Wound, Ostomy and Continence Nurses Society (WOCN) Practice Exam

What are bullous lesions primarily caused by?

1. Infection

2. Allergic reactions targeting anchor fibrils

3. Sun damage

4. Genetic predisposition only

The correct answer is: Allergic reactions targeting anchor fibrils

Bullous lesions are primarily caused by allergic reactions that target anchor fibrils, which are structural proteins that help attach the epidermis to the dermis in the skin. These reactions can lead to the formation of blisters, which are the hallmark of bullous lesions. Conditions such as bullous pemphigoid and epidermolysis bullosa involve autoimmune mechanisms where the body reacts against these proteins, resulting in inflammatory responses that create fluid-filled spaces between skin layers and lead to blister formation. The other options, while they may contribute to skin changes, do not specifically target anchor fibrils and the resultant blistering effect. For example, infections can cause various skin lesions, but they are not the primary cause of bullous lesions specifically. Sun damage and genetic predisposition may lead to various skin conditions, but without the direct involvement of an allergic mechanism targeting structural skin proteins, these factors are not the cause of the bullous appearance. Therefore, understanding the role of immune-mediated mechanisms in the formation of bullous lesions is essential in distinguishing the underlying causes of these lesions.