Differential Diagnosis for a Painful Lump Behind the Left Ear
Single Most Likely Diagnosis
- Acute mastoiditis: This condition is an infection of the mastoid bone, which is located behind the ear. It often presents with pain, swelling, and a lump in the affected area, making it a likely diagnosis given the patient's symptoms.
Other Likely Diagnoses
- Infected sebaceous cyst: A sebaceous cyst can become infected, leading to pain, swelling, and a lump. The location behind the ear is a common site for sebaceous cysts.
- Lymphadenitis: Inflammation of the lymph nodes, which can be caused by infection or other conditions, can present as a painful lump behind the ear.
- Furuncle or carbuncle: A furuncle (boil) or carbuncle (cluster of boils) can occur behind the ear, especially if the area is prone to sweating or irritation, leading to a painful lump.
Do Not Miss Diagnoses
- Mastoid abscess: Although less common, a mastoid abscess is a serious complication of mastoiditis that requires prompt treatment. It can present similarly to mastoiditis but may have additional symptoms like fever and severe pain.
- Temporal bone osteomyelitis: An infection of the temporal bone, which can spread from nearby structures, is a rare but serious condition that could present with pain and a lump behind the ear.
- Parotid gland tumor: Although less likely, a tumor of the parotid gland, which is located near the ear, could present as a lump. While most parotid tumors are benign, some can be malignant.
Rare Diagnoses
- Branchial cleft cyst: A congenital anomaly that can present as a lump along the side of the neck or behind the ear, especially if it becomes infected.
- First branchial cleft anomaly: Similar to a branchial cleft cyst but can involve the ear and present with a lump or discharge.
- Eagle syndrome: A condition caused by an elongated styloid process or calcified stylohyoid ligament, which can cause pain in the ear and throat area, though it's less commonly associated with a lump behind the ear.