Itchy perianal erythema
This young patient had a perianal rash that did not respond to topical clotrimazole. What is your diagnosis?
Penicillin provides prompt improvement
Penicillin V or amoxicillin (40 mg/kg/ day divided into 3 oral doses daily) for 10 days is effective as a first-line treatment for perianal streptococcal dermatitis (strength of recommendation [SOR]: C).4
The amoxicillin suspension tastes better than the penicillin suspension, which may lead to better compliance in children.5
Topical mupirocin (Bactroban) 2% applied 3 times daily may also be effective. If a patient is allergic to penicillin, you may want to consider the macrolides (erythromycin, azithromycin, clarithromycin) or clindamycin.1
Once the patient takes his or her medication, clinical improvement is prompt; it often occurs within 24 hours.
Relapse is common. Clinical follow-up is indicated as relapse occurs in up to 39% of cases.6 Relapses usually respond to repeat courses with the same antibiotic. A prolonged treatment course (14 to 21 days) may increase cure rates in patients with relapse.1
No relapse for our young patient
Our young patient received a 10-day course of amoxicillin and his case of perianal streptococcal dermatitis resolved. He did not have a relapse.
Acknowledgments
The authors thank Robert Norman, MD for identifying and sharing this case.
Correspondence
Andrew D. Schechtman, MD, San Jose-O’Connor Hospital Family Medicine Residency, 455 O’Connor Dr.#210, San Jose, CA 95128; aschecht@stanford.edu
