Inpatient treatment patterns, outcomes, and costs of skin and skin structure infections because of Staphylococcus aureus

Pedicled Flaps for High-Risk Open Vascular Procedures of the Lower Extremity: An Analysis of The National Surgical Quality Improvement Project Database

BACKGROUND

 Use of pedicled flaps in vascular procedures is associated with decreased infection and wound breakdown. We evaluated the risk profile and postoperative complications associated with lower extremity open vascular procedures with and without pedicled flaps.

METHODS

 The American College of Surgeons National Surgical Quality Improvement Program database (2010-2020) was queried for Current Procedural Terminology codes representing lower extremity open vascular procedures, including trunk and lower extremity pedicled flaps. Flap patients were compared with a randomized control group without flaps (1:3 cases to controls). Univariate and multivariate analyses were performed.

RESULTS

 We identified 132,934 adults who underwent lower extremity open vascular procedures. Concurrent pedicled flaps were rare (0.7%), and patients undergoing bypass procedures were more likely to receive a flap than nonbypass patients (69 vs. 64%, p < 0.0001). Flap patients had greater comorbidities. On univariate analysis, flap patients were more likely to experience wound (p = 0.0026), mild systemic (p < 0.0001), severe systemic (p = 0.0452), and all-cause complications (p < 0.0001). After adjusting for factors clinically suspected to be associated with increased risk (gender, body mass index, procedure type, American Society of Anesthesiologists classification, functional status, diabetes, smoking, and albumin < 3.5 mg/dL), wound (p = 0.096) and severe systemic complications (p = 0.0719) were no longer significantly associated with flap patients.

CONCLUSION

 Lower extremity vascular procedures are associated with a high risk of complications. Use of pedicled flaps remains uncommon and more often performed in patients with greater comorbid disease. However, after risk adjustment, use of a pedicled flap in high-risk patients may be associated with lower than expected wound and severe systemic complications.

Out Of Hospital And In Hospital Management Of Cellulitis Requiring Intravenous Therapy

Background

Cellulitis requiring intravenous therapy can be managed via out of hospital programs, but a high number of patients are still admitted to hospital.

Objective

We aimed to review the clinical features, management and outcomes of patients with cellulitis requiring intravenous therapy in a Hospital in the Home (HITH) program compared to patients who are admitted to hospital.

Methods

A prospective cohort study of patients with limb cellulitis requiring intravenous antibiotics was conducted at a metropolitan principal referral hospital.

Results

A total of 100 patients out of 113 eligible patients were recruited. Forty-eight were treated entirely in hospital and 52 were treated entirely or partially via HITH. Patients treated in hospital were older (mean 69.2 vs 56.7 years, p<0.001), less mobile, have more comorbidities (Charlson Comorbidity Index mean 2.2 vs 1.2, P=0.005) and more associated active illness. All patients with Eron Class III were admitted to hospital. Patients treated in hospital had a higher incidence of acute renal failure (27.1% vs 3.8%, p=0.001), nosocomial infection (10.4% vs 0.0%, P=0.023), and a higher 28-day hospital readmission rate (10.4% vs 0.0%, P=0.023).

Conclusion

Approximately half of the patients who require intravenous therapy can be treated via an out of hospital program. Patients admitted to hospital were more unwell and more likely to suffer complications. The presence of comorbid illness does not necessarily exclude participation in HITH and careful selection is essential to ensure safe outcomes.

Age-based health and economic burden of skin and soft tissue infections in the United States, 2000 and 2012

OBJECTIVE

The aim of this study was to compare the incidence of skin and soft tissue infections (SSTIs) across healthcare settings and analyze direct healthcare expenditures related to SSTIs in 2000 and 2012 in the United States.

METHODS

We performed a retrospective, cross-sectional analysis of nationally representative data from the Medical Expenditure Panel Surveys. Population-based incidence rates were examined for all healthcare settings that include inpatient visits, emergency department visits and ambulatory visits for SSTIs. The direct costs of healthcare services utilization were reported. Population-based prescribing rates for each antimicrobial class during ambulatory visits were compared.

RESULTS

A total of 2.4 million patients experienced an SSTI in 2000 compared to 3.3 million in 2012 (40% increase). From 2000 to 2012, the incidence of patients with at least one hospital visit for SSTIs increased 22%, ambulatory care visits increased 30%, and emergency department visits increased 40%. The incidence of SSTIs in children and adolescents declined 50% (from 150 to 76 per 10,000 person; RR = 0.51, 95% CI: 0.38-0.67; p<0.001) whereas SSTIs in older adults (> 65 years of age) increased almost 2-fold (from 67 to 130 per 10,000 person; RR = 1.94, 95% CI: 1.44-2.61; p<0.001). The annual incidence of SSTI in adults did not change significantly from 2000 to 2012 (from 84 to 81 per 10,000 person; RR = 0.96, 95% CI: 0.71-1.31; p = 0.41). The total estimated direct healthcare costs of SSTIs increased 3-fold from $4.8 billion in 2000 to $15.0 billion in 2012, largely driven by an 8-fold increase in ambulatory expenditures for SSTIs. Total population-based antimicrobial prescription rates for SSTIs increased 4-fold from 2000 to 2012 (from 59.5 to 250.4 per 10,000 person).

CONCLUSIONS

The highest healthcare utilization for SSTI treatment occurred in the ambulatory care setting and also accounted for the largest increase in overall direct expenditures from 2000 to 2012.

Optimizing skin and skin structure infection outcomes: considerations of cost of care

INTRODUCTION

Skin and skin structure infections (SSSIs) refer to a collection of clinical infectious syndromes involving layers of skin and associated soft tissues. Although associated with less morbidity and mortality than other common skin infections, SSSIs represent a significant increasing source of healthcare expense, with a prevalence of 500 episodes per 10,000 patient-years in the United States resulting in burdening health care systems, of approximately $6 billion annually.

AREAS COVERED

Opportunities to reduce costs of care associated with SSSI are highlighted, including transitions of care and avoiding unnecessary hospital admissions. Moreover, we reviewed new antibiotics (e.g. single dose glycopeptides), and the impact of consulting specialists in the emergency department on SSSI treatment outcomes.

EXPERT COMMENTARY

New healthcare models and payment strategies combined with new therapeutics are challenging norms of care. Newer drugs to treat skin infections can move a substantive percent of patients previously admitted to hospital care to the outpatient setting. Additionally, patients can be managed with oral or one time intravenous regimens, improving the likelihood of patient adherence and satisfaction. These variables need to be weighed against added acquisition costs and the development of thoughtful algorithms is needed to direct care and optimize treatment, cost, and patient satisfaction.

Clinical characteristics associated with days to discharge among patients admitted with a primary diagnosis of lower limb cellulitis

BACKGROUND

Clinicians have limited ability to classify risk of prolonged hospitalization among patients with lower limb cellulitis.

OBJECTIVE

We sought to identify characteristics associated with days to discharge and prolonged stay.

METHODS

We conducted retrospective cohort analysis including patients admitted with a primary diagnosis of lower limb cellulitis at community and tertiary hospitals.

RESULTS

There were 4224 admissions for lower limb cellulitis among 3692 patients. Mean age of the cohort was 64.4 years. Frequencies of tobacco smoking, obesity, and diabetes mellitus were 25.1%, 44.9%, and 19.3%, respectively. Patients having decreased likelihood of discharge included those with the following: 10-year age increments 0.90 (95% confidence interval [CI] 0.88-0.92), obesity 0.90 (95% CI 0.83-0.97), diabetes mellitus 0.90 (95% CI 0.82-0.98), tachycardia 0.76 (95% CI 0.67-0.85), hypotension 0.77 (95% CI 0.65-0.90), leukocytosis 0.86 (95% CI 0.79-0.93), neutrophilia 0.80 (95% CI 0.73-0.87), elevated serum creatinine 0.74 (95% CI 0.68-0.81), and low serum bicarbonate 0.84 (95% CI 0.75-0.95).

LIMITATIONS

This analysis is retrospective and based on coded data. Unknown confounding variables may also influence prolonged stay.

CONCLUSIONS

Patients with lower limb cellulitis and prolonged stay have a number of clinical characteristics which may be used to classify risk for prolonged stay.

Patient and Surgical Factors Contributing to Perioperative Infection in Complex Lower Extremity Trauma

Infections in the traumatized lower extremity are a significant source of morbidity and expense. Outcomes after vascularized soft tissue reconstruction were analyzed to determine impact on infection rates. A retrospective review of a prospectively maintained database was performed, including 114 trauma patients requiring soft tissue reconstruction of lower extremity injuries at an urban Level I tertiary referral center from 2008 to 2015. Patient characteristics and perioperative outcomes were analyzed. After trauma, 39 (34.2%) patients developed wound infections, of which 74.4 per cent of infections occurred before soft tissue coverage. Isolated lower extremity injury yielded a 4-fold increase in the incidence of infection. Infection rates doubled in patients who smoked, sustained a fall, had a proximal third of the lower leg wound, or underwent external fixation. Comorbid diabetes, underlying fracture, and wound size were not predictive of infection. Overall, there was a 97.4 per cent rate of limb salvage after soft tissue reconstruction. In patients with infection before soft tissue reconstruction, a salvage rate of 96.6 per cent was achieved. Soft tissue reconstruction in the traumatized and infected lower extremity resulted in high limb salvage success rates, demonstrating vascularized tissue transfer in lower extremity injuries is effective in treating lower extremity infection.

Examination of hospital length of stay in Canada among patients with acute bacterial skin and skin structure infection caused by methicillin-resistant Staphylococcus aureus

PURPOSE

Skin infections, particularly those caused by resistant pathogens, represent a clinical burden. Hospitalization associated with acute bacterial skin and skin structure infections (ABSSSI) caused by methicillin-resistant Staphylococcus aureus (MRSA) is a major contributor to the economic burden of the disease. This study was conducted to provide current, real-world data on hospitalization patterns for patients with ABSSSI caused by MRSA across multiple geographic regions in Canada.

PATIENTS AND METHODS

This retrospective cohort study evaluated length of stay (LOS) for hospitalized patients with ABSSSI due to MRSA diagnosis across four Canadian geographic regions using the Discharge Abstract Database. Patients with ICD-10-CA diagnosis consistent with ABSSSI caused by MRSA between January 2008 and December 2014 were selected and assigned a primary or secondary diagnosis based on a prespecified ICD-10-CA code algorithm.

RESULTS

Among 6,719 patients, 3,273 (48.7%) and 3,446 (51.3%) had a primary and secondary diagnosis, respectively. Among patients with a primary or secondary diagnosis, the cellulitis/erysipelas subtype was most common. The majority of patients presented with 0 or 1 comorbid condition; the most common comorbidity was diabetes. The mean LOS over the study period varied by geographic region and year; in 2014 (the most recent year analyzed), LOS ranged from 7.7 days in Ontario to 13.4 days in the Canadian Prairie for a primary diagnosis and from 18.2 days in Ontario to 25.2 days in Atlantic Canada for a secondary diagnosis. A secondary diagnosis was associated with higher rates of continuing care compared with a primary diagnosis (10.6%-24.2% vs 4.6%-12.1%).

CONCLUSION

This study demonstrated that the mean LOS associated with ABSSSI due to MRSA in Canada was minimally 7 days. Clinical management strategies, including medication management, which might facilitate hospital discharge, have the potential to reduce hospital LOS and related economic burden associated with ABSSSI caused by MRSA.

Profile of tedizolid phosphate and its potential in the treatment of acute bacterial skin and skin structure infections

Tedizolid phosphate is the first once-daily oxazolidinone approved by the United States Food and Drug Administration for the treatment of acute bacterial skin and skin structure infections (ABSSSI). It is more potent in vitro than linezolid against methicillin-resistant Staphylococcus aureus (MRSA) and other gram-positive pathogens causing ABSSSI, even retaining activity against some linezolid-resistant strains. Tedizolid is approximately 90% protein bound, leading to lower free-drug concentrations than linezolid. The impact of the effect of food, renal or hepatic insufficiency, or hemodialysis on tedizolid's pharmacokinetic have been evaluated, and no dosage adjustment is needed in these populations. In animal and clinical studies, tedizolid's effect on bacterial killing is optimized by the free-drug area under the curve to minimum inhibitory concentration ratio (fAUC/MIC). The 200 mg once-daily dose is able to achieve the target fAUC/MIC ratio in 98% of simulated patients. Two Phase III clinical trials have demonstrated the noninferiority of tedizolid 200 mg once daily for 6 days to linezolid 600 mg twice daily for 10 days. In vitro, animal, and clinical studies have failed to demonstrate that tedizolid inhibits monoamine oxidase to a clinically relevant extent. Tedizolid has several key advantages over linezolid including once daily dosing, decreased treatment duration, minimal interaction with serotonergic agents, possibly associated with less adverse events associated with the impairment of mitochondrial protein synthesis (eg, myelosuppression, lactic acidosis, and peripheral/optic neuropathies), and retains in vitro activity against linezolid-resistant gram-positive bacteria. Economic analyses with tedizolid are needed to describe the cost-effectiveness of this agent compared with other options used for ABSSSI, particularly treatment options active against MRSA.

Resource use in patients hospitalized with complicated skin and soft tissue infections in Europe and analysis of vulnerable groups: the REACH study

BACKGROUND

Hospitalized patients with complicated skin and soft tissue infections (cSSTI) present a substantial economic burden, and resource use can vary according to the presence of comorbidities, choice of antibiotic agent, and the requirement for initial treatment modification. REACH (NCT01293435) was a retrospective, observational study aimed at collecting empirical data on current (year 2010-2011) management strategies of cSSTI in 10 European countries.

METHODS

Patients (n = 1995) were aged ≥18 years, hospitalized with a cSSTI and receiving intravenous antibiotics. Data, collected via electronic Case Report Forms, detailed patient characteristics, medical history, disease characteristics, microbiological diagnosis, disease course and outcomes, treatments before and during hospitalization, and health resource consumption.

RESULTS

For the analysis population, mean length of hospital stay (including duration of hospitalizations for patients with recurrences) was 18.5 days (median 12.0). Increased length of hospital stay was found for patients with comorbidities vs those without (mean = 19.9; [median = 14.0] days vs 13.3 [median = 8.0] days), for patients with methicillin-resistant Staphylococcus aureus compared with patients with methicillin-sensitive S. aureus (mean = 27.7 [median = 19.5] days vs 18.4 [median = 13.0] days) and for patients requiring surgery (mean = 24.4 [median = 16.0] days vs 15.0 [median = 11.0] days). Patients requiring modification of their initial antibiotic treatment had an associated increase in mean length of hospital stay of 10.9 days (median = 6.5) and additional associated hospital resource use. A multivariate analysis confirmed the association of nosocomial infections, comorbidities, directed treatment, recurrent infections, diabetes, recent surgery, and older age (≥65 years), with longer hospital stay.

CONCLUSIONS

This study provides real-life data on factors that are expected to impact length of hospital stay, to guide clinical decision-making to improve outcomes, and reduce resource use in patients with cSSTI.

Incidence and cost of hospitalizations associated with Staphylococcus aureus skin and soft tissue infections in the United States from 2001 through 2009

BACKGROUND

The emergence of community-associated methicillin-resistant Staphylococcus aureus (SA) and its role in skin and soft tissue infections (SSTIs) accentuated the role of SA-SSTIs in hospitalizations.

METHODS

We used the Nationwide Inpatient Sample and Census Bureau data to quantify population-based incidence and associated cost for SA-SSTI hospitalizations.

RESULTS

SA-SSTI associated hospitalizations increased 123% from 160,811 to 358,212 between 2001 and 2009, and they represented an increasing share of SA- hospitalizations (39% to 51%). SA-SSTI incidence (per 100,000 people) doubled from 57 in 2001 to 117 in 2009 (p<0.01). A significant increase was observed in all age groups. Adults aged 75+ years and children 0-17 years experienced the lowest (27%) and highest (305%) incidence increase, respectively. However, the oldest age group still had the highest SA-SSTI hospitalization incidence across all study years. Total annual cost of SA-SSTI hospitalizations also increased and peaked in 2008 at $4.84 billion, a 44% increase from 2001. In 2009, the average associated cost of a SA-SSTI hospitalization was $11,622 (SE=$200).

CONCLUSION

There has been an increase in the incidence and associated cost of SA-SSTI hospitalizations in U.S.A. between 2001 and 2009, with the highest incidence increase seen in children 0-17 years. However, the greatest burden was still seen in the population over 75 years. By 2009, SSTI diagnoses were present in about half of all SA-hospitalizations.

The impact of initial antibiotic therapy (linezolid, vancomycin, daptomycin) on hospital length of stay for complicated skin and soft tissue infections

Background

Empiric therapy of inpatient skin and soft tissue infections (SSTIs) generally require methicillin resistant Staphylococcus aureus (MRSA) coverage. Limited data are available to directly compare the effect of initial antibiotic choice on treatment outcomes and length of stay (LOS).

Objective

To assess potential differences in length of hospital stay when inpatients with complex skin and soft tissue infections (SSTIs) were initially treated with either vancomycin, linezolid, or daptomycin.

Methods

A retrospective review of 219 patients diagnosed with inpatient SSTI who received linezolid, vancomycin, or daptomycin for >48 hours was performed. Data collected included demographics, comorbidities, microbiologic/laboratory data, additional management (surgical, non-study antibiotics), hospital LOS, treatment outcome and morbidity/mortality.

Results

The three groups evaluated were linezolid (n = 45), vancomycin (n = 90) daptomycin (n = 84). There was no difference between the three groups with respect to gender, age, comorbidities, leukocytosis, fever, antibiotics prior to admission, site of infection culture results and surgical intervention. One death was recorded, not associated with diagnosis of SSTI. No significant difference in LOS was found (P = 0.525) between the 3 groups. The mean LOS in entire cohort was 4.5 days (SD ± 2.5); thirty patients had prolonged LOS for non-SSTI reasons; reanalyzing the data without these 30 patients did not produce any difference in the mean LOS between the 3 groups. Switching vancomycin just prior to discharge to facilitate outpatient therapy was common but did not impact LOS.

Conclusions

No difference was detected in hospital length of stay with respect to the initial choice of antibiotic (linezolid, vancomycin, or daptomycin) for SSTI. The three antibiotic regimens were equally effective in treating SSTIs as judged by LOS, irrespective of age, gender, comorbidities or baseline severity of SSTI. Given the large standard deviation in LOS, this result should be confirmed by larger studies.

Comparative analysis of empiric antimicrobial treatments for skin and soft tissue infections in newly hospitalized patients

PURPOSE

Intravenous vancomycin is the standard empiric treatment for complicated skin and soft tissue infections (SSTIs) due to its coverage against methicillin-resistant Staphylococcus aureus (MRSA). The objective of this study was to compare the hospital length of stay (LOS) between vancomycin-treated patients and patients receiving newer anti-MRSA agents. The study also aimed to identify factors associated with therapy change in patients receiving vancomycin on admission.

METHODS

Electronic medical records were used to conduct this retrospective cohort study. The LOS was compared among 5 groups of adult patients with admission diagnoses for SSTI who were initiated on linezolid, daptomycin, ceftaroline, tigecycline, or vancomycin. Survival analysis was used to identify factors associated with therapy change from vancomycin to another study medication.

RESULTS

Vancomycin was prescribed in 1046 (92%) admissions. Although none of the between-group differences in LOS reached statistical significance, there was a trend toward shorter LOS in vancomycin-treated patients compared to linezolid-treated patients (P = .059). Coagulopathy was independently associated with increased likelihood of therapy change from vancomycin (hazard ratio = 4.71; P <.001).

CONCLUSIONS

In the treatment of SSTI, newer agents result in LOS comparable to vancomycin. In patients initiated on vancomycin, therapy change was associated with longer LOS. Coagulopathy was independently associated with increased probability of therapy change.

Economic burden of inpatient and outpatient antibiotic treatment for methicillin-resistant Staphylococcus aureus complicated skin and soft-tissue infections: a comparison of linezolid, vancomycin, and daptomycin

Background

Previous economic analyses evaluating treatment of methicillin-resistant Staphylococcus aureus (MRSA) complicated skin and soft-tissue infections (cSSTI) failed to include all direct treatment costs such as outpatient parenteral antibiotic therapy (OPAT). Our objective was to develop an economic model from a US payer perspective that includes all direct inpatient and outpatient costs incurred by patients with MRSA cSSTI receiving linezolid, vancomycin, or daptomycin.

Methods

A 4-week decision model was developed for this economic analysis. Published literature and database analyses with validation by experts provided clinical, resource use, and cost inputs on data such as efficacy rate, length of stay, adverse events, and OPAT services. Base-case analysis assumed equal efficacy and equal length of stay for treatments. We conducted several sensitivity analyses where assumptions on resource use or efficacy were varied. Costs were reported in year-end 2011 US dollars.

Results

Total treatment costs in the base-case were lower for linezolid ($10,571) than vancomycin ($11,096), and daptomycin ($13,612). Inpatient treatment costs were $740 more, but outpatient costs, $1,266 less with linezolid than vancomycin therapy due to a switch to oral linezolid when the patient was discharged. Compared with daptomycin, both inpatient and outpatient treatment costs were lower with linezolid by $87 and $2,954 respectively. In sensitivity analyses, linezolid had lower costs compared with vancomycin and daptomycin when using differential length of stay data from a clinical trial, and using success rates from a meta-analysis. In a scenario without peripherally inserted central catheter line costs, linezolid became slightly more expensive than vancomycin (by $285), but remained less costly than daptomycin (by $2,316).

Conclusion

Outpatient costs of managing MRSA cSSTI may be reduced by 30%–50% with oral linezolid compared with vancomycin or daptomycin. Results from this analysis support potential economic benefit and cost savings of using linezolid versus traditional OPAT when total inpatient and outpatient medical costs are evaluated.

Treatment failure and costs in patients with methicillin-resistant Staphylococcus aureus (MRSA) skin and soft tissue infections: a South Texas Ambulatory Research Network (STARNet) study

OBJECTIVE

To measure the incidence of treatment failure and associated costs in patients with methicillin-resistant Staphylococcus aureus skin and soft tissue infections (SSTIs).

METHODS

This was a prospective, observational study in 13 primary care clinics. Primary care providers collected clinical data, wound swabs, and 90-day follow-up information. Patients were considered to have "moderate or complicated" SSTIs if they had a lesion ≥5 cm in diameter or diabetes mellitus. Treatment failure was evaluated within 90 days of the initial visit. Cost estimates were obtained from federal sources.

RESULTS

Overall, treatment failure occurred in 21% of patients (21 of 98) at a mean additional cost of $1,933.71 per patient. In a subgroup analysis of patients who received incision and drainage, those with moderate or complicated SSTIs had higher rates of treatment failure than those with mild or uncomplicated SSTIs (36% vs. 10%; P=.04).

CONCLUSIONS

One in 5 patients presenting to a primary care clinic for a methicillin-resistant S. aureus SSTI will likely require additional interventions at an associated cost of almost $2,000 per patient. Baseline risk stratification and new treatment approaches are needed to reduce treatment failures and costs in the primary care setting.

Optimizing delivery of care for patients with MRSA infection: focus on transitions of care

Staphylococcus aureus is among the most prevalent pathogens isolated from hospitalized patients; those infected with methicillin-resistant strains have longer hospital stays and higher total costs compared with those infected by methicillin-susceptible strains. A multidisciplinary team of health care providers, including hospitalists and other hospital-based physicians, clinical pharmacists, infectious disease specialists, infection control professionals, and case managers, is key to improving treatment and outcomes in these patients. Optimizing transitions of care for hospitalized patients with S aureus infections can improve quality and reduce total costs of care. Hospital length of stay can be shortened by initiating timely, appropriate empiric therapy and by transitioning suitable patients to outpatient antimicrobial therapy. The number of hospitalizations can be reduced by identifying patients who are suitable candidates for initial outpatient antimicrobial therapy. Consistent with good antimicrobial stewardship, the risk of resistance can be minimized by de-escalating empiric therapy to a more narrow-spectrum agent once culture and susceptibility testing results are known. There are several antimicrobial agents available for the management of S aureus infections, including methicillin-resistant S aureus. Consideration of these agents' characteristics may facilitate optimal transition of patients through health care settings.