PLAID/APLAID Syndrome
PLCG2 associated antibody deficiency and immune dysregulation (PLAID) is a complex dominantly inherited disease characterized almost universally by cold urticaria (hives), and variably by recurrent bacterial infection, autoimmunity and skin granuloma formation. Several striking phenotypes can emerge from this disease, and the pathophysiology leads to a complex mix of loss and gain of function in cellular signalling.
Characteristics of PLCG2-associated antibody deficiency and immune dysregulation
Symptoms
Some individuals with PLAID can develop a burn-like rash at birth in areas more likely to get cold, such as the nose. People with PLAID may also have recurrent bacterial infections, autoimmune symptoms and an increased likelihood of developing an autoimmune disorder, and a burning sensation in the throat when eating cold foods.
Autoinflammation and PLCG2-associated antibody deficiency and immune dysregulation (APLAID) is an autosomal dominant systemic disorder characterized by recurrent blistering skin lesions with a dense inflammatory infiltrate and variable involvement of other tissues, including joints, eyes, and the gastrointestinal tract. Affected individuals have a mild humoral immune deficiency associated with recurrent sinopulmonary infections (involving, or affecting the paranasal sinuses and the airway of the lungs), but no evidence of circulating autoantibodies.
The symptoms were partially responsive to an IL1 inhibitor and high-dose corticosteroids.
Treatment
No treatments that target the underlying cause of PLAID and PLAID-like diseases exist, so people with PLAID are advised to avoid allergic triggers by warming rapidly after showers, avoiding drafts, and towelling off sweat. Antihistamines are used to treat allergic reactions.
Watch a time-lapse video from the NIH. In this video, once can see infrared footage of the inflammatory response in a person with cold allergy, a condition known as cold urticaria.