Association of the Dundee severity classification with mortality, length of stay and readmission in adult inpatients with cellulitis

Impact of first-line dalbavancin for cellulitis on hospital admissions and costs: A case series

BACKGROUND

Many patients with cellulitis are treated with oral antibiotics as outpatients, but some require hospital admission for intravenous antibiotics. During the coronavirus disease 2019 pandemic, Betsi Cadwaladr University Health Board in Wales approved use of dalbavancin as first-line intravenous antibiotic from April to December 2020 to facilitate early discharge and prevent hospital admission.

OBJECTIVES

To report cost savings and admission avoidance through first-line intravenous use of dalbavancin for cellulitis in one health board in Wales.

PATIENTS AND METHODS

Patients with cellulitis who presented to the emergency department or medical assessment unit at Betsi Cadwaladr University Health Board's two hospitals between April and December 2020 were identified for treatment with dalbavancin, because they had not responded to oral antibiotics or their initial presentation warranted intravenous antibiotics. Patients received 1500 mg dalbavancin by intravenous infusion according to prescribing information and were sent home without being admitted. Outcomes were admission within 30 d of dalbavancin and cost savings from avoiding admission.

RESULTS

31 patients were treated with dalbavancin for cellulitis in the emergency department or medical assessment unit. No patient was admitted within 30 d of receiving dalbavancin. Use of dalbavancin is estimated to have saved 248 bed-days over the study period, with an estimated saving of $120,444.23 based on avoidance of admission. The cost of dalbavancin for these 31 patients was $69,959.08, giving an overall cost saving of $50,485.15 ($1529.95 per patient).

CONCLUSIONS

Prescribing dalbavancin as first-line intravenous antibiotic for cellulitis prevents admission, saving bed-days and admission-related costs.

Development and external validation of machine learning-based models to predict patients with cellulitis developing sepsis during hospitalisation

OBJECTIVE

Cellulitis is the most common cause of skin-related hospitalisations, and the mortality of patients with sepsis remains high. Some stratification models have been developed, but their performance in external validation has been unsatisfactory. This study was designed to develop and compare different models for predicting patients with cellulitis developing sepsis during hospitalisation.

DESIGN

This is a retrospective cohort study.

SETTING

This study included both the development and the external-validation phases from two independent large cohorts internationally.

PARTICIPANTS AND METHODS

A total of 6695 patients with cellulitis in the Medical Information Mart for Intensive care (MIMIC)-IV database were used to develop models with different machine-learning algorithms. The best models were selected and then externally validated in 2506 patients with cellulitis from the YiduCloud database of our university. The performances and robustness of selected models were further compared in the external-validation group by area under the curve (AUC), diagnostic accuracy, sensitivity, specificity and diagnostic OR.

PRIMARY OUTCOME MEASURES

The primary outcome of interest in this study was the development based on the Sepsis-3.0 criteria during hospitalisation.

RESULTS

Patient characteristics were significantly different between the two groups. In internal validation, XGBoost was the best model, with an AUC of 0.780, and AdaBoost was the worst model, with an AUC of 0.585. In external validation, the AUC of the artificial neural network (ANN) model was the highest, 0.830, while the AUC of the logistic regression (LR) model was the lowest, 0.792. The AUC values changed less in the boosting and ANN models than in the LR model when variables were deleted.

CONCLUSIONS

Boosting and neural network models performed slightly better than the LR model and were more robust in complex clinical situations. The results could provide a tool for clinicians to detect hospitalised patients with cellulitis developing sepsis early.

Current challenges in acute bacterial skin infection management

PURPOSE OF REVIEW

There are aspects of skin and soft tissue infections (SSTIs) that remain unresolved, such as current numbers, classification criteria, how best to define severity and predict the outcome, what diagnostic tests to perform, what new treatment options are available, or what the duration of antibiotic treatment should be. We have reviewed the literature over the last 18 months to clarify these issues and provide our opinion.

RECENT FINDINGS

SSTIs are common and among the top 10 most frequent infections worldwide. They represent a burden on the healthcare system and have a major impact on the quality of life of patients. Regarding classification, the Infectious Diseases Society of America (IDSA) provides a practical guide that distinguishes between uncomplicated and complicated infections, acute and chronic wound infections, and necrotising and nonnecrotizing infections based on skin extension and tissue necrosis. With new microbiological and imaging diagnostic techniques, SSTIs can now be better diagnosed. New PCR techniques are available, and mass spectrometry can be applied to samples collected in liquid transport media. Moreover, new treatment methods such as photodynamic therapy, reactive oxygen, and phages are emerging. SSTI patients can be treated with shorter antibiotic courses if they receive an active drug with good tissue penetration. Antibiotic treatment in necrotizing infections can be shortened to 48 h after the last debridement.

SUMMARY

SSTIs remain a challenge regarding rapid and accurate diagnosis and clinical management.

Diagnostic methods for the confirmation of non-purulent cellulitis: a review

Cellulitis is the most common cause for skin disease hospitalization with costs totaling over $7 billion. It can be challenging to diagnose due to clinical similarities with other inflammatory conditions and the lack of a gold-standard diagnostic test. This article reviews the different testing methods for the diagnosis of non-purulent cellulitis based on three categories (1) clinical scoring assessments, (2) in vivo imaging techniques, and (3) laboratory assessments.

Assessing Empiric Antimicrobial Therapy With the Modified Dundee Classification for Nonpurulent Skin and Soft Tissue Infections in a Community Hospital System

Background

The modified Dundee classification has recently been validated in various studies for nonpurulent skin and soft tissue infections. This has yet to be applied in the United States and within community hospital settings to optimize antimicrobial stewardship and ultimately patient care.

Methods

A retrospective, descriptive analysis was performed of 120 adult patients admitted to St. Joseph's/Candler Health System for nonpurulent skin and soft tissue infections between January 2020 and September 2021. Patients were classified into their modified Dundee classes, and frequencies of concordance of their empiric antimicrobial regimens with this classification scheme in the emergency department and inpatient settings were compared, along with possible effect modifiers and possible exploratory measures associated with concordance.

Results

Concordance with the modified Dundee classification for the emergency department and inpatient regimens was 10% and 15%, respectively, with broad-spectrum antibiotic use and concordance positively associated with illness severity. Due to substantial broad-spectrum antibiotic use, possible effect modifiers associated with concordance were unable to be validated, and overall no statistically significant differences among exploratory analyses across classification status were observed.

Conclusions

The modified Dundee classification can help identify gaps in antimicrobial stewardship and excessive broad-spectrum antimicrobial usage toward optimizing patient care.

A Multicomponent Intervention to Reduce Readmissions Among People With HIV

BACKGROUND

Hospital readmissions are common, costly, and potentially preventable, including among people with HIV (PWH). We present the results of an evaluation of a multicomponent intervention aimed at reducing 30-day readmissions among PWH.

METHODS

Demographic, socioeconomic, and clinical variables were collected from the electronic health records of PWH or those with cellulitis (control group) hospitalized at an urban safety-net hospital before and after (from September 2012 to December 2016) the implementation of a multidisciplinary HIV transitional care team. After October 2014, hospitalized PWH could receive a medical HIV consultation ± a transitional care nurse intervention. The primary outcome was readmission to any hospital within 30 days of discharge. Multivariate logistic regression and propensity score analyses were conducted to compare readmissions before and after intervention implementation in PWH and people with cellulitis.

RESULTS

Overall, among PWH, 329 of the 2049 (16.1%) readmissions occurred before and 329 of the 2023 (16.3%) occurred after the transitional care team intervention. After including clinical and social predictors, the adjusted odds ratio of 30-day readmissions for postintervention for PWH was 0.81 (95% confidence interval: 0.66 to 0.99, P= 0.04), whereas little reduction was identified for those with cellulitis (adjusted odds ratio 0.91 (95% confidence interval: 0.81 to 1.02, P= 0.10). A dose-response effect was not observed for receipt of different HIV intervention components.

CONCLUSIONS

A multicomponent intervention reduced the adjusted risk of 30-day readmissions in PWH, although no dose-response effect was detected. Additional efforts are needed to reduce overall hospitalizations and readmissions among PWH including increasing HIV prevention, early diagnosis and engagement in care, and expanding the availability and spectrum of transitional care services.

The impact of the Auckland cellulitis pathway on length of hospital stay, mortality readmission rate, and antibiotic stewardship

BACKGROUND

The Dundee classification of cellulitis severity, previously shown to predict disease outcomes, provides an opportunity to improve the management of patients with cellulitis.

METHODS

We developed and implemented a pathway to guide the management of adults with cellulitis based on their Dundee severity class, and measured its effect on patient outcomes. We compared the outcomes in patients admitted to Auckland City Hospital (ACH) between July 2014 and July 2015 (the baseline cohort) with those in patients admitted between June 2017 and June 2018 (the intervention cohort).

RESULTS

The median length of stay was shorter in the intervention cohort (0.7 days, IQR 0.1 to 3.0 days) than in the baseline cohort (1.8 days, IQR 0.1 to 4.4 days; P<0.001). The 30 day mortality rate declined from 1.8% (19/1092) in the baseline cohort to 0.7% (10/1362; P=0.02) in the intervention cohort. The 30 day cellulitis readmission rate increased from 6% in the baseline cohort to 11% (P<0.001) in the intervention cohort. Adherence to the ACH cellulitis antibiotic guideline improved from 38% to 48% (P<0.01) and was independently associated with reduced length of stay.

CONCLUSIONS

The implementation of the Auckland cellulitis pathway, readily generalizable to other settings, improved the outcomes in patients with cellulitis, and resulted in an annual saving of approximately 1,000 bed days.

A Multicenter Evaluation of Vancomycin-Associated Acute Kidney Injury in Hospitalized Patients with Acute Bacterial Skin and Skin Structure Infections

Background

We sought to determine the real-world incidence of and risk factors for vancomycin-associated acute kidney injury (V-AKI) in hospitalized adults with acute bacterial skin and skin structure infections (ABSSSI).

Methods

Retrospective, observational, cohort study at ten U.S. medical centers between 2015 and 2019. Hospitalized patients treated with vancomycin (≥ 72 h) for ABSSSI and ≥ one baseline AKI risk factor were eligible. Patients with end-stage kidney disease, on renal replacement therapy or AKI at baseline, were excluded. The primary outcome was V-AKI by the vancomycin guidelines criteria.

Results

In total, 415 patients were included. V-AKI occurred in 39 (9.4%) patients. Independent risk factors for V-AKI were: chronic alcohol abuse (aOR 4.710, 95% CI 1.929–11.499), no medical insurance (aOR 3.451, 95% CI 1.310–9.090), ICU residence (aOR 4.398, 95% CI 1.676–11.541), Gram-negative coverage (aOR 2.926, 95% CI 1.158–7.392) and vancomycin duration (aOR 1.143, 95% CI 1.037–1.260). Based on infection severity and comorbidities, 34.7% of patients were candidates for oral antibiotics at baseline and 39.3% had non-purulent cellulitis which could have been more appropriately treated with a beta-lactam. Patients with V-AKI had significantly longer hospital lengths of stay (9 vs. 6 days, p = 0.001), higher 30-day readmission rates (30.8 vs. 9.0%, p < 0.001) and increased all-cause 30-day mortality (5.1 vs. 0.3%, p = 0.024)

Conclusions

V-AKI occurred in approximately one in ten ABSSSI patients and may be largely prevented by preferential use of oral antibiotics whenever possible, using beta-lactams for non-purulent cellulitis and limiting durations of vancomycin therapy.

Electronic supplementary material

The online version of this article (10.1007/s40121-019-00278-1) contains supplementary material, which is available to authorized users.