What is the term for urticaria involving subcutaneous tissues that can present as swelling in critical areas?

Angioedema is the correct term for urticaria that involves subcutaneous tissues and can lead to swelling in critical areas. It typically presents as more profound swelling compared to urticaria and can affect areas such as the face, lips, tongue, and throat. This can be particularly concerning because swelling in the respiratory tract can lead to airway obstruction, posing a significant medical risk.

In contrast, atopic dermatitis refers to a chronic inflammatory skin condition characterized by dry, itchy skin and is primarily confined to the epidermis rather than involving swelling of the deeper tissues. Contact dermatitis is an inflammatory skin reaction resulting from exposure to an allergen or irritant, resulting primarily in localized red and itchy rashes without significant deep swelling. Impetigo, on the other hand, is a bacterial skin infection that typically presents with crusted lesions and is not related to the swelling associated with angioedema. Understanding the specifics of these conditions helps differentiate them based on clinical presentation and depth of skin involvement.