This papulosquamous eruption is most common in young adults. A single oval patch is generally noted several days before a more generalized, fawn-colored rash erupts. This rash is most prevalent on the trunk, and the proximal upper and lower extremities. The rash spontaneously disappears over 5 to 6 weeks. The diagnosis is:
- pityriasis rosea
- tinea corporis
- atopic dermatitis
This is the classic presentation of pityriasis rosea. Remember that the differential diagnosis includes secondary syphilis, so if there is a positive sexual history - consider ordering a VDRL/RPR. The "herald" patch which is described is pathognomonic for pityriasis.
Know Your Content Blueprint
Pityriasis rosea is covered as part of the NCCPA™ Dermatology Content Blueprint (5%)