Mastoiditis
Acute mastoiditis is a suppurative infection of the mastoid air cells, almost always arising as an extension of untreated or inadequately treated acute otitis media. It is diagnosed clinically by postauricular erythema, tenderness, and swelling with the auricle displaced anteriorly, and is treated with intravenous antibiotics escalating to myringotomy or mastoidectomy when abscess or complications are present.
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What this article covers
- Overview
Suppurative infection of the mastoid air cells: mastoiditis is inflammation and infection extending from the middle ear into the mastoid antrum and air-cell system, almost always a complication of…
- Epidemiology
A complication of a very common childhood infection: acute otitis media is one of the most common infections of children, and mastoiditis is one of its recognized suppurative complications.
- Risk factors
Untreated or inadequately treated acute otitis media: the dominant risk factor; recent antibiotic use, resistant organisms, or recurrence within 1 month of a prior episode increases the chance of an…
- Pathophysiology
Infection tracks from the middle ear into the mastoid antrum: the same pathogens responsible for acute otitis media (Streptococcus pneumoniae, nontypeable Haemophilus influenzae, Moraxella…
- Clinical features
Postauricular erythema, tenderness, and swelling with the auricle displaced anteriorly: the classic sign of acute mastoiditis, reflecting a subperiosteal collection pushing the ear outward and…
- Differential diagnosis
Acute otitis media without mastoid extension: bulging erythematous tympanic membrane and otalgia but no postauricular erythema, tenderness, swelling, or auricular displacement.
- Diagnosis
Mastoiditis is a clinical diagnosis: postauricular erythema, tenderness, and swelling with anterior displacement of the auricle, fever, and otalgia in a patient with current or recent acute otitis…
- Management
Start empiric intravenous antibiotics covering the acute otitis media pathogens plus Staphylococcus aureus: give ampicillin-sulbactam 3 g IV every 6 hours (50 mg/kg IV every 6 hours in children, ampicillin component) as first-line therapy.
- Complications
Intracranial extension: epidural abscess, subdural abscess, meningitis, or brain abscess are the most serious complications, presenting with severe headache, vomiting, seizures, or a focal neurologic…
- Prognosis
Good with prompt antibiotics and, when needed, surgical drainage: most patients improve once IV antibiotics are started and any abscess or coalescent disease is surgically addressed.
- Prevention
Treat acute otitis media according to guidance rather than under-treating it: use high-dose amoxicillin (80 to 90 mg/kg/day) for 10 days as first-line therapy in children, and switch to…
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Related articles
- Acute otitis media
Acute otitis media is a suppurative middle ear infection, mostly in young children, diagnosed by otoscopy showing a bulging, erythematous tympanic membrane with an effusion, and it is treated with observation or amoxicillin depending on age and severity.
- Cholesteatoma
Cholesteatoma is an abnormal growth of keratinizing squamous epithelium in the middle ear that erodes the ossicles, mastoid, and adjacent skull base; it is confirmed on otoscopy, staged by CT, and requires mastoidectomy with tympanoplasty because no medical therapy is curative.
- Chronic suppurative otitis media
Chronic suppurative otitis media is continuous otorrhea through a perforated tympanic membrane for more than six weeks without systemic symptoms. Management starts with topical fluoroquinolone ear drops and aural toilet, escalating to systemic antibiotics or tympanoplasty for refractory disease or cholesteatoma.
- Otitis media with effusion
Otitis media with effusion is middle-ear fluid persisting without signs of acute infection, most often in young children after an upper respiratory infection or acute otitis media, managed mainly with observation and reserving tympanostomy tubes for persistent hearing loss.
- Otitis externa
Otitis externa is diffuse inflammation of the external auditory canal, usually bacterial (Pseudomonas or Staphylococcus aureus) and diagnosed clinically by tragal tenderness and canal erythema with otorrhea. Uncomplicated disease is treated with topical antibiotic-steroid otic drops for 7 days, while malignant (necrotizing) otitis externa in a diabetic or immunocompromised patient is skull-base osteomyelitis requiring systemic antipseudomonal therapy and urgent otolaryngology referral.
- Necrotizing (malignant) otitis externa
Necrotizing (malignant) otitis externa is skull-base osteomyelitis, almost always from Pseudomonas aeruginosa, that spreads from otitis externa into the temporal bone of older diabetics and other immunocompromised patients. Otalgia out of proportion to exam plus granulation tissue at the bony-cartilaginous junction of the canal is the hallmark, and treatment is weeks of antipseudomonal therapy, not a course of ear drops.
- Brain abscess
Brain abscess is a focal, ring-enhancing suppurative infection of the brain parenchyma most often from contiguous sinus, ear, or dental spread or hematogenous seeding, diagnosed by contrast MRI and image-guided aspiration and treated with predisposing-source-directed empiric antibiotics plus drainage of abscesses larger than 2.5 cm.
- Bacterial meningitis (age over 1 month)
Acute purulent infection of the meninges beyond the neonatal period, most often from Streptococcus pneumoniae or Neisseria meningitidis, diagnosed by CSF analysis after prompt lumbar puncture and treated with immediate empiric intravenous antibiotics plus adjunctive dexamethasone, since any delay in therapy worsens outcome and mortality remains near 25%.