Describe acute mastoiditis with its complications.

Nature and Presentation

• Acute mastoiditis (acute coalescent mastoiditis) is suppuration and breakdown of the bony septa between the mastoid air cells, converting them into a single abscess cavity.
• It is the commonest complication of acute suppurative otitis media.
• Some mucosal inflammation of the mastoid occurs in every acute otitis media.
• Predisposing factors — inadequate or inappropriate antibiotic treatment of ASOM, or treatment that suppresses symptoms without eradicating infection; a virulent organism; a well-pneumatised mastoid; blockage of the aditus, preventing drainage; and malnutrition, immunosuppression, diabetes and young age
• The cardinal feature IS that the patient deteriorates instead OF improving. After an acute otitis media that seemed to be settling, at 2 weeks, there is recurrence of pain and fever with increasing discharge
• Symptoms — persistent or recurrent throbbing pain behind the ear; fever and toxaemia; and profuse discharge that reaccumulates as fast as it is mopped — the "reservoir sign", indicating a continuing source in the mastoid
• Signs, and these are what make the diagnosis:
• Mastoid tenderness, maximal over the mastoid antrum (over the suprameatal triangle), and over the tip and posterior border
• Postauricular swelling with loss of the retroauricular sulcus, pushing the pinna outward, forward and downward — which is the classical description and the most useful single sign

Complications and Management

• The pus tracks along the path of least resistance, and each route has a name:
• Postauricular (subperiosteal) abscess — through the lateral cortex.
• BEZOLD abscess — through the thin medial side of the mastoid tip, deep to sternocleidomastoid, presenting as a tender swelling in the neck with torticollis and NO postauricular swelling — which is why it is missed
• Citelli abscess — toward the digastric triangle or occipital region
• LUC abscess — beneath the temporalis, presenting in the deep external canal
• Zygomatic mastoiditis — through the zygomatic cells, giving swelling in front of and above the ear with periorbital oedema
• Further complications — facial palsy, labyrinthitis, petrositis (gradenigo syndrome: sixth nerve palsy, deep facial pain and otorrhoea), lateral sinus thrombosis, meningitis and brain abscess
• Masked (latent) mastoiditis is the important variant to recognise: partial treatment with antibiotics suppresses the classical signs, so the patient has persistent dull ache, low-grade fever, mild deafness and malaise without the florid picture — while bone destruction continues and an intracranial complication may be the first obvious event