Differential Diagnosis for a Large Red Ear
- Single most likely diagnosis
- Cellulitis: This is a common condition characterized by redness, swelling, and warmth of the skin, often caused by bacterial infection. The ear is a typical location for cellulitis due to its exposed nature and potential for minor trauma that can introduce bacteria.
- Other Likely diagnoses
- Otitis externa (Swimmer's ear): An infection of the outer ear canal, often caused by bacteria or fungi, leading to redness, swelling, and sometimes discharge. The ear's appearance can become red and swollen, fitting the description.
- Allergic contact dermatitis: An allergic reaction to substances like earrings, especially nickel, can cause redness, itching, and swelling around the earlobe.
- Seborrheic dermatitis: A skin condition causing scaly patches, red skin, and stubborn dandruff, which can affect the outer ear.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Erysipelas: A type of skin infection that can cause redness and swelling, typically affecting the face or lower extremities but can occur on the ear. It's crucial to differentiate from cellulitis due to its potential for serious complications.
- Necrotizing otitis externa: A severe infection of the outer ear that can spread to the skull base, more common in diabetic or immunocompromised patients. Early recognition is critical due to its potential for severe morbidity and mortality.
- Relapsing polychondritis: An autoimmune disorder that can cause cartilage inflammation, including that of the ear, leading to redness, swelling, and potential destruction of the cartilage.
- Rare diagnoses
- Granuloma faciale: A rare skin condition characterized by single or multiple, benign, reddish-brown plaques or nodules, typically on the face, which could potentially affect the ear area.
- Angiosarcoma of the ear: A rare and aggressive form of cancer that originates from the lining of blood vessels and can present as a red, bleeding lesion on the ear.