American Board of Internal Medicine (ABIM) Certification Practice Exam

Pathergy, a positive response to skin trauma, is associated with which condition?

1. Multiple sclerosis

2. Behçet syndrome

3. Rheumatoid arthritis

4. Lupus erythematosus

The correct answer is: Behçet syndrome

The association between pathergy and Behçet syndrome is well established in medical literature. Pathergy describes a hypersensitive reaction to minor trauma or injury to the skin, resulting in the formation of pustules or ulcers at the site of injury. This phenomenon is particularly characteristic of Behçet syndrome, which is a systemic vasculitis that often presents with recurrent oral and genital ulcers, skin lesions, and uveitis. In Behçet syndrome, the mechanism of pathergy is thought to involve an exaggerated inflammatory response due to an underlying dysregulation of immune pathways. When the skin is traumatized, the immune system reacts more intensely than normal, highlighting a distinctive clinical feature of this condition. Pathergy testing, where a small needle prick is applied to the skin to observe for a reaction, is often utilized diagnostically to support the diagnosis of Behçet syndrome. Other conditions listed, while they may involve skin manifestations or immune dysregulation, do not consistently exhibit pathergy as a hallmark sign. For example, multiple sclerosis, rheumatoid arthritis, and lupus erythematosus have different immunological profiles and clinical features that do not include the notable pathergic response seen in Behçet syndrome. Therefore, when considering the specific association of