Rosacea
A chronic inflammatory dermatosis characterized by facial erythema, telangiectasia, and inflammatory lesions.
Pathophysiology
The exact etiology is multi-factorial, involving dysregulation of the innate immune system (elevated cathelicidin LL-37), neurovascular hyper-reactivity, and potential microbiome alterations (e.g., Demodex folliculorum proliferation).
Clinical Subtypes
Erythematotelangiectatic (ETR)
Persistent erythema with transient flushing. Prominent telangiectasias. Skin is often highly sensitive and stings upon application of topical products.
Papulopustular (PPR)
Persistent central facial erythema with transient, central facial papules or pustules. Can resemble acne but lacks comedones.
Phymatous
Thickening skin, irregular surface nodularities, most commonly on the nose (rhinophyma).
Ocular
Watery or bloodshot appearance, foreign body sensation, burning or stinging.
Management Protocols
First-line defense involves barrier repair and strict avoidance of triggers (UV radiation, heat, spicy foods, alcohol).
Pharmacological Interventions
- Azelaic Acid (15-20%): Reduces inflammation and reactive oxygen species. First-line for PPR.
- Metronidazole (0.75-1%): Anti-inflammatory effects.
- Ivermectin (1%): Anti-inflammatory and anti-parasitic (targets Demodex).
- Brimonidine / Oxymetazoline: Alpha-adrenergic agonists for temporary vasoconstriction of ETR.