FMGE 2022 — Dermatology

Question 1: Which of the following is the causative agent for acne fulminans?

• A. Staphylococcus aureus
• B. Malassezia furfur
• C. Propionibacterium acnes (Cutibacterium acnes) (Correct Answer)
• D. Streptococcus pyogenes

Explanation: ***Propionibacterium acnes (Cutibacterium acnes)*** - **Acne fulminans** is a severe, ulcerative form of acne that is considered an **autoinflammatory syndrome** rather than a simple bacterial infection - While the exact etiology remains unclear, ***Cutibacterium acnes*** (formerly *Propionibacterium acnes*) plays a significant role in the pathophysiology - It is believed that acne fulminans may result from a **hypersensitivity reaction to *C. acnes* antigens** or an exaggerated immune response to the bacterium - *C. acnes* is the **most relevant microorganism** associated with all forms of acne, including acne vulgaris and severe variants like acne fulminans - Treatment often includes systemic corticosteroids (to control inflammation) combined with isotretinoin *Staphylococcus aureus* - *Staphylococcus aureus* causes **bacterial skin infections** such as folliculitis, impetigo, furuncles, and cellulitis - While secondary bacterial superinfection with *S. aureus* can complicate acne lesions, it is **not the primary organism** associated with acne fulminans *Malassezia furfur* - *Malassezia furfur* (now classified as *Malassezia globosa* or *M. restricta*) is a **yeast** that causes **pityriasis versicolor** and **Malassezia folliculitis** (also called fungal acne or pityrosporum folliculitis) - It is **not involved** in the pathogenesis of acne vulgaris or acne fulminans *Streptococcus pyogenes* - *Streptococcus pyogenes* is a common cause of **streptococcal infections** including pharyngitis, impetigo, erysipelas, and cellulitis - It is **not associated** with acne or acne fulminans pathogenesis