Pityriasis rosea (PR) is a self-limiting papulosquamous dermatosis that is found in all Fitzpatrick skin types (I to VI), with some distinct presentations in patients with skin of color.
PR is associated with drugs (barbiturates, metronidazole, terbinafine, isotretinoin, gold, and clozapine), vaccinations (hemagglutinin 1 neuraminidase 1 [H1N1]), and viruses (human herpes virus [HHV]-6, HHV-7, and HHV-8).
The etiology of PR is unclear. However, antiviral therapies are proving to be effective in decreasing the duration and severity of this condition.
Pityriasis rosea (PR) is an acute, self-limiting papulosquamous dermatosis that is thought to have a viral origin. It occurs over a broad age range, most often between the ages of 10 and 35 years, and rarely before the age of 2. The peak occurrence is during the spring and fall seasons. It usually has a classic clinical presentation, is asymptomatic, and undergoes spontaneous resolution in 6 to 10 weeks.
PR is found worldwide without a racial predilection. In an overview of disorders more commonly seen in patients with skin of color, PR was listed as occurring in about 2% of patients1 [Table 25-1].
TABLE 25-1General information on pityriasis rosea |Favorite Table|Download (.pdf) TABLE 25-1 General information on pityriasis rosea
• Pityriasis rosea occurs in 2% of dermatology patients with skin of color.
• Onset is usually between the ages of 10 and 35 years.
• Spontaneous resolution occurs in 6 to 10 weeks.
The incidence of PR has been decreasing. This may be due to its self-limiting nature, which could result in cases of PR never coming to the attention of a physician. Furthermore, dermatologists are usually the second or third physician a patient sees for the diagnosis and treatment of PR. By this point, the condition has often cleared up and the patient is seeking to determine the cause of the dermatosis, and/or the patient has healed but has been left with postinflammatory dyspigmentation (often in the form of hyperpigmentation).
Because PR may differ clinically in those with skin of color, in comparison with patients who have Fitzpatrick skin types I to III, it is important to highlight the clinical differences. It is also necessary to note the effects of certain treatment options for patients with skin of color.
PR is thought to be due to a virus or bacterium. Most of the literature points to a viral etiology.2 Human herpes virus (HHV)-6 and HHV-7 are the two viruses most closely associated with PR, although this correlation is inconclusive.
HHV-6 belongs to the Roseolovirus genus and is closely homologous with HHV-7; thus HHV-7 belongs to the same genus. HHV-6 is widespread in the population and persists, often in a latent state, in its hosts’ monocytes and bone marrow progenitor cells and ...