Prevalence and Outcomes of Multi-Drug Resistant Blood Stream Infections Among Nursing Home Residents Admitted to an Acute Care Hospital

The pathogenicity and virulence of the opportunistic pathogen Staphylococcus epidermidis

The pervasive presence of Staphylococcus epidermidis and other coagulase-negative staphylococci on the skin and mucous membranes has long underpinned a casual disregard for the infection risk that these organisms pose to vulnerable patients in healthcare settings. Prior to the recognition of biofilm as an important virulence determinant in S. epidermidis, isolation of this microorganism in diagnostic specimens was often overlooked as clinically insignificant with potential delays in diagnosis and onset of appropriate treatment, contributing to the establishment of chronic infection and increased morbidity or mortality. While impressive progress has been made in our understanding of biofilm mechanisms in this important opportunistic pathogen, research into other virulence determinants has lagged S. aureus. In this review, the broader virulence potential of S. epidermidis including biofilm, toxins, proteases, immune evasion strategies and antibiotic resistance mechanisms is surveyed, together with current and future approaches for improved therapeutic interventions.

Epidemiology, Clinical, and Microbiological Characteristics of Multidrug-Resistant Gram-Negative Bacteremia in Qatar

Antimicrobial resistance is a global healthcare threat with significant clinical and economic consequences peaking at secondary and tertiary care hospitals where multidrug-resistant Gram-negative bacteria (MDR GNB) lead to poor outcomes. A prospective study was conducted between January and December 2019 for all invasive bloodstream infections (BSIs) secondary to MDR GNB in Qatar identified during routine microbiological service to examine their clinical, microbiological, and genomic characteristics. Out of 3238 episodes of GNB BSIs, the prevalence of MDR GNB was 13% (429/3238). The predominant MDR pathogens were Escherichia coli (62.7%), Klebsiella pneumoniae (20.4%), Salmonella species (6.6%), and Pseudomonas aeruginosa (5.3%), while out of 245 clinically evaluated patients, the majority were adult males, with the elderly constituting almost one-third of the cohort and with highest observed risk for prolonged hospital stays. The risk factors identified included multiple comorbidities, recent healthcare contact, previous antimicrobial therapy, and admission to critical care. The in-hospital mortality rate was recorded at 25.7%, associated with multiple comorbidities, admission to critical care, and the acquisition of MDR Pseudomonas aeruginosa. Resistant pathogens demonstrated high levels of antimicrobial resistance but noticeable susceptibility to amikacin and carbapenems. Genomic analysis revealed that Escherichia coli ST131 and Salmonella enterica ST1 were the predominant clones not observed with other pathogens.

Accelerating Detection and Intervention for Sepsis in Skilled Nursing Facilities Using a Sepsis Pathway

BACKGROUND

Early detection of sepsis decreases mortality in hospitals, but recognition of sepsis is often delayed in skilled nursing facilities (SNFs).

LOCAL PROBLEM

A local SNF in the northeastern United States sought to use a standardized sepsis pathway to prevent hospital readmissions due to sepsis.

METHODS

A pre-/postimplementation design was used for this project. Outcome measures included sepsis detection and treatment, length of stay in the SNF, sepsis-related hospital transfer rate, mortality rate, and predictors of clinical outcomes.

INTERVENTIONS

A SNF sepsis pathway was developed based on current sepsis detection tools. The pathway incorporated a sepsis screening tool and a sepsis bundle. Implementation of the pathway involved education of nurses and certified nursing assistants on the pathway.

RESULTS

A total of 178 patients were included in data analysis (81 preimplementation and 97 implementation). Sepsis recognition increased from 56% to 86% ( P < .001), and sepsis-related hospital transfers decreased from 68% to 44% ( P = .07). Laboratory testing for lactate, white blood cell count, and blood cultures increased, and sepsis intervention rates significantly improved ( P < .001).

CONCLUSIONS

Implementing a modified SNF sepsis pathway accelerated identification of sepsis and improved clinical outcomes.

Evaluation of the Recommended 30 cc/kg Fluid Dose for Patients With Septic Shock and Hypoperfusion With Lactate Greater Than 4 mmol/L

The Surviving Sepsis Campaign Guidelines recommend fluid administration of 30 cc/kg ideal body weight (IBW) for patients with sepsis and lactate greater than 4 mmol/L within 3 hours of identification. In this study, we explore the impact of fluid dose on lactate normalization, treatment cost, length of stay, and mortality in patients with lactate greater than 4.

DESIGN

Multicenter retrospective observational study.

SETTING

Eight-hospital urban healthcare system in Northeastern United States.

PATIENTS

Patients with sepsis, initial lactate value greater than 4 mmol/L, and received appropriate antibiotics within 3 hours.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We stratified patients into five groups based on the dose of fluid administered within 3 hours after sepsis identification. The groupings were less than 15 cc/kg IBW, 15.1-25 cc/kg IBW, 25.1-35 cc/kg IBW, 35.1-50 cc/kg IBW, and greater than 50 cc/kg IBW. We used the group that received a fluid dose of 25.1-35 cc/kg IBW, as a reference group. The mean age was 66 years, and 56% were male. Three hundred seventy-one (25%) received less than 15 cc/kg of IBW of crystalloid fluid, 278 (17%) received 15-25 cc/kg of IBW, 316 (21%) received 25.1-35 cc/kg of IBW, 319 (21%) received 35.1-50 cc/kg of IBW, and 207 (14%) received greater than 50 cc/kg of IBW. After multilinear regression, there was no significant difference in lactate normalization between the reference group and any of the other fluid groups. We also found no statistically significant difference in the observed/expected cost, or observed/expected length of stay, between the reference group and any of the other fluid groups. Mortality was higher among patients who received greater than 50 cc/kg IBW when compared to the recommended dose.

CONCLUSIONS

In patients with sepsis and lactate value greater than 4 mmol/L, high or low fluid doses were not associated with better lactate clearance or patient outcomes. Greater than 50 cc/kg IBW dose of fluids within 3 hours is associated with higher mortality.

Phenotypic and genotypic antibiotic susceptibility profiles of Gram-negative bacteria isolated from bloodstream infections at a referral hospital, Lusaka, Zambia

Bloodstream infections (BSI) caused by antimicrobial-resistant (AMR) Gram-negative bacteria (GNB) are a significant cause of morbidity and mortality. Third-generation cephalosporins (3GCs) have been used as empiric treatment for BSI and other invasive infections for years; however, their overuse could promote the emergence of extended-spectrum beta-lactamases (ESBLs). Thus, this study aimed to determine the epidemiological, clinical and microbiological features and the effects of antimicrobial resistance on the outcomes of BSIs at a referral hospital in Lusaka, Zambia. This was a six-month prospective facility-based study undertaken at a referral hospital in Lusaka, Zambia. As part of the routine diagnosis and patient care, blood samples for bacteriological culture were collected from patients presenting with fever and processed for pathogen identification and antimicrobial susceptibility testing using the VITEK 2 Compact instrument. ESBLs and plasmid-mediated quinolone resistance (PMQR) associated genes were determined using the polymerase chain reaction method. Patient information was collected using a structured data collection sheet and entered in CSpro 7.6. Data were analysed in WHOnet and STATA version 14. A total of 88 GNB were isolated, of which 76% were Enterobacterales, 14% Acinetobacter baumannii and 8% Pseudomonas aeruginosa. Resistance to third and fourth-generation cephalosporins was 75% and 32%, respectively. Noteworthy was the high prevalence (68%) of inappropriate empirical treatment, carbapenem resistance (7%), multi-drug resistance (83%) and ESBL-producers (76%). In comparison to E. coli as a causative agent of BSI, the odds of death were significantly higher among patients infected with Acinetobacter baumannii (OR = 3.8). The odds of death were also higher in patients that received 3GCs as empiric treatment than in those that received 4GCs or other (none cephalosporin) treatment options. Structured surveillance, yearly antibiogram updates, improved infection control and a well functional antimicrobial stewardship (AMS) program, are of utmost importance in improving appropriate antimicrobial treatment selection and favourable patient outcomes.

Nursing home-associated bloodstream infection: A scoping review

OBJECTIVE

To update a 2005 review of nursing home-associated bloodstream infection (NHABSI) regarding sources, organisms, antibiotic resistance, and outcome.

METHODS

A scoping review of studies of NHABSI identified by searching Google Scholar and Medline with OVID for the period January 1, 2004, to June 30, 2021, was conducted.

RESULTS

Overall, 6 studies of NHABSI were identified. Only 1 study was conducted with residents in North American facilities whereas in the 2005 review all studies were conducted in North America. Escherichia coli was the most common blood isolate, the urinary tract was the most common source of NHABSI; and the case-fatality rates ranged from 21% to 28%. These findings were comparable to those in the 2005 review. However, the proportion of NHABSI episodes due to antibiotic-resistant organisms increased substantially compared to the 2005 review. The most common antibiotic-resistant organisms were extended-spectrum β-lactamase-producing E. coli and Klebsiella spp. The 2 studies that evaluated the relationship between appropriate empiric antibiotic therapy and outcome came to different conclusions.

CONCLUSIONS

The only major difference between the 2 reviews in the epidemiology of NHABSI was the marked increase in antibiotic resistance among blood isolates. Despite the increased antibiotic resistance, the case fatality rates in the current review were comparable to those reported in the 2005 review. However, the impact of appropriate empiric antibiotic therapy on outcome of NHABSI remains unclear.

Mortality in Thai Nursing Homes Based on Antimicrobial-Resistant Enterobacterales Carriage and COVID-19 Lockdown Timing: A Prospective Cohort Study

Antimicrobial-resistant Enterobacterales carriage and the coronavirus disease 2019 (COVID-19) lockdown measures may impact the incidence all-cause mortality rate among nursing home residents. To determine the all-cause mortality rate in the presence/absence of antimicrobial-resistant Enterobacterales carriage and the incidence all-cause mortality rate before and during COVID-19 pandemic lockdown, this prospective closed-cohort study was conducted at various types of nursing homes in Bangkok, Thailand, from June 2020 to December 2021. The elderly residents included 142 participants (aged ≥60 years) living in nursing homes ≥3 months, who did not have terminal illnesses. Time-to-event analyses with Cox proportional hazards models and stratified log-rank tests were used. The all-cause mortality rate was 18%, and the incidence all-cause mortality rate was 0.59/1000 person-days in residents who had antimicrobial-resistant Enterobacterales carriage at baseline. Meanwhile, the incidence all-cause mortality rate among noncarriage was 0.17/1000 person-days. The mortality incidence rate of carriage was three times higher than residents who were noncarriage without statistical significance (HR 3.2; 95% CI 0.74, 13.83). Residents in nonprofit nursing homes had a higher mortality rate than those in for-profit nursing homes (OR 9.24; 95% CI 2.14, 39.86). The incidence mortality rate during and before lockdown were 0.62 and 0.30, respectively. Effective infection-control policies akin to hospital-based systems should be endorsed in all types of nursing homes. To limit the interruption of long-term chronic care, COVID-19 prevention should be individualized to nursing homes.

Rectal Colonization by Drug Resistant Bacteria in Nursing Home Residents in Crete, Greece

(1) Background: In an area with a high prevalence of multi-drug resistant Gram-negative bacteria (MDR-GNB), we investigated the colonization of nursing home residents by such organisms. (2) Methods: A point prevalence study was performed in six nursing homes of the Heraklion area on the island of Crete. A rectal swab was taken and cultured from each participant, while additional risk factors such as recent hospitalization or antimicrobial usage were recorded and evaluated. (3) Results: A total of 137 nursing home residents were included in the study. Their mean age was 82.1 years and 19.7% were males. In total, cultures yielded 255 GNB; E. coli, K. pneumoniae and P. aeruginosa were the most common. Among the microorganisms cultured, 17.6% had the extended-spectrum beta-lactamase phenotype, while 18% were MDR. A statistically significant association was found between recent antimicrobial use and colonization by MDR-GNB; (4) Conclusions: Colonization by MDR-GNB was found to be highly prevalent in nursing home residents. Recent antimicrobial use was associated with MDR-GNB carriage.