27/79(34%) insulin-treated patients had >1 documented hypoglycaemia episode, compared to 4/85(5%) sulphonylurea-treated patients, 2/121(2%) metformin-only treated patients, and none without diabetes, p<0.001. "Hypo clue" consultations were common: 1.37 consultations/patient/year in insulin-treated patients, 0.98/patient/year in sulphonylurea-treated, 0.97/patient/year in metformin only-treated, and 0.78/patient/year in non-diabetic patients, p=0.34. In insulin-treated patients with documented hypoglycaemia, 20/27(74%) attended on another occasion with a "hypo clue" symptom, compared to 21/52(40%) of those without hypoglycaemia, p=0.008. No significant difference in the other treatment groups. Nausea, falls and unsteadiness were the most discriminatory symptoms: 7/33(21%) with hypoglycaemia attended on another occasion with nausea compared to 14/302(5%) without hypoglycaemia, p=0.002; 10/33(30%) vs 36/302(12%) with falls, p=0.007; and 5/33(15%) vs 13/302(4%) with unsteadiness, p=0.023.

CONCLUSIONS

Non-specific symptoms are common in those >65 years. In insulin-treated patients at high hypoglycaemia risk, nausea, falls and unsteadiness should prompt consideration of hypoglycaemia.

Urinary tract infections in the geriatric patients

Objective

Urinary tract infections (UTI) are the second most common infection in geriatric population. This study investigated clinical findings, diagnostic approaches, complicating factors, prognosis, causative microorganisms and antimicrobial susceptibility in geriatric patients diagnosed with UTI.

Methods

A total of 140 hospitalised patients with UTIs were evaluated within three years between January 2011-January 2015 at the Eskisehir Yunus Emre State Hospital. UTI diagnosed when there were systemic and urinary signs and symptoms and a positive dipstick test and urine culture result, leukocyte and CRP like serum parameters.

Results

Among the studied patients, 41.4% had urological diseases, 20.7% had diabetes mellitus and 19.2% had neurological diseases. The most common symptoms and signs were fever, dysuria nausea/vomiting, general condition impairment, pyuria, haematuria. The laboratory values for CRP, ESR and leukocyte count were 84 mg/dL, 56 mm/s and 11.9 (10^3μL), with mean values being determined. Among patients having a urinary catheter (17.1%), 27.9% had a history of UTI, while 29.3% had been hospitalised. Escherichia coli and Klebsiella pneumoniae were the most commonly identified microorganisms. The mean duration for hospitalisation was 7.6 days, while a 5% mortality rate was observed over the course of the disease.

Conclusion

Because of the potential for serious complications and mortality, elderly patients with urinary tract infection, should receive immediate empirical treatment based on anamnesis, clinical evaluation and urinalysis and should be re-examined using results from cultures and antibiograms upon follow-up.

Emerging nanotechnology based strategies for diagnosis and therapeutics of urinary tract infections: A review

At present, various diagnostic and therapeutic approaches are available for urinary tract infections. But, still the quest for development of more rapid, accurate and reliable approach is an unending process. The pathogens, especially uropathogens are adapting to new environments and antibiotics day by day rapidly. Therefore, urinary tract infections are evolving as hectic and difficult to eradicate, increasing the economic burden to the society. The technological advances should be able to compete the adaptability characteristics of microorganisms to combat their growth in new environments and thereby preventing their infections. Nanotechnology is at present an extensively developing area of immense scientific interest since it has diverse potential applications in biomedical field. Nanotechnology may be combined with cellular therapy approaches to overcome the limitations caused by conventional therapeutics. Nanoantibiotics and drug delivery using nanotechnology are currently growing areas of research in biomedical field. Recently, various categories of antibacterial nanoparticles and nanocarriers for drug delivery have shown their potential in the treatment of infectious diseases. Nanoparticles, compared to conventional antibiotics, are more beneficial in terms of decreasing toxicity, prevailing over resistance and lessening costs. Nanoparticles present long term therapeutic effects since they are retained in body for relatively longer periods. This review focuses on recent advances in the field of nanotechnology, principally emphasizing diagnostics and therapeutics of urinary tract infections.

Overtreatment of asymptomatic bacteriuria: a qualitative study

BACKGROUND

Overtreatment of asymptomatic bacteriuria (ASB) is widespread and may result in antibiotic side-effects, excess costs to the healthcare system, and may potentially trigger antimicrobial resistance. According to international management guidelines, ASB is not an indication for antibiotic treatment (with few exceptions).

AIM

To determine reasons for using antibiotics to treat ASB in the absence of a treatment indication.

METHODS

A qualitative study was conducted at a tertiary care hospital in Switzerland during 2011. We interviewed 21 internal medicine residents and attending physicians selected by purposive sampling, using a semi-structured questionnaire. Responses were analysed in an inductive thematic content approach using dedicated software (MAXQDA(®)).

FINDINGS

In the 21 interviews, the following thematic rationales for antibiotic overtreatment of ASB were reported (in order of reporting frequency): (i) treating laboratory findings without taking the clinical picture into account (N = 17); (ii) psychological factors such as anxiety, overcautiousness, or anticipated positive impact on patient outcomes (N = 13); (iii) external pressors such as institutional culture, peer pressure, patient expectation, and excessive workload that interferes with proper decision-making (N = 9); (iv) difficulty with interpreting clinical signs and symptoms (N = 8).

CONCLUSION

In this qualitative study we identified both physician-centred factors (e.g. overcautiousness) and external pressors (e.g. excessive workload) as motivators for prescribing unnecessary antibiotics. Also, we interpreted the frequently cited practice of treating asymptomatic patients based on laboratory findings alone as lack of awareness of evidence-based best practices.

The ageing human B cell repertoire: a failure of selection?

B cells undergo a number of different developmental stages, from initial formation of their B cell receptor (BCR) genes to differentiation into antibody-secreting plasma cells. Because the BCR is vital in these differentiation steps, autoreactive and exogenous antigen binding to the BCR exert critical selection pressures to shape the B cell repertoire. Older people are more prone to infectious disease, less able to respond well to vaccination and more likely to have autoreactive antibodies. Here we review evidence of changes in B cell repertoires in older people, which may be a reflection of age-related changes in B cell selection processes.

Risk factors for catheter-associated urinary tract infection in Italian elderly

BACKGROUND

Catheter-associated urinary tract infections (CAUTIs) are the most common cause of hospital-acquired infections, especially in elderly patients. Data on CAUTIs in older persons in acute care settings are lacking, however. This study aimed to describe the epidemiology of CAUTIs and related outcomes (ie, length of stay and mortality), in patients admitted to an acute geriatric care hospital in central Italy.

METHODS

A CAUTI surveillance program was implemented from October 2011 to April 2012, according to the Centers for Disease Control and Prevention's National Healthcare Safety Network methodology.

RESULTS

A total of 2773 patients aged ≥65 years were included in the study, and 483 catheterized patients were monitored for the risk of CAUTI. The catheterization rate was 16.7% (95% confidence interval [CI], 15.3%-18.2%), and the overall CAUTI incidence rate was 14.7/1000 device-days (95% CI, 11.7-18.3/1000). Mortality was significantly higher in catheterized patients with a CAUTI compared with noncatheterized patients (19.2% vs 10.5%; P < .05). Female sex (odds ratio [OR], 1.31; 95% CI, 1.06-1.67), increasing age (≥90 years: OR, 2.76; 95% CI, 2.00-3.83), and longer hospital stay before catheter insertion (≥15 days: OR, 2.90; 95% CI, 2.20-3.83) were independent risk factors for catheterization; increasing age (>90 years: OR, 2.75; 95% CI, 1.03-7.35), and duration of hospital stay before catheter insertion (OR, 2.41; 95% CI, 1.12-5.51) were associated with CAUTIs.

CONCLUSIONS

These results underscore the importance of the proper choice of patients for catheterization, particularly in individuals aged >90 years.

Swiss Nursing Homes Human Resources Project (SHURP): protocol of an observational study

AIM

To explore the relationships among various nursing homes characteristics including work environment, careworker outcomes and resident outcomes in Swiss nursing homes.

BACKGROUND

In Switzerland, a growing number of older people live in nursing homes. Although research has addressed the issue of quality of nursing care in such facilities, few have integrated a range of interrelated factors that may influence the quality and safety of residential care. The Swiss Nursing Homes Human Resources Project will comprehensively assess key organizational factors, their interrelationships and the associations between these factors and careworker and resident outcomes.

DESIGN

Cross-sectional design.

METHODS

Three-year multi-centre study (2011-2013) including a representative sample of approximately 160 nursing homes across the three language regions in Switzerland. Survey data will come from approximately 6000 careworkers and 160 administrators. Survey questionnaires will include variables on organizational facility characteristics and resident outcomes, careworker socio-demographic and professional characteristics, the quality of their work environments, resident safety climates and careworker outcomes. Appropriate descriptive and comparative analysis will be used and multivariate and multilevel analyses will be applied to examine the relationships among the various factors including quality of the work environment, safety climate, work stressors, rationing of care, workload, careworker and resident characteristics, as well as resident and careworker outcomes.

DISCUSSION

The study results will contribute to a comprehensive understanding of the interrelationships between key organizational factors and resident/careworker outcomes and will also support planning and conducting interventions to improve quality of care concerning organizational factors affecting careworkers in daily practice.

Antimicrobial resistance and stewardship in long-term care settings

Infections and antimicrobial resistance (AMR) in long-term care facilities (LTCFs) are a public health challenge and a future infectious disease threat. More and more data show the dimension and impact of AMR and of inappropriate use of antimicrobials in this setting. Recently, the spread of carbapenemase-producing Enterobacteriaceae has provided new insights into the dangerous role the long-term care sector may play in the AMR problem in a community. Implementation of effective infection and surveillance control programs in LTCFs is challenging, due to scarce resources (personnel, expertise, diagnostic and supportive services), and no or poor coordination of medical care. However, interventions in LTCFs have been proven to be effective: inappropriate use of antibiotics for asymptomatic bacteriuria may be reduced; hand hygiene compliance may be improved; and the transmission of multidrug-resistant organisms may be halted. This paper reviews the most recent epidemiological information on this issue, providing references to valuable intervention programs.

Potential Inappropriate Treatment of Suspected Urinary Tract Infections Among Nursing Home Residents

Objective

To determine if nurse practitioners and physicians followed recommended practice guidelines prior to the initiation of antibiotics among long-term care (LTC) residents with suspected urinary tract infections (UTIs).

Methods

A retrospective review of 1-year reported cases of UTIs in 2 rural southern nursing homes.

Results

There were 175 cases of UTI reported in the 2 homes, but 6 cases were reported in error. Only 4 of the 169 remaining cases met the diagnostic criteria for UTI. The remaining 169 cases received inappropriate antibiotics. Some of these cases may represent asymptomatic bacteria rather than UTI. Problems were identified with the methods used to collect urine sample that were sent to the laboratory for culture.

Conclusion

We found that in 2 nursing homes, almost all of the reported cases of UTI did not meet the accepted diagnostic criteria. Also, there was inappropriate antibiotic therapy for most of these residents. Nurse practitioners and physicians should accurately determine the presence of UTI and document in the medical record prior to initiating antibiotic. Urine specimens should be collected using appropriate methods. Nursing homes should only report to the Centers for Medicare and Medicaid Services (CMS) those cases that meet the diagnostic criteria as a UTI.

[The challenge of infections and multiresistant bacteria among the elderly living in long-term care facilities]

Healthcare-associated infections not only affect patients in acute care hospitals but also patients in need of long-term care. As the elderly are generally most affected, the demographic change in Germany faces a range of increasing challenges in the field of infection control. The ageing process itself is accompanied by several physiological and pathological changes which may result in an increase in the risk of infectious diseases. Elderly living in long-term care facilities (LTCFs) may in addition be exposed to further risks due to their everyday life in a community, nursing care and the, to some extent, inappropriate use of antibiotics. Bacteria that have become resistant to commonly used antimicrobial agents are meanwhile prevalent in nursing homes. Caregivers often feel left alone when facing the task of achieving a balance between the need for a comfortable familiar environment and the application of infection control measures according to a resolute prevention strategy. This review aims to give an overview about the characteristics of infections among the elderly, especially with respect to long-term care.

First evidence on the validity and reliability of the Safety Organizing Scale-Nursing Home version (SOS-NH)

BACKGROUND

The Safety Organizing Scale is a valid and reliable measure on safety behaviors and practices in hospitals.

PURPOSE OF THE STUDY

This study aimed to explore the psychometric properties of the Safety Organizing Scale-Nursing Home version (SOS-NH).

DESIGN AND METHODS

In a cross-sectional analysis of staff survey data, we examined validity and reliability of the 9-item Safety SOS-NH using American Educational Research Association guidelines.

SUBJECTS AND SETTING

This substudy of a larger trial used baseline survey data collected from staff members (n = 627) in a variety of work roles in 13 nursing homes (NHs) in North Carolina and Virginia.

RESULTS

Psychometric evaluation of the SOS-NH revealed good response patterns with low average of missing values across all items (3.05%). Analyses of the SOS-NH's internal structure (eg, comparative fit indices = 0.929, standardized root mean square error of approximation = 0.045) and consistency (composite reliability = 0.94) suggested its 1-dimensionality. Significant between-facility variability, intraclass correlations, within-group agreement, and design effect confirmed appropriateness of the SOS-NH for measurement at the NH level, justifying data aggregation. The SOS-NH showed discriminate validity from one related concept: communication openness.

IMPLICATIONS

Initial evidence regarding validity and reliability of the SOS-NH supports its utility in measuring safety behaviors and practices among a wide range of NH staff members, including those with low literacy. Further psychometric evaluation should focus on testing concurrent and criterion validity, using resident outcome measures (eg, patient fall rates).

Aetiology and antibiotic resistance patterns of urinary tract infections in the elderly: a 6-month study

Urinary tract infections (UTIs) are a common cause of bacteraemia in the elderly and are associated with a high probability of hospitalization. Despite the impact of UTIs on health status and quality of life, a limited number of studies have evaluated their aetiology in this population. This study aimed to evaluate the microbial aetiology and pattern of susceptibility of bacteria causing UTIs in the elderly. For this purpose, a retrospective cohort study of elderly residents (n = 472, aged >65 years) in 14 nursing homes in Milan (Italy) and its province was performed. Globally, 393 micro-organisms from 328 samples were isolated: Escherichia coli was the most prevalent (44.8 %), followed by Proteus mirabilis (20.4 %), Providencia spp. (8.9 %), Klebsiella spp. (6.4 %) and Pseudomonas aeruginosa (4.6 %). Enterococci were the most frequently isolated Gram-positive organisms (7.4 %). Almost all Enterobacteriaceae were susceptible to nitrofurantoin, carbapenems and amikacin. Extended-spectrum β-lactamases were detected in 42.1 % of isolates. The most active antibiotics against P. aeruginosa were colistin, amikacin and piperacillin/tazobactam. All Gram-positive organisms were susceptible to glycopeptides and linezolid, and 90 % were susceptible to nitrofurantoin. Fluoroquinolones showed a limited activity against all the tested micro-organisms. Escherichia coli remains the major micro-organism responsible for UTIs in older people, although to a lesser extent than in a younger population. The high rates of resistance observed in this study make careful use of antibiotics advisable to limit further development of resistance.

Role of Uropathogenic Escherichia coli Virulence Factors in Development of Urinary Tract Infection and Kidney Damage

Uropathogenic Escherichia coli (UPEC) is a causative agent in the vast majority of urinary tract infections (UTIs), including cystitis and pyelonephritis, and infectious complications, which may result in acute renal failure in healthy individuals as well as in renal transplant patients. UPEC expresses a multitude of virulence factors to break the inertia of the mucosal barrier. In response to the breach by UPEC into the normally sterile urinary tract, host inflammatory responses are triggered leading to cytokine production, neutrophil influx, and the exfoliation of infected bladder epithelial cells. Several signaling pathways activated during UPEC infection, including the pathways known to activate the innate immune response, interact with calcium-dependent signaling pathways. Some UPEC isolates, however, might possess strategies to delay or suppress the activation of components of the innate host response in the urinary tract. Studies published in the recent past provide new information regarding how virulence factors of uropathogenic E. coli are involved in activation of the innate host response. Despite numerous host defense mechanisms, UPEC can persist within the urinary tract and may serve as a reservoir for recurrent infections and serious complications. Presentation of the molecular details of these events is essential for development of successful strategies for prevention of human UTIs and urological complications associated with UTIs.

Optimal management of urinary tract infections in older people

Urinary tract infections (UTI) occur frequently in older people. Unfortunately, UTI is commonly overdiagnosed and overtreated on the basis of nonspecific clinical signs and symptoms. The diagnosis of a UTI in the older patient requires the presence of new urinary symptoms, with or without systemic symptoms. Urinalysis is commonly used to diagnose infection in this population, however, the evidence for its use is limited. There is overwhelming evidence that asymptomatic bacteriuria should not be treated. Catheter associated urinary tract infection accounts for a significant amount of hospital-associated infection. Indwelling urinary catheters should be avoided where possible and alternatives sought. The use of narrow spectrum antimicrobial agents for urinary tract infection is advocated. Local guidelines are now widely used to reflect local resistance patterns and available agents. Guidelines need to be updated to reflect changes in antimicrobial prescribing and a move from broad to narrow spectrum antimicrobials.

The role of host factors and bacterial virulence genes in the development of pyelonephritis caused by Escherichia coli in renal transplant recipients

BACKGROUND AND OBJECTIVES

The aim of this study was to determine the role of host factors and bacterial virulence genes in the development of pyelonephritis caused by Escherichia coli in renal transplant (Tx) recipients.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A total of 328 E. coli isolates from cases of cystitis (Cys; n=239) or pyelonephritis (PN; n=89), with 169 from renal Tx recipients, were subjected to molecular analyses to identify P-fimbria subunits (PapC, PapG II, and PapGIII), G- and M-fimbriae, and aerobactin. The presence of antibiotic resistance was also determined. Parameters such as gender, age, immunosuppression regimens, causes of ESRD, kidney donor, intraoperative anastomosis, use of double J stent, trimethoprim/sulfamethoxazole (TMP/SMZ) prophylaxis, and time after Tx were evaluated.

RESULTS

A multivariate analysis showed a significant association between PN and renal Tx. In renal Tx recipients, the risk of occurrence of PN was significantly higher among males and for those no longer receiving TMP/SMZ prophylaxis. E. coli strains isolated from PN presented a lower prevalence of papGIII and lower rates of resistance to pipemidic acid. Although papGII was more prevalent in PN than in Cys, it was not independently associated with PN.

CONCLUSIONS

These findings suggested that renal Tx increases the risk for PN, and the male sex represented a host factor independently associated with risk, whereas the prophylaxis with TMP/SMZ was protective. The lack of papGIII and low resistance to first-generation quinolones were bacterial-independent risk factors for PN in Tx.

National trends in emergency department antibiotic prescribing for elders with urinary tract infection, 1996-2005

OBJECTIVES

Given reported increases in antibiotic resistance among elders with urinary tract infection (UTI) and pyelonephritis, the authors identified national rates and trends in emergency department (ED) trimethoprim-sulfamethoxazole (TMP-SMX) and fluoroquinolone prescribing for older adults from 1996 to 2005.

METHODS

This was a retrospective analysis utilizing the ED component of the 1996-2005 National Hospital Ambulatory Medical Care Survey (NHAMCS). The authors included NHAMCS ED entries aged >or=18 years with a diagnosis of UTI or pyelonephritis; pregnancy was excluded. Records were divided into 18-64 years ("adults") and >or=65 years ("elders"). Primary outcome measures were prescription of TMP-SMX monotherapy, fluoroquinolone monotherapy, and combination therapy with two or more antibiotics. Estimated visit totals and rates were calculated and trends analyzed.

RESULTS

From 1996 to 2005, there were 5 million elder ED visits for UTI or pyelonephritis. Approximately 9.4% (95% confidence interval [CI] = 7.9% to 11%) of elders received TMP-SMX monotherapy with rates decreasing over time (p-value for trend = 0.031). Overall, 35% (95% CI = 32% to 38%) of elders received fluoroquinolone monotherapy, which increased from 21% (95% CI = 14% to 27%) in 1996 to 45% (95% CI = 39% to 50%) in 2005 (p-value for trend < 0.001). Therapy with a fluoroquinolone plus a second antibiotic was used in only 4.2% (95% CI = 3.1% to 5.3%) of older patients.

CONCLUSIONS

From 1996 to 2005, TMP-SMX monotherapy in elder ED patients decreased while fluoroquinolone therapy increased. The majority of older patients receiving fluoroquinolone therapy received a single agent. Given the continued prevalence of monotherapy for elder ED patients with UTI or pyelonephritis, antibiotic resistance patterns in these patients should be better characterized to ensure institution of appropriate empiric therapy.

Infection in the elderly

Many functional, demographic, and immunologic changes associated with aging are responsible for increasing the incidence and severity of infectious diseases in the elderly. Management is complicated by age-related organ system changes. Because many of the elderly are on multiple medications for underlying illnesses, antimicrobial therapy needs to be chosen keeping drug interactions and adverse events in mind. Common infections seen in the elderly are infections of skin and soft tissue, urinary tract, respiratory tract, and gastrointestinal tract. Organized and well-funded programs to address infectious disease issues in the elderly are the only way to improve care.

Minimum Hellinger distance estimation for k-component poisson mixture with random effects

The k-component Poisson regression mixture with random effects is an effective model in describing the heterogeneity for clustered count data arising from several latent subpopulations. However, the residual maximum likelihood estimation (REML) of regression coefficients and variance component parameters tend to be unstable and may result in misleading inferences in the presence of outliers or extreme contamination. In the literature, the minimum Hellinger distance (MHD) estimation has been investigated to obtain robust estimation for finite Poisson mixtures. This article aims to develop a robust MHD estimation approach for k-component Poisson mixtures with normally distributed random effects. By applying the Gaussian quadrature technique to approximate the integrals involved in the marginal distribution, the marginal probability function of the k-component Poisson mixture with random effects can be approximated by the summation of a set of finite Poisson mixtures. Simulation study shows that the MHD estimates perform satisfactorily for data without outlying observation(s), and outperform the REML estimates when data are contaminated. Application to a data set of recurrent urinary tract infections (UTI) with random institution effects demonstrates the practical use of the robust MHD estimation method.

Incidence et caractéristiques cliniques des infections urinaires symptomatiques dans un hôpital gériatrique

OBJECTIVES AND SETTINGS: The authors had for aim to study the incidence of symptomatic urinary infections (SUTI) in elderly patients, to describe their clinical and microbiologic characteristics and first-line treatment in a geriatric hospital with 902 beds: 124 in acute care (ACF), 293 in rehabilitation and intermediate-care (RICF), and 485 in long-term-care-facilities (LTCF).

METHOD

During two months in 2003, all positive urine cultures detected by the laboratory were sent to the clinician with a questionnaire on clinical signs, diagnosis of SUTI and antibiotic treatment.

RESULTS

SUTI was diagnosed in 85 out of 204 positive urine cultures (40%). The incidence of SUTI was 1.86 per 1,000 patient-days (with rates of 2.63, 2.49, 1.41 per 1,000 patients-days for the ACF, RICF, LTCF respectively). For 51 cases (60%) there were only general symptoms, for 24 cases (28.2%) there were only urinary symptoms, and for 10 cases (11.8%) there were both. Escherichia coli and Proteus mirabilis were the main bacterial species involved in 57 and 14% respectively. E. coli strains were 59% resistant to amoxicillin, 55% resistant to amoxicillin-clavulanic acid, and 39% resistant to fluoroquinolones. The main antibiotics were fluoroquinolones, ceftriaxone, and amoxicillin-clavulanate, prescribed respectively in 52.5, 19, and 9% of the cases.

CONCLUSION

SUTI was diagnosed in only in 40% of positive urine cultures from elderly patients hospitalized in our hospital. To improve the management of SUTI in this population, we changed our recommendations for diagnosis and treatment.

Multilevel survival modelling of recurrent urinary tract infections

A multilevel survival frailty model is presented for analyzing clustered and recurrent urinary tract infections among elderly women residing in aged-care institutions. At the subject level, serial dependence is expected between recurrent events recorded on the same individual. At the cluster level, correlations of observations within the same institution are present due to the inherent residential environment and hierarchical setting. Two random components are therefore incorporated explicitly within the survival frailty model to account for the simultaneous heterogeneity and autoregressive structure. A Splus computer program is developed for the estimation of fixed effect and variance component parameters.

A score test for zero-inflation in correlated count data

To account for the preponderance of zero counts and simultaneous correlation of observations, a class of zero-inflated Poisson mixed regression models is applicable for accommodating the within-cluster dependence. In this paper, a score test for zero-inflation is developed for assessing correlated count data with excess zeros. The sampling distribution and the power of the test statistic are evaluated by simulation studies. The results show that the test statistic performs satisfactorily under a wide range of conditions. The test procedure is further illustrated using a data set on recurrent urinary tract infections.

Role of fluoroquinolones in the treatment of serious bacterial urinary tract infections

Serious urinary tract infections (UTIs) in adults--defined as acute complicated UTIs or pyelonephritis requiring initial intravenous antimicrobials and/or hospitalisation and nosocomial infections--cause significant morbidity and economic burden. In the US, UTIs are responsible for nearly 7 million outpatient physician office visits, 1 million emergency room visits and over 100 000 hospital admissions annually. Complicated UTIs often affect patients with underlying functional, metabolic or anatomical defects of the urinary tract, whereas most nosocomial UTIs (~80%) are related to short- or long-term catheterisation. Serious UTIs are often difficult to treat because infection involves a diverse array of Gram-negative and Gram-positive bacteria, coupled with increasing antimicrobial resistance in some uropathogens, and a higher rate of recurrent infections. Although Escherichia coli remains a common aetiology (< or =60%), other Enterobacteriaceae, Gram-negative bacilli (e.g. Pseudomonas aeruginosa), and Gram-positive bacteria (e.g. Staphylococcus aureus) are frequently isolated. Patients with long-term catheterisation have UTIs typically caused by organisms that produce biofilms making eradication even more difficult. Overall, aetiology and resistance patterns are not predictable for those with serious UTIs, necessitating confirmation by culture and susceptibility testing.Numerous intravenous and oral antimicrobial treatment options are available and the majority of patients with serious UTIs will need initial intravenous therapy because of the possibility of bacteraemia/sepsis or impaired gastrointestinal absorption. Many experts concur that empirical therapy for the institutionalised or hospitalised patient with a serious UTI should include an intravenous antipseudomonal agent because of an increased risk of urosepsis. While state-of-the-art treatment guidelines are lacking for these infections, targeted therapy should be initiated once susceptibility data are known. The use of targeted therapy--emphasising the "correct antibacterial spectrum" and pharmacodynamic superiority--is likely to provide important benefits (e.g. reduced morbidity and associated costs, reduced emergence of resistance). Agents commonly prescribed include aminoglycosides, beta-lactam/beta-lactamase inhibitor combinations, imipenem, advanced-generation cephalosporins and fluoroquinolones. Fluoroquinolones are often recommended when conventional agents have failed or are less desirable (e.g. toxicity/hypersensitivity concerns), or when resistance is high. Several pivotal clinical trials support the use of fluoroquinolones for serious UTIs with most experience garnered with ciprofloxacin, including a new once-daily extended-release tablet formulation.Treatment of patients with serious UTIs remains challenging. Physicians should choose empirical therapy based on patient demographics/medical history, presumed aetiology and local resistance patterns until more definitive guidelines become available.

Urinary tract infections in the frail elderly: Issues for diagnosis, treatment and prevention

Urinary tract infections (UTIs) are among the most common infections in frail elderly adults, whether they are community dwelling, live in long term care facilities (LTCFs) or are hospitalized. UTIs cause substantial morbidity and mortality in frail elderly men and women. While many major risk factors in these individuals may not be modifiable, improved attention to incontinence management, judicious use of antimicrobials and urinary catheters, and, in women, appropriate use of topical estrogen may be useful in reducing UTIs. Future strategies may also include the appropriate use of new urinary catheter technology and emerging vaccines.

Follicular dendritic cells in aging, a "bottle-neck" in the humoral immune response

Senescence leads to the appearance of atrophic follicular dendritic cells (FDCs) that trap and retain little immune complexes (IC), generate few memory B cells, and induce a reduced number of germinal centers (GC). Deficiencies in antibody responses to T cell dependent exogenous antigens such as pneumonia and influenza vaccines may reflect intrinsic FDC defects or altered FDC-B cell interactions. We recently studied antigen handling capacity and co-stimulatory activity of old FDCs and determined age-related changes in the expression or function of FcgammaRII or CR1 and 2 on FDCs. Here, we present an overview of FDC function in recall responses with known deficiencies in FDCs and GC development. Then, we review our recent work on aged FDCs and discuss age-related changes in molecular interactions between FDCs and B cells. We also discuss the causes underlying the impaired humoral immune response with respect to age-related molecular changes in FDC and B cell interactions. In vitro evidence suggests that FcgammaRII on aged FDCs is regulated abnormally and this in turn might cause the development of a defective FDC-network (reticulum) that retains few ICs, promotes ITIM signaling, prevents B cell proliferation and GC formation, and antibody production.

Recurrent urinary tract infection in women: Emerging concepts regarding etiology and treatment considerations

Recurrent urinary tract infections are caused by a combination of host factors and bacterial virulence. The patient with symptoms suggestive of recurrent urinary tract infections benefits from cultures to confirm the diagnosis of recurrent infections. The community also benefits because they allow for the tracking of resistant patterns. Once a patient has been diagnosed with recurrent urinary tract infections, there are a number of treatment choices in terms of initial treatment and prophylaxis. Treatment of the acute infection should follow the published guidelines of the Infectious Diseases Society of America taking into account local patterns of resistance. Younger patients can prevent infections by avoiding spermicides and taking cranberry tablets. Older patients may prevent infections by using estrogen and emptying their bladders fully. All patients may benefit from using antibiotic prophylaxis.

Ageing and infection

Average life expectancy throughout developed countries has rapidly increased during the latter half of the 20th century and geriatric infectious diseases have become an increasingly important issue. Infections in the elderly are not only more frequent and more severe, but they also have distinct features with respect to clinical presentation, laboratory results, microbial epidemiology, treatment, and infection control. Reasons for increased susceptibility include epidemiological elements, immunosenescence, and malnutrition, as well as a large number of age-associated physiological and anatomical alterations. Moreover, ageing may be the cause of infection but infection can also be the cause of ageing. Mechanisms may include enhanced inflammation, pathogen-dependent tissue destruction, or accelerated cellular ageing through increased turnover. In most instances, treatment of infection leads to a satisfactory outcome in the elderly. However, in palliative care situations and in patients with terminal dementia, the decision whether or not to treat an infectious disease is becoming a difficult ethical issue.