Parapsoriasis - What Is It?

A continuum is thought to exist: 

Chronic dermatitis ---> Parapsoriasis ---> T cell lymphoma (mycosis fungoides)

Parapsoriasis may be defined thus

1. Plaque-type (usually elderly and on legs; circinate patches may be red, yellow, brown, pink; plaques tend to be thin)

    (sometimes called chronic scaly superficial dermatitis)

.. Small plaque

.. Large plaque

2. Lichenoid

.. Pityriasis lichenoides

.... acute

.... chronic

Most cases aren't painful or itchy

If this is part of DDx -> consider punch biopsies to exclude a T cell lymphoma

Else histology changes tend to be non-specific

Emollients very important to hydrate skin

Otherwise,Rx tends to be that for dermatitis, including topical c.steroids and UV therapy

Always a good reference site, I find ...

Parapsoriasis - Medscape Reference

emedicine.medscape.com/article/1107425-overviewApr 19, 2013 - Parapsoriasis describes a group of cutaneous diseases that can be characterized by scaly patches or slightly elevated papules


DDx includes
- dermatitis (particularly circinate/nummular type)
- psoriasis (plaque or guttate form)
- T cell lymphoma (mycosis fungoides)
- Pityriasis rosea
- Syphylis (secondary)

--> biopsies

--> ?syphylis serology