Differential Diagnosis for Rashes Resembling Tinea Corporis
Single Most Likely Diagnosis
- Tinea corporis: This is the most likely diagnosis due to the characteristic ring-shaped appearance of the rash, which is a hallmark of tinea corporis, a fungal infection of the skin.
Other Likely Diagnoses
- Nummular dermatitis: This condition presents with coin-shaped patches of eczema, which can resemble tinea corporis. It's often seen in individuals with a history of atopic dermatitis.
- Granuloma annulare: A benign skin condition characterized by ring-shaped lesions, which can be mistaken for tinea corporis. It's more common in children and young adults.
- Pityriasis rosea: Although it typically starts with a herald patch, the subsequent rash can sometimes be confused with tinea corporis due to its ring-shaped appearance.
Do Not Miss Diagnoses
- Lyme disease (erythema migrans): The initial rash of Lyme disease can resemble tinea corporis, making it crucial to consider this diagnosis, especially in individuals who have been exposed to ticks.
- Sarcoidosis: Cutaneous sarcoidosis can present with various skin lesions, including those that resemble tinea corporis. Missing this diagnosis could lead to delayed treatment of systemic sarcoidosis.
- Cutaneous lupus erythematosus: This autoimmune condition can cause skin lesions that might be mistaken for tinea corporis, emphasizing the importance of considering it to avoid missing a systemic autoimmune disease.
Rare Diagnoses
- Erythema annulare centrifugum: A rare condition characterized by annular (ring-shaped) erythema, which can be mistaken for tinea corporis. It's often associated with underlying conditions such as infections or malignancies.
- Subacute cutaneous lupus erythematosus: A less common form of cutaneous lupus that can present with annular polycyclic lesions, resembling tinea corporis.
- Necrolytic migratory erythema: A rare skin condition associated with glucagonoma syndrome, characterized by necrolytic migratory erythema that can mimic tinea corporis.