Mastoiditis is a topic covered in the 5-Minute Clinical Consult.

To view the entire topic, please or purchase a subscription.

Medicine Central™ is a quick-consult mobile and web resource that includes diagnosis, treatment, medications, and follow-up information on over 700 diseases and disorders, providing fast answers—anytime, anywhere. Explore these free sample topics:

Medicine Central

-- The first section of this topic is shown below --


An inflammatory process of the mastoid air cells and/or posterior process of the temporal bone, most commonly a suppurative complication of acute otitis media (AOM)


  • Clinical manifestations of mastoiditis typically appear 3 weeks after the first middle ear symptoms.
  • Stiffness and thickening of the tympanic membrane (TM) is common.
  • Acute mastoiditis: symptoms <1 month in duration; subdivided according to the pathologic stages:
    • Acute mastoiditis with periostitis (incipient mastoiditis): purulent material in the mastoid cavities
    • Coalescent mastoiditis (acute mastoid osteitis): destruction of the thin bony septae between air cells; followed by the formation of abscess cavities pus dissecting into adjacent areas
  • Masked mastoiditis (subacute mastoiditis): low grade, persistent infection with destruction of the bony septae between air cells; occurs in patients with persistent middle ear effusion or recurrent episodes of inadequately treated AOM
  • Chronic mastoiditis: associated with failed treatment of chronic otitis media. Often associated with cholesteatoma; symptoms last months to years.


Highest incidence in children <2 years

  • Routine prescription of antibiotics and routine childhood immunizations have reduced the number of cases of AOM and mastoiditis.

1 to 4 cases per 100,000 children per year (1)

Etiology and Pathophysiology

  • Subclinical stage begins with AOM and inflammation of mastoid air cells.
  • Obstruction of the aditus ad antrum (connecting the tympanic cavity and mastoid)
    • Blocks outflow tract of mastoid air cells
    • Edema and accumulation of purulent material with penetration of periosteum (acute mastoiditis with periosteitis)
  • Increased pressure from fluid within the air cells leads to destruction of bony septae (acute mastoid osteitis/acute coalescent mastoiditis).
  • Acute mastoid osteitis can spread to adjacent areas in head and neck with abscess formation:
    • Subperiosteal abscess (most common complication), Bezold abscess, suppurative labyrinthitis, suppurative CNS complications
  • AOM: Haemophilus influenzae, Streptococcus pneumoniae
  • Acute mastoiditis: S. pneumoniae (most common), Streptococcus pyogenes, H. influenzae, Staphylococcus aureus (including methicillin-resistant S. aureus [MRSA])
  • Chronic mastoiditis: Pseudomonas aeruginosa, S. aureus, Enterobacteriaceae, anaerobic bacteria, polymicrobials (2)

No known genetic pattern

Risk Factors

  • Cholesteatoma
  • Recurrent AOM or chronic suppurative otitis media
  • Immunocompromised state

General Prevention

  • Ensure appropriate vaccinations (particularly pneumococcal vaccine).
  • Referral to ENT for chronic otitis media
  • Appropriate diagnosis and treatment of AOM
  • Prevent recurrent AOM.
  • Treat chronic eustachian tube dysfunction (pressure equalization tubes).
  • Early diagnosis of cholesteatoma

-- To view the remaining sections of this topic, please or purchase a subscription --