Acute Otitis Media - Causes, Symptoms and Treatment

🧠 Acute Otitis Media (AOM): Causes, Stages, Symptoms, Treatment

🌬 What is Acute Otitis Media?

Acute Otitis Media (AOM) is an acute inflammation of the middle ear cleft that is of rapid onset and infective origin.

What are the structures in Middle Ear Cleft?

✨ Types of Acute Otitis Media (Based on Occurrence)

• Sporadic: Infrequent, isolated events, often with a URTI.

• Resistant: Symptoms/signs persist beyond 3-5 days of antibiotic treatment.

• Persistent: Persistence or recurrence of symptoms/signs within 6 days of finishing a course of antibiotics.

• Recurrent: Three or more episodes within 6 months OR at least 4-6 episodes within 12 months.

🌍 Epidemiology of Acute Otitis Media

• Most common in infants and young children.
• Incidence decreases with age.

Which age group has the highest incidence of Acute Otitis Media?

🦠 Causes of Acute Otitis Media

AOM typically follows a viral infection of the upper respiratory tract, which then predisposes the middle ear to bacterial invasion.

• Viruses (Primary Trigger)

  • Respiratory Syncytial Virus (RSV)
  • Influenza A
  • Parainfluenza
  • Rhinovirus
  • Adenovirus.

What is the most common virus causing Acute Otitis Media?

What is the pathogenesis of a viral infection leading to Acute Otitis Media?

• Bacteria (Secondary Invaders):

  • Streptococcus pneumoniae
  • Haemophilus influenzae
  • Moraxella catarrhalis
  • Streptococcus pyogenes
  • Staphylococcus aureus
  • Pseudomonas aeruginosa.

What is the most common bacterial cause of Acute Otitis Media?

What is the most common cause of Recurrent or Persistent AOM?

What are the syndromes more commonly associated with Acute Otitis Media?

🚶 Routes of Infection of Acute Otitis Media

• Eustachian Tube: Infection travels via the lumen or subepithelial lymphatics from the nasopharynx to the middle ear.

Why are infants/young children more prone to Acute Otitis Media?

• External Auditory Canal (EAC): Pathogens enter through a TM perforation or ventilation tube (often associated with water exposure).

• Hematogenous (Blood-borne): Very uncommon route.

Which is the most common route of spread of infection in Acute Otitis Media?

Risk Factors of Acute Otitis Media

• Recurrent URTIs and common cold
• Exanthematous fevers
• Recurrent Tonsillitis, Adenoiditis
• Chronic Rhinitis, Sinusitis
• Nasal Allergy
• Nasopharyngeal tumors
• Cleft palate, Palatal palsy
• Barotrauma
• Immunodeficiency (e.g., low IgG2 levels)
• Poor socioeconomic status

🦠 Pathology and Stages of Acute Otitis Media

AOM typically progresses through five stages:

1- Stage of Tubal Occlusion:

• ET blocked (edema/hyperemia post-URTI).
• Middle ear air absorbed → Negative intratympanic pressure → TM retraction, mild middle ear effusion.

2- Stage of Pre-Suppuration:

• Pyogenic organisms invade middle ear cavity (ME).
• Mucosal hyperemia, serous/seromucous inflammatory exudate forms.

What is the appearance of Tympanic membrane described as in Stage of Presuppuration?

3- Stage of Suppuration:

• Pus formation in ME and mastoid air cells.
• TM bulges due to increasing pressure.

4- Stage of Resolution:

• TM ruptures (or resolves with treatment before rupture). Pus/discharge drains.
• Inflammation subsides, symptoms resolve.

What is Lighthouse sign?

5- Stage of Complication:

• Resolution fails (high organism virulence, poor host resistance).
• Infection spreads beyond middle ear confines.
• Leads to various extracranial or intracranial complications.

What are the symptoms and signs seen in the different stages of Acute Otitis Media?

📋 Clinical Features of Acute Otitis Media

• Symptoms

  • Rapid onset otalgia
  • Conductive Hearing Loss
  • Otorrhea (mucopurulent, blood-stained)
  • Fever
  • Crying, irritability, coryzal symptoms (preceding), vomiting, poor feeding
  • Otalgia

• Signs

  • Congested/red Tympanic Membrane
  • Bulging Tympanic Membrane
  • Tympanic Membrane perforation
  • Lighthouse sign

Which quadrant does Tympanic Membrane perforations most commoly occur in Acute Otitis Media?

🩺 Diagnosis of Acute Otitis Media

• Primarily Clinical
• Based on history (rapid onset pain, fever, often preceded by URTI) and otoscopic signs (Tympanic Membrane appearance: congestion, bulging, or perforation with discharge).
• History of crescendo otalgia followed by relief with discharge is highly suggestive.

🩺 Investigations of Acute Otitis Media

• Usually NOT needed for routine AOM.

• Audiological Tests: Show Conductive Hearing Loss

• CT Temporal Bone: Only indicated for suspicion of refractory mastoiditis or other complications. Shows clouding, possible demineralization of air cell septa (coalescent mastoiditis).

• Bacteriological Examination: Culture and Sensitivity of ear discharge. Done for severe/resistant/recurrent cases or if specific organism suspicion.

💊 Treatment of Acute Otitis Media

Management depends on severity and stage, ranging from conservative to surgical.

• Conservative Treatment: For mild cases.

1- Analgesics & Antipyretics: Paracetamol, Ibuprofen (very effective for pain/fever).

2- Antibiotics: Mainstay if symptoms worsen or persist after 3-4 days, or for specific indications.

What are the Inidcations of antibiotics in Acute Otitis Media?

Drug of Choice: Amoxicillin (80-90 mg/kg/day in divided doses) for 5-10 days (often 5-7 days is sufficient).

What is the Drug of Choice in Drug-resistant Pneumococcus?

What is the Drug of Choice in Persistent/Resistant AOM?

3- Decongestants:

• Nasal Decongestant Drops: (Ephedrine, Oxymetazoline, Xylometazoline) To reduce ET edema, promote ventilation.
• Oral Decongestants (Pseudoephedrine)

4- Aural Toileting: Suctioning/cleaning discharge from EAC if present.\

• Myringotomy: Surgical incision of the TM to drain pus/effusion.

What are the Indications of Myringotomy in Acute Otitis Media?

🏥 Management of Recurrent Acute Otitis Media

• Risk Factor Reduction: Reduce exposure to daycare children, feed semi upright, restrict pacifier use, avoid passive smoke.

• Antibiotic Prophylaxis: Single daily dose of Amoxicillin (20 mg/kg) for 3-6 months (consider risks vs benefits).

• Xylitol: Sweetener inhibiting bacterial growth/attachment in nasopharynx (chewing gum, syrup).

• Zinc: Micronutrient for immune function.

• Vaccination: Influenza vaccine (viruses), Pneumococcal Conjugate Vaccine (PCV) (bacteria).

• Surgical Prophylaxis: Tympanostomy Tube (Grommet) insertion for ventilation in recurrent/chronic cases.

🏥 Outcomes of Acute Otitis Media

• Rapid resolution (with or without antibiotics).
• Resistance to antibiotics.
• Persistence or recurrence shortly after antibiotics.
• Subsequent recurrence.
• Progression to Otitis Media with Effusion (OME) and CHL.
• TM perforation.
• Development of Complications.

💊 Complications of Acute Otitis Media

• Most common: TM Perforation (1-10%).

• Extracranial: Acute Mastoiditis, Petrositis, Facial Nerve Palsy, Labyrinthitis, Subperiosteal Abscess, Sigmoid Sinus Thrombosis (can be extra/intracranial).

• Intracranial: Meningitis, Extradural Abscess, Subdural Empyema, Focal Otitic Encephalitis, Brain Abscess, Otitic Hydrocephalus.

• Acute Necrotizing Otitis Media: A severe variant seen in children with Measles, Scarlet Fever, Influenza (causes more extensive TM/ossicular necrosis).

What is the Differential Diagnosis of Acute Otitis Media?

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