The Case

A 49-year-old female with a history of diet-controlled diabetes presents to the emergency department with erythema and warmth to her lower left leg measuring 8 cm by 12 cm for the past three days. The patient is neurovascularly intact, and there is no evidence of deep vein thrombosis (DVT) on ultrasound. She is not febrile, and her white blood cell count is 11,700.

Clinical Question

Does the use of a long-acting IV antibiotic as part of a clinical pathway in the emergency department for patients with skin and soft tissue infections reduce hospitalizations?

Background

Patients commonly present to the emergency department with skin and soft tissue infections (SSTIs), and the incidence is increasing.^1,2 These types of SSTI include cellulitis and abscesses.

Most patients with SSTIs can be managed as outpatients. However, the average length of stay for inpatient care is one week, and associated care costs are close to $5 billion a year in the United States.³ The mortality rate for hospitalized patients with SSTI is <0.05 percent.^4,5

The only reason for in-patient management in 40 percent of patients was to provide parenteral antibiotics.⁶ This has led to greater interest in long-acting parenteral antibiotics as a possible alternative to admission.

Reference: Talan DA, Mower WR, Lovecchio FA, et al. Pathway with single-dose long-acting intravenous antibiotic reduces emergency department hospitalizations of patients with skin infections. Acad Emerg Med. 2021;28(10):1108-1117.

• Population: Adults ≥18 years old with abscess, cellulitis, or wound infection believed or confirmed to be due to gram-positive bacteria and an area of infection of at least 75 cm²
  • Excluded: Multiple exclusions, refer to research paper.
• Intervention: Single dose of IV dalbavancin (1,500 mg if creatinine clearance ≥30 mL/min or 1,125 mg for creatinine clearance <30 mL/min not on dialysis) as part of a clinical pathway; intervention also included a follow-up telephone call 24 hours after the visit and a follow-up appointment 48–72 hours after discharge
• Comparison: Usual care before new clinical pathway
• Outcome:
  • Primary Outcome: Rate of hospitalization
  • Secondary Outcomes: Hospitalizations through 44 days, health resource utilization (length of stay, level of care, major surgical interventions, ICU admissions), adverse events, and patient-related outcomes (satisfaction, work productivity, and quality-of-life surveys at 14 days)

Authors’ Conclusions

“Implementation of an ED SSTI clinical pathway for patient selection and follow-up that included use of a single-dose, long-acting IV antibiotic was associated with a significant reduction in hospitalization rate for stable patients with moderately severe infections.”

Results

More than 3,000 patients were screened during the before-and-after study for inclusion, with only 5 percent deemed eligible. The median age of participants was in the late 40s, two-thirds were male, and more than 80 percent had cellulitis.

Key Result: The rate of hospitalization was lower after the implementation of the new clinical pathway that included a single-dose long-acting IV antibiotic.

• Primary Outcome: Rate of hospitalization rate at the time of initial care
  • 38.5 percent usual care versus 17.6 percent new pathway, absolute difference 20.8 percent (95% CI; 10.4–31.2%)
• Secondary Outcome: Mild, moderate, and severe adverse events were all more common in the new pathway group. No deaths were reported in the study. Details of the patient-related outcomes are available in the supplemental material (see Table 1).

Table 1: Secondary Outcomes

Evidence-Based Medicine Commentary

1. Before/After Study Design: One drawback to this type of study design is the possible contamination of treatment effect by confounders such as other system or local factors. For example, it’s not clear how much the protocol to ensure close outpatient follow-up or education contributed to the lower hospitalization rates.
2. Hawthorne Effect: It is possible that some portion of the treatment effect was the result of the clinicians being aware that their management of SSTI was being evaluated and that discharge was encouraged. This could have introduced a Hawthorne effect, which is when people change their normal behavior in response to knowing they are being observed.
3. Magnitude of Impact: There was a large absolute decrease in hospitalizations after the pathway was introduced (21 percent). However, only 5 percent of patients screened for eligibility were enrolled. That means the data do not directly apply to most patients who present with SSTI, which limits impact of this intervention.
4. Cost and Creep: This medication costs approximately $5,000 for 1,500 mg. It is unclear if this would be a cost-effective strategy compared to admitting patients. It would depend on in which country the pathway was implemented. There could also be a concern with indication creep, which could lead to overuse and potentially increased antibiotic resistance.
5. Conflict of Interest: This was an industry-funded study with multiple authors declaring conflicts of interest. While this does not make the data or interpretation wrong, it should make us more skeptical.

Bottom Line

A clinical pathway that provides a long-acting IV and the ability to establish expedited telephone and in-person follow-up is associated with a decrease in hospitalizations for patients with moderately severe cellulitis.

Case Resolution

You engage in shared decision making with the woman and offer her admission to the hospital for IV antibiotic inpatient management or a single-dose long-acting IV antibiotic and outpatient management. She chooses not to be admitted and is discharged home with follow-up instructions.

Remember to be skeptical of anything you learn, even if you heard it on the Skeptics’ Guide to Emergency Medicine.

Thank you to Dr. Lauren Westafer, an assistant professor in the department of emergency medicine at the University of Massachusetts Medical School–Baystate, for her help with this review. 

References:

1. Pallin DJ, Egan DJ, Pelletier AJ, et al. Increased US emergency department visits for skin and soft tissue infections, and changes in antibiotic choices, during the emergence of community-associated methicillin-resistant Staphylococcus aureus. Ann Emerg Med. 2008;51(3):291-298.
2. Edelsberg J, Taneja C, Zervos M, et al. Trends in US hospital admissions for skin and soft tissue infections. Emerg Infect Dis. 2009;15(9):1516-1518.
3. Suaya JA, Mera RM, Cassidy A, et al. Incidence and cost of hospitalizations associated with Staphylococcus aureus skin and soft tissue infections in the United States from 2001 through 2009. BMC Infect Dis. 2014;14:296.
4. Sabbatini AK, Nallamothu BK, Kocher KE. Reducing variation in hospital admissions from the emergency department for low-mortality conditions may produce savings. Health Aff (Millwood). 2014;33(9):1655-1663.
5. LaPensee KT, Fan W, Economic burden of hospitalization with antibiotic treatment for bacteremia, sepsis in the US. Paper presented at: ID Week Annual Meeting; October 17–21, 2012; San Diego, CA.
6. Talan DA, Salhi BA, Moran GJ, et al. Factors associated with decision to hospitalize emergency department patients with skin and soft tissue infection. West J Emerg Med. 2015;16(1):89-97.