Stewardship in the pediatrician’s office: Antibiotic use for skin infections

Skin and soft tissue infections are characterized by invasion of a bacterial pathogen. The type of skin infection correlates with the depth of skin involvement.

A superficial infection such as impetigo is limited to the epidermis,. Extension of the infection to the dermis results in cellulitis. Development of pus in the dermis and subcutaneous tissue produces an abscess.

 

The prevalence of skin and soft tissue infections (SSTIs) in the United States has increased over the past few decades, particularly due to the emergence of MRSA. Ray and colleagues reported that children aged younger than 5 years and adults aged 65 years or older had the highest rates of SSTIs compared with all other age groups. The exact epidemiology of skin infections remains unknown since most of them are not cultured. In this column, we delineate the choice of empiric antibiotics and their duration based on the type of skin infection.

1. Confronting the conundrum of appropriate antibiotic prescription:

Skin infections are a common clinical syndrome encountered by the pediatrician. The spectrum ranges from superficial infection such as impetigo to deeper infection such as cellulitis and abscess. Factors that influence treatment decisions include the type of infection and the presence of systemic signs of infection such as fevers, location, age and the immune status of the child. In addition, knowledge of the local antibiogram can assist in the selection of an appropriate empiric antibiotic.

 

Ulka Kothari

 

Asif Noor

Type of skin infection and management decisions:

• Impetigo accounts for 10% of all pediatric office visits. When feasible, exudate from impetigo or ecthyma should be tested through Gram staining and culture. However, it is reasonable without this testing to treat impetigo with topical antibiotics when it is localized. Consider oral antibiotics only if the patient has extensive disease.

• Cellulitis and erysipelas require oral antibiotics for adequate treatment in the office setting for mild to moderate infection.

• An abscess collection necessitates incision and drainage. Drainage is more effective than antibiotic therapy in an abscess with a size less than 5 cm. A Gram stain and culture should always be sent for bacterial identification and susceptibility. If there is concern for abscess without a definitive collection, an ultrasound can be obtained. If the child has a mild infection without systemic signs or symptoms of infection such as fever, incision and drainage should suffice. A simple dry dressing is recommended as the most effective treatment for a wound. If, however, it is a severe infection with systemic signs or symptoms, or if the child is immunocompromised, empiric antibiotic therapy is indicated against Staphylococcus aureus.

Choice of antibiotics:

Cellulitis and erysipelas are typically caused by group A streptococcus and abscess collections by S. aureus. This distinction is important for appropriate empiric antibiotic selection. The choice should also consider the local antibiogram. An antibiotic against MRSA should be considered if community incidence is more than 15%. Once the identification and susceptibility test results return, antibiotics should be tailored accordingly.

Empiric antibiotic choice and duration (see Figure)

• Impetigo should be treated with either topical mupirocin or retapamulin for 5 days.

• Ecthyma should be treated with an oral antibiotic (cephalexin, clindamycin) for 5 to 7 days.

• Cellulitis in a child who is hemodynamically stable should be treated with either clindamycin alone or with a combination of either sulfamethoxazole-trimethoprim or doxycycline and a beta-lactam (cephalexin or amoxicillin) — providing coverage of group A strep, MRSA and methicillin-susceptible S. aureus. Treatment should be based on the local antibiogram. The recommended duration is 5 to 7 days. Longer durations are indicated only if there is extensive disease, or failure to respond.

Common risk factors for MRSA include history of frequent antibiotic use, cellulitis after penetrating trauma, crowded living conditions and a community MRSA prevalence exceeding 15%. Pediatricians should consider special cases of cellulitis such as after a cat or dog bite (Pasteurella); neutropenia (Pseudomonas); exposure to freshwater (Aeromonas) or saltwater (Vibrio species); penetrating trauma (S. aureus); and varicella (group A strep).

2. Practice guidelines for outpatient settings:

The Infectious Diseases Society of America (IDSA) has published guidelines on the management of SSTIs, which can be found here.

3. Operationalizing an ASP in your office through quality improvement and EHRs:

There is a need for antibiotic stewardship in patients with skin infections. In the ambulatory setting, the goal of treatment is to carefully distinguish between patients with cellulitis vs. abscess and provide appropriate guidelines-based treatment. Clinician education on skin infection management and creating an agreed-upon protocol based on IDSA guidelines, the local antibiogram and the availability of resources for incision and drainage are factors to consider. Pediatricians can then create an order set with defaulted appropriate choice and duration of antibiotics. Educating clinicians on the local antibiogram and making it available to aid their choice of antibiotic would also contribute to antimicrobial stewardship program efforts.

For more information:

Ulka Kothari, MD, is a general pediatrician, physician informaticist and director of pediatric ambulatory quality at NYU Winthrop Hospital. She can be reached at ulka.kothari@nyulangone.org.

Asif Noor, MD, FAAP, is an assistant professor of pediatrics at NYU Long Island School of Medicine. He can be reached at asif.noor@nyulangone.org.

References:

Cole C, Gazewood J. Am Fam Physician. 2007;75:859-864.

Dukic VM, et al. PLoS One. 2013;doi:10.1371/journal.pone.0052722.

Duong M, et al. Ann Emerg Med. 2010;doi:10.1016/j.annemergmed.2009.03.014.

Nelson CE, et al. Clin Pediatr (Phila). 2018;doi:10.1177/0009922817738329.

Ray GT, et al. BMC Infect Dis. 2013;doi:10.1186/1471-2334-13-252.

Stevens DL, et al. Clin Infect Dis. 2014;doi:10.1093/cid/ciu296.