Mastoiditis is an infection of the mastoid bone of the skull. The mastoid bone is located just behind the ear.
Mastoiditis is most often caused by a middle ear infection (acute otitis media). The infection may spread from the ear to the mastoid bone. The bone has a honeycomb-like structure that fills with infected material and may break down.
The condition is most common in children. Before antibiotics, mastoiditis was one of the leading causes of death in children. The condition does not occur very often today. It is also much less dangerous.
Mastoiditis may be hard to treat because the medicine may not reach deeply into the bone. The condition sometimes requires repeated or long-term treatment. The infection is treated with antibiotic injections, followed by antibiotics taken by mouth.
Surgery to remove part of the bone and drain the mastoid (mastoidectomy) may be needed if antibiotic treatment does not work. Surgery to drain the middle ear through the eardrum (myringotomy) may be needed to treat the middle ear infection.
Mastoiditis can be cured. However, it may be hard to treat and may come back.
When to Contact a Medical Professional
Contact your health care provider if you have symptoms of mastoiditis.
Also call if:
- You have an ear infection that does not respond to treatment or is followed by new symptoms.
- Your symptoms do not respond to treatment.
- You notice any facial asymmetry.
Prompt and thorough treatment of ear infections reduces the risk for mastoiditis.
Matlock AG, Pfaff JA. Otolaryngology. Matlock AG, In: Walls RM, Hockberger RS, Gausche-Hill M, eds. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 58.
Pelton SI. Otitis externa, otitis media, and mastoiditis. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 61.
Review Date 5/30/2022
Updated by: Josef Shargorodsky, MD, MPH, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.