Зображення 00435. Pityriasis rosea

"The herald patch" of a common dermatosis, pityriasis rosea. The 3–5 cm size oval patch appears a couple of weeks before a wider eruption of smaller ovals affecting the skin of the trunk and proximal extremities. This spontaneously limiting disease is probably caused by herpesvirus 7. No treatment is needed: no therapy shortens the 3–8 weeks of skin symptoms.