Perianal Strep Infection

Naturally, we are all accustomed to evaluating children for rashes. Most often I am simply attempting to define the lack of characteristics that are concerning for more significant medical conditions (petechiae, purpura, vesicles, bull, target lesions, urticaria, desquamation). Then I consider whether this is a presentation of typical childhood illness (Fifth’s Disease, molluscum contagiosum, pityriasis rosea, etc). Here is a condition that is often forgotten about that you can add to your list of typical childhood rashes… one that many times gets overlooked and called “diaper rash:” Perianal Strep.

• Usually occurs in children <10 years of age – particularly infants and pre-school aged kids.
• Group A Streptococcus pyogenes (Yes the same that causes “Strep Throat”) can cause local skin infection in the perianal region (just as it can in skin folds – see Intertrigo).
• Presentation includes:
  • Well-demarcated red area surrounding the anus (usually “Beefy-red” and usually extending 2cm around the anus) – sometimes with exudates
  • Tenderness
  • Painful defecations (leading to constipation due to toileting aversion)
  • Itching
  • Fissures
  • Bloody streaks in stool
  • Vulvovaginits

• Often misdiagnosed as:
  • Pin-worm infection
  • Candidiasis
  • Diaper Dermatitis
  • Simple anal fissures
  • Sexual abuse

• You can diagnosis it as you would Strep Throat – with a Rapid Strep test and a Culture

• Treatment:
  • Oral Penicillin VK or Clarithromycin or Augmentin for 7-10 days.
  • The efficacy of topical therapies is questionable.

Lehman R, Pinder S. Streptococcal perianal infection in children. BMJ 2009; 338:b1517

Echeverria FM, Lopez-Menchero OJ, Maranon PR, Miguez NC, Sanchez SC, Vasquez LP. Isolation of group A hemolytic streptococcus in children with perianal dermatitis. An Pediatr (Barc) 2006;64:153-7.