Merck Manual

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Richard T. Miyamoto

, MD, MS, Indiana University School of Medicine

Reviewed/Revised Mar 2022 | Modified Sep 2022
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Mastoiditis is a bacterial infection of the mastoid air cells, which typically occurs after acute otitis media. Symptoms include redness, tenderness, swelling, and fluctuation over the mastoid process, with displacement of the pinna. Diagnosis is clinical. Treatment is with antibiotics, such as ceftriaxone, and mastoidectomy if drug therapy alone is not effective.

In acute purulent otitis media Otitis Media (Acute) Acute otitis media is a bacterial or viral infection of the middle ear, usually accompanying an upper respiratory infection. Symptoms include otalgia, often with systemic symptoms (eg, fever... read more Otitis Media (Acute) , inflammation often extends into the mastoid antrum and air cells in the temporal bone, resulting in fluid accumulation. In a few patients, bacterial infection develops in the collected fluid, typically with the same organism causing the otitis media; pneumococcus is most common. Mastoid infection can cause osteitis of the septae, leading to coalescence of the air cells.

The infection may decompress through a perforation in the tympanic membrane or extend through the lateral mastoid cortex, forming a postauricular subperiosteal abscess. Rarely, it extends centrally, causing a temporal lobe abscess or a septic thrombosis of the lateral sinus. Occasionally, the infection may erode through the tip of the mastoid and drain into the neck (called a Bezold abscess).

Symptoms and Signs of Mastoiditis

Diagnosis of Mastoiditis

  • Clinical evaluation

  • Rarely computed tomography (CT)

Diagnosis of mastoiditis is clinical. CT is usually done, especially if an intratemporal or intracranial complication is suspected, to confirm the diagnosis and show the extent of the infection. Any middle ear drainage is sent for culture and sensitivity. Tympanocentesis for culture purposes can be done if no spontaneous drainage occurs. Complete blood count (CBC) and erythrocyte sedimentation rate (ESR) may be abnormal but are neither sensitive nor specific and add little to the diagnosis.

Treatment of Mastoiditis

  • IV ceftriaxone

IV antibiotic treatment is initiated immediately with a drug that provides central nervous system penetration, such as ceftriaxone 1 to 2 g (children, 50 to 75 mg/kg) once a day continued for 2 weeks; vancomycin or linezolid are alternatives. Oral treatment with a quinolone may be acceptable. Subsequent antibiotic choice is guided by culture and sensitivity test results.

A subperiosteal abscess usually requires a simple mastoidectomy, in which the abscess is drained, the infected mastoid cells are removed, and drainage is established from the antrum of the mastoid to the middle ear cavity.

Drugs Mentioned In This Article

Drug Name Select Trade
Ceftrisol Plus, Rocephin
FIRVANQ, Vancocin, Vancocin Powder, VANCOSOL
Zyvox, Zyvox Powder, Zyvox Solution
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NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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