Differential Diagnosis for 26 yo m with Groin Rash Spreading
- Single most likely diagnosis
- Tinea cruris (jock itch): This is a common fungal infection in the groin area, especially in young males, characterized by a spreading rash. It's often associated with itching, redness, and a well-demarcated border.
- Other Likely diagnoses
- Contact dermatitis: This could be due to an allergic reaction or irritant causing a rash in the groin area. It might spread depending on the exposure to the causative agent.
- Eczema (atopic dermatitis): Although less common in the groin, eczema can cause a rash that spreads, especially if not properly managed.
- Intertrigo: A skin inflammation caused by friction and moisture, common in skin folds like the groin, leading to a spreading rash.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Cellulitis: A bacterial skin infection that can spread rapidly and become serious if not treated promptly. It's characterized by redness, swelling, warmth, and sometimes fever.
- Lyme disease: Although less common in the groin, Lyme disease can cause a spreading rash (erythema migrans) and is crucial to diagnose early to prevent long-term complications.
- Syphilis (secondary): This can cause a variety of skin rashes, including in the groin area, and is critical to diagnose due to its potential for serious complications if left untreated.
- Rare diagnoses
- Pemphigus: A group of rare skin disorders that cause blistering of the skin and mucous membranes, which could potentially start in the groin area.
- Mycosis fungoides (cutaneous T-cell lymphoma): A rare type of skin cancer that can cause skin lesions, including in the groin area, though it's more common in older adults.
- Granuloma inguinale (donovanosis): A rare bacterial infection that causes ulcerative lesions in the genital area, which could be mistaken for a spreading rash.