Wise Use of Antibiotics

Skin and Soft Tissue Infection Management, Longer Does Not Always Equal Better

Author: Megan Hamner, MD| Pediatric Infectious Diseases Fellow

Column Editor: Rana El Feghaly, MD, MSCI | Director, Clinical Services | Director, Outpatient Antibiotic Stewardship Program | Associate Professor of Pediatrics, UMKC School of Medicine

Skin and soft tissue infections (SSTIs) are common conditions seen in the pediatrician’s everyday practice and, after respiratory tract infections, are the second most common diagnoses leading to pediatric antibiotic prescriptions.¹ The recommended treatment strategies for SSTIs have evolved over the years as new literature has been published supporting shorter treatment durations. Despite these new recommendations, evaluation of provider prescribing practices across the United States has revealed that 77-93% of patients receive greater than 7 days of antibiotics for SSTIs which is defined as a long course of therapy.^2,3 Reducing unnecessary or prolonged antibiotic exposure is an important facet of antimicrobial stewardship. Adhering to national treatment guidelines can help pediatricians provide optimal care for their patients while being good antibiotic stewards.

Impetigo requires 5-7 days of topical or systemic antibiotics

Impetigo is a very common superficial SSTI usually caused by Staphylococcus aureus or Streptococcus pyogenes. Per the Infectious Diseases Society of American (IDSA) Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections, impetigo can be treated topically or systemically.⁴ Topical treatment for 5 days with mupirocin is recommended for patients with ≤5 small lesions in easy-to-reach locations. Systemic treatment with 7 days of cephalexin is recommended for patients with ≥5 lesions, extensive lesions, or lesions near the mouth.⁴ Antibiotic coverage of methicillin-resistant Staphylococcus aureus (MRSA) is not needed unless community rates are high.

Erysipelas and cellulitis can be treated with 5 days of systemic antibiotics

Erysipelas and cellulitis are similar appearing infections involving the dermis. Erysipelas classically presents with well-demarcated areas of erythema, warmth and tenderness compared to cellulitis which has less defined borders. Erysipelas is usually caused by streptococcal species, particularly S. pyogenes. Cellulitis is typically caused by either S. aureus or S. pyogenes. IDSA Practice Guidelines recommend treatment with cephalexin for 5 days for both conditions.⁴ Treatment can be extended to up to 10 days if the infection has not improved by the fifth day of therapy. MRSA is a rare cause of cellulitis and should not be empirically covered unless there are specific risk factors present, such as personal or family history of MRSA.

Cutaneous abscesses require 5 days of systemic antibiotics after incision and drainage

Cutaneous abscesses are localized walled-off collections of purulent material in the dermis and subcutaneous tissues. Abscesses are commonly caused by S. aureus and S. pyogenes. MRSA prevalence varies by community but can be high, so empiric coverage is reasonable for this diagnosis. IDSA Practice Guidelines recommend incision and drainage as the primary treatment needed for abscesses.⁴ Although adult literature suggests that drainage of the abscess without antibiotics may be enough, recent pediatric literature suggests improved cure rates with the addition of either clindamycin or trimethoprim/sulfamethoxazole for 5-7 days.⁵

Folliculitis and paronychia do not typically require systemic antibiotics

Folliculitis is a superficial infection of the hair follicle predominately caused by S. aureus. These infections most often resolve without antimicrobial therapy. Hot tub folliculitis occurs after exposure to underchlorinated pools or hot tubs/whirlpools. These infections are caused by Pseudomonas aeruginosa and typically resolve within 7-10 days without antimicrobial therapy. Paronychia is an infection of the soft tissue folds surrounding the finger or toenail. It typically requires drainage. These infections can be polymicrobial with mixed aerobic and anaerobic organisms including S. aureus, S. pyogenes, Eikenella corrodens and Bacteroides species. Mild- to-moderate cases can be treated with warm compresses and/or incision and drainage. Severe infections with concern for deeper infection can be treated with either cephalexin or amoxicillin/clavulanate for 5 days.⁶

Why do providers treat SSTIs with longer antibiotic courses?

Providers often treat SSTIs with prolonged antibiotic courses due to concerns for treatment failure or post-streptococcal infection complications such as acute rheumatic fever or glomerulonephritis. Acute rheumatic fever occurs very rarely in the U.S. (~1:100,000) and is not associated with skin infections due to S. pyogenes. Antibiotic treatment of S. pyogenes does not prevent the development of glomerulonephritis and instead works to prevent the spread of nephritogenic strains in the community.

In conclusion, shorter antibiotic courses for SSTIs are effective and are recommended by the current national guidelines. Adhering to the recommendations summarized here allows us to be the best stewards possible for our patients.

References:

1. Yonts AB, Kronman MP, Hamdy RF. The burden and impact of antibiotic prescribing in ambulatory pediatrics. Curr Probl Pediatr Adolesc Health Care. 2018 Nov;48(11):272-288.
2. King LM, Hersh AL, Hicks LA, Fleming-Dutra KE. Duration of outpatient antibiotic therapy for common outpatient infections, 2017. Clin Infect Dis. 2020 Sep 16:ciaa1404.
3. Jaggi P, Wang L, Gleeson S, Moore-Clingenpeel M, Watson JR. Outpatient antimicrobial stewardship targets for treatment of skin and soft-tissue infections. Infect Control Hosp Epidemiol. 2018 Aug;39(8):936-940.
4. Stevens DL, Bisno AL, Chambers HF, Dellinger EP, Goldstein EJ, Gorbach SL, Hirschmann JV, Kaplan SL, Montoya JG, Wade JC; Infectious Diseases Society of America. Practice guidelines for the diagnosis and management of skin and soft tissue infections: 2014 update by the Infectious Diseases Society of America. Clin Infect Dis. 2014 Jul 15;59(2):e10-52.
5. Talan DA, Mower WR, Krishnadasan A, Abrahamian FM, Lovecchio F, Karras DJ, Steele MT, Rothman RE, Hoagland R, Moran GJ. Trimethoprim-sulfamethoxazole versus placebo for uncomplicated skin abscess. N Engl J Med. 2016 Mar 3;374(9):823-32.
6. Pierrart J, Delgrande D, Mamane W, Tordjman D, Masmejean EH. Acute felon and paronychia: Antibiotics not necessary after surgical treatment. Prospective study of 46 patients. Hand Surg Rehabil. 2016 Feb;35(1):40-3.