Wound Care Certified Certification (WCC) Practice Exam

What is the MOST likely etiology of a purplish rash that turns blue-gray with fluid-filled blisters?

1. Cellulitis

2. Necrotizing fasciitis

3. Psoriasis

4. Herpes zoster

The correct answer is: Necrotizing fasciitis

The purplish rash that transforms into a blue-gray hue alongside the presence of fluid-filled blisters suggests a serious underlying condition. The most likely etiology being necrotizing fasciitis aligns with its hallmark characteristics. This condition is typically caused by a bacterial infection that rapidly spreads through the fascial planes of the skin, leading to tissue necrosis. As the infection progresses, the skin can exhibit color changes due to compromised blood flow and tissue death, which often manifests as a purplish discoloration. The formation of fluid-filled blisters can occur as a result of the inflammatory process and tissue breakdown associated with the infection. Necrotizing fasciitis is considered a medical emergency due to its aggressive nature and the potential for systemic complications. In contrast, cellulitis is usually characterized by redness and warmth but does not typically lead to the formation of significant blisters or the specific color changes seen in necrotizing fasciitis. Psoriasis often presents with silvery scales and does not fit the description of a blistering rash. While herpes zoster can cause blistering, the initial presentation is more localized and follows a dermatomal pattern, rather than the widespread and severe indications present in necrotizing fasciitis. Thus, necrot