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 alba is a common skin disorder in children. The exact cause is unknown. However, it is thought that the condition may be associated with eczema, a common skin disorder that causes scaly, itchy rashes. People with pityriasis alba develop red, flaky patches on their skin that are round or oval in shape.eople with pityriasis alba experience round or oval patches of pale pink or red skin. The patches may appear on the following parts of the body: face (most common), upper arms, neck, and upper middle of the body.