Lichen Planus
Another condition that may be misdiagnosed as psoriasis is lichen planus. This skin condition is considered to be autoimmune. It leads to irritation and swelling in the mucous membranes, nails, hair, as well as skin. On the limbs and wrists, lesions caused by lichen planus may be quite similar to those in psoriasis. But on other areas of the body, they tend to lack characteristic scales and be purple instead of thick like in psoriasis. In addition, lichen planus may appear in mucosal tissues, while psoriasis does not. Under the microscope, both lichen planus and psoriasis may have an acanthotic look. However, lichen planus may cause a band-like damaged area between the middle and upper layer of skin. [5]
