Differential Diagnosis for Circular Skin Lesion
Single Most Likely Diagnosis
- Tinea corporis (ringworm): a common fungal infection that causes circular, itchy, and scaly skin lesions, often seen in children and adolescents.
Other Likely Diagnoses
- Eczema (nummular dermatitis): a type of skin inflammation that can cause circular, itchy, and scaly lesions, often triggered by dry skin or allergies.
- Psoriasis: a chronic skin condition that can cause circular, scaly, and inflamed lesions, often accompanied by other symptoms like joint pain or nail changes.
- Contact dermatitis: a skin reaction to an allergen or irritant that can cause circular, itchy, and inflamed lesions.
Do Not Miss Diagnoses
- Lyme disease: a bacterial infection transmitted by ticks that can cause a circular, expanding skin lesion (erythema migrans), which can lead to serious complications if left untreated.
- Malignancy (e.g., basal cell carcinoma, squamous cell carcinoma): although rare, skin cancers can present as circular lesions, and early detection is crucial for effective treatment.
Rare Diagnoses
- Sarcoidosis: a systemic disease that can cause circular, skin lesions, often accompanied by other symptoms like lung or eye involvement.
- Leishmaniasis: a parasitic infection that can cause circular, skin lesions, often seen in travelers to endemic areas.
- Granuloma annulare: a rare skin condition that causes circular, bumpy lesions, often seen in children and adolescents.