Diagnosing Rosacea: A Phenotype-Based Approach
Rosacea is diagnosed primarily by the presence of either persistent centrofacial erythema with periodic intensification by trigger factors OR phymatous changes, as these two features are independently diagnostic according to the Global ROSacea COnsensus (ROSCO) panel. 1
Diagnostic Criteria
Diagnostic Features (Either one is sufficient for diagnosis)
- Persistent centrofacial erythema with periodic intensification - This is considered a minimum diagnostic feature 1, 2
- Phymatous changes - Independently diagnostic, characterized by skin thickening, irregular surface nodularities, and enlargement (particularly of the nose) 1
Major Features (Not individually diagnostic)
These support the diagnosis when present with diagnostic features:
- Flushing/transient erythema
- Telangiectasia
- Inflammatory papules and pustules
- Ocular manifestations
Minor Features
- Burning or stinging sensations
- Edema
- Dry sensation
- Ocular symptoms (in absence of ocular signs)
Location Considerations
- Centrofacial location (cheeks, nose, chin, forehead) is essential for diagnosis 1
- Bilateral facial involvement is typical but not essential 1
Severity Assessment Dimensions
For accurate documentation and treatment planning, assess severity of each feature:
Flushing/Transient Erythema
- Intensity
- Frequency of episodes
- Duration of episodes
- Area of involvement
- Associated symptoms
Persistent Erythema
- Intensity
- Extent
Inflammatory Papules/Pustules
- Number of lesions
- Extent of facial involvement
- Intensity of lesional erythema
Telangiectasia
- Size of vessels
- Extent of involvement
Phymatous Changes
- Inflammation
- Cutaneous thickening
- Deformation
- Affected sites
Differential Diagnosis
Rosacea must be distinguished from:
- Acne vulgaris
- Seborrheic dermatitis
- Lupus erythematosus
- Contact dermatitis
- Perioral dermatitis 2
Special Considerations
Ocular Rosacea
- May present as blepharoconjunctivitis or blepharokeratoconjunctivitis
- Look for recurrent chalazia, punctate erosions, peripheral keratitis, and meibomian gland disease 2
- Ocular findings may precede cutaneous manifestations, especially in children 2
Skin Type Considerations
- Diagnosis can be challenging in patients with darker skin tones
- In darker skin, diagnosis may rely more on symptoms of irritation and hyperpigmentation rather than visible erythema 2
Epidemiology
- More prevalent in women but can be more severe in men 2
- Peak onset occurs in persons in their 40s and 50s 3
- Affects up to 10% of the world population, especially fair-skinned individuals 4
Common Diagnostic Pitfalls
Focusing only on current presentation - Rosacea is chronic with fluctuating symptoms; understanding the disease course over time is essential 2
Overlooking psychosocial impact - Always assess quality of life effects, including social embarrassment, emotional distress, and self-esteem issues 2
Missing ocular involvement - Always examine for ocular manifestations even when cutaneous features predominate 2
Confusing with acne - Unlike acne, rosacea typically lacks comedones and has more prominent erythema and telangiectasia 5
Neglecting trigger identification - Identifying and documenting triggers (sun exposure, spicy foods, alcohol, temperature extremes) is crucial for management 2
By following this phenotype-based diagnostic approach, clinicians can accurately identify rosacea and its specific manifestations, leading to more targeted and effective treatment strategies.