001. Isolated Capillary Malformation (Port-Wine Stain)
Quick Summary: The classic port-wine stain is the most common vascular birthmark. It is present at birth, low-flow, does not shrink on its own, and does not become cancerous.
- Also Known As: Port-wine stain (PWS), Port-wine birthmark, Capillary malformation (CM), Nevus flammeus
- ISSVA Classification: Vascular Malformation → Slow-Flow → Capillary → Isolated
- ICD-10 Code:
Q82.5 - Genetic Driver: Somatic mosaic GNAQ mutation
1. What You See
A flat, reddish-pink to deep purple patch on the skin present from birth. Does not blanch completely or disappear with crying.
2. What You Feel
In childhood, little to no sensation. In adulthood, mild warmth, heaviness, or sensitivity if thickened.
🚨 Red Flag Indicators (Changes Diagnosis)
- Forehead / Upper Eyelid: Evaluate for Sturge-Weber Syndrome
- Limb Enlargement: Evaluate for Klippel-Trenaunay Syndrome
- Warmth / Bruit / Pulse: Evaluate for Parkes Weber or AVM