Pityriasis rubra pilaris - External and Internal Eye
Pityriasis rubra pilaris (PRP) is a papulosquamous disorder with characteristic clinical features. There are both acquired and heritable forms. It is characterized in the acquired form by fairly rapid onset of extensive, confluent, scaling plaques in association with thick keratoderma of the hands. It often begins in the scalp and rapidly involves the trunk and extremities.
The heritable form of the disease begins in early childhood, while the incidence of the acquired form peaks in both childhood and mid-to-late adulthood. In addition to the generalized disease, a limited form is seen in both children and adults. HIV-associated PRP can be associated with nodulocystic acne and responds to antiretroviral therapy.
Peripheral ulcerative keratitis and cicatricial ectropion have been seen with PRP. Blurred vision and dry eyes may be reported.
L44.0 – Pityriasis rubra pilaris
3755001 – Pityriasis rubra pilaris
- Psoriasis – See Diagnostic Pearls.
- Seborrheic dermatitis – Much more responsive to standard therapies. PRP is often resistant to conventional therapies for seborrheic dermatitis. In addition, the progression of body surface involvement will distinguish PRP from seborrheic dermatitis.
- Mycosis fungoides / Sezary syndrome – Generalized lymphadenopathy, circulating malignant lymphocytes as determined by flow cytometry, leonine facies, a CD4/CD8 ratio greater than 10 as determined by flow cytometry.
- Erythrokeratoderma variabilis – More than 90% of patients present within the first year of life.
- Drug eruption – Often present with urticarial, exanthematous, or vesicular/bullous lesions. In addition, systemic symptoms are more pronounced, including fever, lymphadenopathy, and facial edema. Eosinophilia on CBC and histology are often seen (but not an invariable finding). Medication history will help.
- Atopic dermatitis – Patients are often aware of their atopic history, and the condition commonly starts in childhood. Look for lichenified plaques on the flexural surfaces and neck.
- Erythrokeratodermia variabilis