What is mastoiditis

Mastoiditis is a serious bacterial infection that affects of the membranes lining the mastoid bone in the skull, found behind the ear ¹. Mastoiditis is a serious infection and should be diagnosed and treated quickly with antibiotics. You may need to go to hospital so antibiotics can be given directly into a vein through a drip.

In some cases, surgery may be needed to either:

• drain the middle ear (a myringotomy)
• remove part of the mastoid bone (mastoidectomy)

Mastoiditis is more common in children. Most people with mastoiditis recover quickly and have no complications as long as the mastoiditis is diagnosed and treated quickly.

The main symptom of mastoiditis is pain behind the ear, sometimes accompanied by swelling and fever too. Mastoiditis must be treated with antibiotics to prevent the infection from spreading to the bone.

If the bacteria spread, they can cause meningitis. Typical symptoms of meningitis include a high fever, severe headache, nausea, a stiff neck, sleepiness and confusion. This complication is life-threatening and must be treated immediately.

Figure 1. Mastoiditis

Footnote: A 60-year-old man presented with a 10-year history of intermittent otorrhea of the right ear and a 2-month history of swelling of the right postauricular area. Physical examination revealed postauricular swelling with an erythematous skin change behind the right ear (Panel A, arrow). Otoscopic examination revealed a perforation in the lower part of the tympanic membrane, with discharge (Panel B, arrow). Audiometry revealed conductive hearing loss in the right ear. High-resolution computed tomography of the temporal bone (axial view) revealed high soft-tissue density lesions in the right tympanic cavity and in the mastoid air cells. Multifocal cortical defects were noted on the outer surface of the temporal bone and on the inner aspect facing the sigmoid sinus (Panel C, arrows). A diagnosis of chronic suppurative otitis media complicated by acute mastoiditis was made. This should be differentiated from other infections, such as parotitis, postauricular cellulitis, and lymphadenitis. The patient underwent tympanoplasty with mastoidectomy. During surgery, abundant granulation tissues filling the mastoid air cells and tympanic cavity were found and removed. The postauricular swelling and tenderness subsided gradually after treatment. His hearing also improved.

Acute mastoiditis

Acute mastoiditis is the most common complication of acute otitis media and is largely a disease of childhood ³, which often requires hospitalization and intravenous antibiotics and sometimes requires surgery ⁴. It is estimated that in every 50,000 child with acute otitis media 1 child develops mastoiditis. In the pre-antibiotic era, approximately 2–6% of acute otitis media patients developed suppurative intra-cranial complications, with a fatal outcome in up to 75% of cases ⁵. When mastoiditis and acute otitis media occur concurrently, sometimes the term acute otomastoiditis is used ⁶. When mucoperiosteal involvement evolves into bony involvement with resorption of mastoid air cell bony septae, the condition should be referred to as coalescent mastoiditis.

Acute mastoiditis is most frequently due to bacterial infections, with Streptococcus pneumoniae and Haemophilus influenzae accounting for 65-80% of cases ⁶.

Haemophilus influenzae, although less common, is the more aggressive agent, more frequently resulting in complications, especially meningitis.

Acute mastoiditis causes:

• Streptococcus pneumoniae: most common ⁷
• Haemophilus influenzae: common and more aggressive than pneumococcus
• Aspergillus: aggressive; seen in older patients; frequently associated with facial nerve dysfunction
• Tuberculous otomastoiditis: increasing frequency due to greater immunocompromised population

Acute mastoiditis complications:

• Subperiosteal abscess (mastoid)
• Bezold abscess
• Labyrinthitis
• Petrous apicitis: extension of infection into a pneumatized petrous apex; ~30% of the population has pneumatised petrous apex ⁸
• Intracranial extension
  • Meningitis
  • Subdural empyema
  • Cerebral abscess
  • Dural sinus occlusive disease (DSOD)
• Facial nerve dysfunction
• Thrombosis of mastoid emissary vein (“Griesinger’s sign”)

Currently, the most common complications of acute mastoiditis are sigmoid sinus thrombosis and perisinus empyema ⁹. These complications can be recognized in their early stages by sensitive imaging studies, and properly managed medically and/or surgically.

Chronic mastoiditis

Chronic mastoiditis is a consequence of acute mastoiditis which requires surgical treatment. Chronic mastoiditis presents in a subtle or subclinical fashion after an episode of acute otitis media. Recurrent bouts of otalgia and retro- aural pain, recurrent headaches and febrile episodes. Tympanic membrane may appear infected or postero-superior retraction or perforation with pus. May be no external evidence of peri mastoid inflammation.

Mastoiditis causes

The mastoid bone has a honeycomb-like structure that contains air spaces called mastoid cells. Mastoiditis can develop if the mastoid cells become infected or inflamed, often following a persistent middle ear infection (otitis media).

Cholesteatoma can also cause mastoiditis. This is an abnormal collection of skin cells inside the ear which may prevent the ear draining properly, leading to infection.

Mastoiditis symptoms

The symptoms of mastoiditis typically include:

• redness, tenderness and pain behind the ear
• swelling behind the ear that can cause it to stick out or feel as if it is filled with fluid
• discharge from the ear
• a high temperature, irritability and tiredness
• headache
• hearing loss in the affected ear
• ear pain or discomfort
• redness of the ear or behind the ear

Mastoiditis complications

Although most people with mastoiditis don’t experience serious complications, treatment isn’t always easy and the infection may come back.

If the mastoid bone is severely infected and isn’t removed, it can cause hearing loss and life-threatening health complications such as:

• A blood clot
• Meningitis
• Brain abscess ¹⁰
• Destruction of the mastoid bone
• Dizziness or vertigo
• Epidural abscess
• Facial paralysis
• Partial or complete hearing loss
• Spread of infection to the brain or throughout the body

Mastoiditis diagnosis

Your doctor will examine the inside of your ear with an otoscope (a device with a light and magnifying glass). If your doctor thinks you have mastoiditis as a complication of a middle ear infection, they’ll refer you to an ear, nose and throat (ENT) specialist for further examination and tests.

This usually includes a blood test and an ear culture (where discharge from the ear is tested for a bacterial infection).

Some children may need to have a CT scan (CT scan of the ear and head CT scan), which uses X-rays and a computer to create detailed images of the inside of the skull.

Mastoiditis treatment

Mastoiditis is a serious infection and should be diagnosed and treated quickly with antibiotics.

You may need to go to hospital so antibiotics can be given directly into a vein through a drip.

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.

If you’re admitted to hospital for treatment you’ll need to stay in for a few days until the ENT specialists can be sure the infection is under control.

After surgery

If you’ve had surgery for mastoiditis, you’ll probably need to take one or two weeks off work.

Take care not to get the affected ear wet. You should be able to wash your hair after about a week, providing you don’t get water inside your ear.

You should be able to go swimming around four to six weeks after the operation, depending on how well your ear has healed.

Your doctor should be able to give you specific advice after surgery and at any follow-up appointments.

Mastoiditis prognosis

Mastoiditis can be cured. However, it may be hard to treat and may come back.

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