Differential Diagnosis for Pump with Pus on Scalp
- Single most likely diagnosis
- Furuncle or Carbuncle: This is the most likely diagnosis given the description of a "pump with pus" on the scalp. A furuncle (boil) is an infection of the hair follicle, and when several furuncles merge, they form a carbuncle. Both conditions are typically caused by Staphylococcus aureus and present with a painful, pus-filled nodule or mass.
- Other Likely diagnoses
- Abscess: An abscess is a collection of pus that has built up within the tissue of the body, which could occur on the scalp. It's similar to a furuncle or carbuncle but might not be centered on a hair follicle.
- Folliculitis: This is an inflammatory condition affecting the hair follicles, often caused by bacterial infection. It can present with pus-filled bumps on the scalp.
- Infected epidermoid cyst: These are benign cysts that can become infected, leading to a painful, pus-filled lesion that could resemble a "pump with pus."
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Meningitis or brain abscess (especially if there's a history of trauma or the patient shows signs of neurological deficit): Although less common, an infection on the scalp could potentially spread to the brain, especially if it's related to a traumatic injury or if the patient has a compromised immune system.
- Osteomyelitis of the skull: This is an infection of the bone, which could occur if the infection spreads from the scalp to the underlying bone.
- Rare diagnoses
- Kerion: A severe form of tinea capitis (ringworm of the scalp) that can cause a painful, pus-filled mass. It's more common in children.
- Mycetoma: A chronic, granulomatous infection of the skin and subcutaneous tissue caused by fungi or bacteria, which can present with pus-filled lesions. It's rare in most parts of the world but should be considered in endemic areas or in patients who have traveled to such areas.