IgA deficiency, a selective lack of immunoglobulin A (IgA). The most common type of immunoglobulin deficiency, it occurs in about 1 in 400 individuals. IgA is a major antibody in the saliva and in the mucous membranes of the intestines and the bronchi. It protects against bacterial and viral infections.gA deficiency, a selective lack of immunoglobulin A (IgA). The most common type of immunoglobulin deficiency, it occurs in about 1 in 400 individuals. IgA is a major antibody in the saliva and in the mucous membranes of the intestines and the bronchi. It protects against bacterial and viral infections.
Pityriasis rubra pilaris (PRP) refers to a group of skin conditions that cause constant inflammation and scaling of the skin. People with PRP have reddish, scaly patches that may occur everywhere on the body, or only on certain areas.
Pityriasis rosea. Pityriasis rosea is a common, usually mild, skin rash that often begins with a large, scaly, pink patch of skin on the chest or back. The patch is usually followed by additional pink patches of skin. There is an itching of skin lesions and redness or inflammation of the skin. rash indicates an abnormal change in skin colour or texture. Some skin rashes may be caused by a virus, such as chicken pox, shingles or measles. Rashes are often caused by skin irritation, which can have many causes, such as an allergic reaction, or sting from a plant such as a stinging nettle.