Eczema and psoriasis share many similarities. They are both chronic skin rashes and present with itchy red rashes. However, have differences in their presentation and have different underlying pathology.
Atopic eczema is a form of eczema that often occurs from infancy and childhood. It presents with itchy red rashes that affects mainly the flexural areas, like the elbow and knee bends and neck. In acute eczema, the rash can be weepy and oozy. However, in chronic eczema, the rash is raised and thick and this can resemble psoriasis. In general, most children will outgrow their eczema and improve as they grow older, although about 20% may continue to have eczema in adulthood.
Psoriasis commonly presents with thick, scaly, well-directed, red patches that can often also be itchy. The scalp, elbow, and knees are some of the common areas that are affected. The lesions of psoriasis are usually thicker and scalier than the rash seen in eczema. Psoriasis is a chronic disease which is persistent. While there may be periods of exacerbation and remission, you do not outgrow psoriasis.
The immune system is important in the development of eczema and psoriasis, but the immune pathways are very different for both conditions. It is general, if you have eczema, you are less likely to have psoriasis. However, I have seen cases where both conditions co-exist in the same individual.
