Do Pediatric Abscesses Require Antibiotics in Addition To I&D?

Sarah Klemencic

Disclosures

AccessMedicine from McGraw-Hill 

Background

Community acquired methicillin resistant Staphylococcus aureus (MRSA) is on the rise nationwide and emergency departments (EDs) across the country are seeing evidence of this in the increasing rate of patients with skin infections. In 2005, Emergency Physicians (EPs) diagnosed 3.4 million cases of skin infections in the U.S. compared to 1.2 million in 1993.[1,2] Incision and drainage (I&D) form the cornerstone of treatment for abscesses, but the role of antibiotics in addition to I&D, particularly for MRSA, has been unclear. This issue is especially pertinent to the pediatric population where antibiotic exposure and antibiotic resistance are potentially more concerning. In the past, surgical drainage alone has thought to be sufficient treatment. However, with the rise in abscesses due to MRSA, evidence on the necessity of adjunctive antibiotics for pediatric patients with abscesses has been lacking. Several studies in adult patients have found that while antibiotics do not reduce treatment failure when compared to placebo, they may decrease subsequent abscess formation.[3,4] In their study, Duong and Markell sought to clarify the role of role of antibiotics in pediatric patients with skin infections.[2]

Methods

The authors performed a double-blind, randomized, controlled trial to assess the efficacy of antibiotics as an adjunct to incision and drainage in pediatric skin infections. The patients were randomized to 10 days of placebo or trimethoprim/sulfamethoxazole (TMP-SMX) after I&D was performed by the emergency physician. Nontoxic patients between ages 3 months to 18 years were enrolled in a single Level I pediatric trauma emergency department over 19 months. An abscess was defined as acute onset within 1 week, fluctuance, erythema, induration and tenderness with or without purulent drainage. Exclusion criteria included: diabetes, use of oral steroids or other immunosuppressants, recent or current antibiotic usage or any contraindication to the use of TMP-SMX. The diagnosis of skin abscess was made clinically or with bedside ultrasound performed by the treating physician. Incision and drainage was performed by the treating physician with local anesthesia or procedural sedation, based on their discretion. Cultures were sent and isolates were tested for antibiotic susceptibility or resistance using the Microscan systems. Treatment failure at 10 days was the primary outcome. New skin lesions at 10 and 90 day follow up was considered the secondary outcome measure. The study assessed for non-inferiority of placebo in place of TMP-SMX for both outcomes.

Patients and their parents performed all wound cleansing and were instructed to remove any packing within 24 hours. A 10-day follow up visit was scheduled and telephone calls were made to the patient/family on days 2-3, 10-14 and 90. Compliance was assessed by quantifying the medication remaining/used at the 10-day follow up and was considered successful if greater than 50% of the medicine was taken. Treatment failure was described as new lesions within 5 cm of initial lesion, or the presence of erythema, fluctuance, warmth, induration, tenderness or drainage at the initial site. The sample size of 161 patients was calculated using nQuery to assess for non-inferiority using a 95% one-sided confidence interval (CI). A threshold of 7% failure rate was assumed and if the CI had an upper limit less than 7% then non-inferiority was inferred. Limitations included selection bias, as physicians did not enroll all eligible patients.

Results

One hundred sixty-one patients were enrolled and 12 patients were lost to follow up. Fifty-two percent of patients received placebo and 48% received TMP-SMX. Overall compliance was 66% with approximately 10% adverse reaction rate including diarrhea, vomiting, and bad taste. Eighty percent of the isolates were MRSA. All isolates were susceptible to TMP-SMX. Non-inferiority of placebo relative to TMP-SMX was demonstrated in this study for clinical resolution with a failure rate of 5.2% in placebo and 4.1% in the TMP-SMX group. The upper limit of the CI was 6.8% and thus did not exceed the threshold of 7% set by this study. This study demonstrates that surgical drainage alone is appropriate for pediatric skin infections.

Relevance to Emergency Medicine

From 1993 to 2005 there has been an increase of 2.3 million annual ED visits for skin infections.[1,2] The majority of these infections have been shown to be MRSA.[1,3] More antibiotics have been prescribed due to this increased rate of skin infection. The development of multi-drug resistant MRSA should make us all think twice about prescribing antibiotics for abscesses in addition to performing an I&D. While several studies have shown that in adults, I&D alone is sufficient for simple abscesses, this evidence has been lacking in the pediatric population.[3] The results of this study are clear – for simple abscesses in healthy pediatric patients, I&D alone is enough. The study did not address immunocompromised patients, or those with evidence of system illnesses, where antibiotics may be indicated. Limiting antibiotic use may help prevent, or at least delay, the development of antibiotic resistance, and at the same time, provide a cost-savings to families and reducing the incidence of antibiotic side effects.

Comments

3090D553-9492-4563-8681-AD288FA52ACE
Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as:

processing....