Porokeratosis vs Ringworm
How to tell the difference — key features compared side by side.
Feature
Porokeratosis
Ringworm
Category
Pre-cancerous
Common
Key feature
Ring-like lesions with a distinctive raised ridge border. 7-11% lifetime SCC risk.
Fungal infection - not a worm. Creates circular red patches with clearing centers. Contagious but easily treated.
Risk factors
Genetic predisposition; Immunosuppression; Chronic sun exposure (DSAP variant)
Direct contact with infected people or animals; Contact sports (wrestling is high-risk); Shared changing rooms, showers, gym equipment
Action needed
Ring-like skin lesions with a raised border
Ring-shaped rash not improving after 2 weeks of OTC antifungal
Porokeratosis
Porokeratosis is characterized by well-defined patches surrounded by a distinctive thin raised ridge (cornoid lamella) - a column of abnormal keratin.
Read full guide →Ringworm
Ringworm (tinea corporis) is a fungal infection of the skin caused by dermatophyte fungi. Despite its name, no worm is involved - the name comes from the characteristic ring-shaped rash with a raised, scaly border and clearing center.
Read full guide →Does yours look more like porokeratosis?
Quick self-check
Does this look like porokeratosis? Answer 2 questions.
Does the lesion have a ring shape with a thin raised ridge border?
Has it been present for months to years?
Still not sure?
Our full ABCDE checker evaluates 5 clinical criteria dermatologists use.
Full ABCDE check →