Differential Diagnosis for Rear Head Bumps
Single Most Likely Diagnosis
- Furuncle or Carbuncle: The presence of a white head, pus, and mild redness and tenderness on palpation suggests a furuncle (boil) or carbuncle, which are infections of the hair follicle. The fact that one bump was popped and had pus supports this diagnosis.
Other Likely Diagnoses
- Cyst (Epidermoid or Sebaceous): The closed, non-tender, and non-red bump could be a benign cyst, such as an epidermoid or sebaceous cyst. These cysts can become infected and resemble a furuncle.
- Folliculitis: An inflammation of the hair follicle, which can cause bumps, redness, and tenderness, similar to the symptoms described.
- Keratosis Pilaris: A harmless condition that causes small, rough bumps on the skin, but it's less likely given the presence of pus and tenderness.
Do Not Miss Diagnoses
- Meningitis or Subcutaneous Abscess with Intracranial Extension: Although rare, it's crucial to consider the possibility of an abscess or infection that could extend into the intracranial space, especially if there are signs of neurological deficit or severe headache.
- Osteomyelitis: An infection of the bone, which could cause bumps, redness, and tenderness, especially if the infection started from a contiguous site.
Rare Diagnoses
- Pilar Cyst (Trichilemmal Cyst): A rare type of benign cyst that originates from the hair follicle and can cause a bump.
- Dermatofibroma: A rare, benign skin growth that can cause a bump, but it's usually firm and non-tender.
- Neurofibroma: A rare, benign tumor of the nerve tissue that can cause a bump, but it's usually firm and non-tender.
Workup and Treatment
The workup may include:
- Complete blood count (CBC) to check for signs of infection
- Blood cultures to rule out bacteremia
- Imaging studies (e.g., CT or MRI) if there's suspicion of intracranial extension or osteomyelitis
- Incision and drainage of the abscess (if present)
Treatment may involve:
- Antibiotics for bacterial infections
- Warm compresses to promote drainage
- Pain management with over-the-counter pain relievers
- Follow-up appointments to monitor the resolution of the bumps and to rule out any complications.