Describe masked mastoiditis and recurrent acute otitis media.

Acute Mastoiditis in the Antibiotic Era

• Masked (latent, subacute) mastoiditis is continuing coalescent infection of the mastoid in which antibiotic treatment has suppressed the classical signs without eradicating the disease.
• Bone destruction proceeds silently, and a complication may be the first obvious event.
• It arises when acute otitis media is treated with an antibiotic that is inadequate in dose, duration, spectrum or penetration — enough to suppress symptoms, not enough to sterilise the mastoid. It is therefore a disease created by treatment, and is commoner where antibiotics are freely available without supervision, as in much of India

Recurrent Acute Otitis Media and Prevention

• Recurrent acute otitis media is conventionally defined as 3 or more episodes in 6 months, or 4 or more in 12 months, with complete resolution between
• Risk factors, divided into those that can and cannot be changed:
• Unmodifiable — young age (the infant Eustachian tube); male sex; a family history; craniofacial anomalies — cleft palate and down syndrome; immunodeficiency; and primary ciliary dyskinesia
• Modifiable, and these are what should be addressed at the consultation — passive smoking; bottle-feeding, especially lying flat, and lack of breastfeeding; prolonged pacifier (dummy) use; day-care attendance and crowding; untreated allergic rhinitis and adenoid disease; and malnutrition and anaemia
• Assessment — confirm the diagnosis of the episodes (many are over-diagnosed); check the ear is normal between episodes, since persistent effusion means a different problem; examine the nose, adenoid and palate; test the hearing; and consider immunological assessment where episodes are severe, frequent or accompanied by infections elsewhere
• Prevention:
• Address the modifiable factors first — stopping household smoking, breastfeeding, upright feeding and discontinuing the dummy after 6 months. These cost nothing and are consistently omitted in favour of prescriptions
• Vaccination — pneumococcal conjugate vaccine and annual influenza vaccine, both of which have measurably reduced incidence
• Treat allergic rhinitis and sinusitis
• Antibiotic prophylaxis (long-term low-dose amoxicillin) reduces episodes only modestly and promotes resistance, and is now rarely recommended — a change from older teaching worth stating explicitly
• Grommet insertion is the surgical option of choice, reducing the frequency of episodes and allowing any that occur to be treated with topical rather than systemic antibiotics
• Adenoidectomy, particularly with nasal obstruction or at a second set of grommets
• Follow up until the ear and hearing are normal between episodes, since unrecognised persistent effusion is the commonest reason recurrence appears to continue