Complications of CSOM

🦻 Complications of Chronic Suppurative Otitis Media (CSOM)

Not every case of CSOM develops complications - they occur in certain individuals due to a combination of host, microbial, and environmental factors.

Understanding why complications occur and how infection spreads is key to both prevention and management.

⚠️ Factors Influencing the Development of Complications

Complications generally occur when infection is uncontrolled or inadequately treated.
The following are predisposing factors:

1️⃣ Age

• Commonly seen in:
  • Children (1st decade)
  • Elderly individuals

2️⃣ Poor Socioeconomic Status

• Associated with:

  • Overcrowding
  • Poor personal hygiene
  • Limited health education
  • Restricted access to healthcare

• These factors together increase the risk of persistent infection → complications.

3️⃣ Virulence and Resistance of Microorganisms

Certain antibiotic-resistant strains make CSOM more difficult to control.

Name some resistant micro organisms associated with CSOM and their mechanism of resistance.

4️⃣ Immunocompromised Host

Patients with low immunity are more prone to develop complications.

Examples include:

• AIDS
• Uncontrolled diabetes mellitus
• Organ transplant patients (on immunosuppressants)
• Cancer patients on chemotherapy

5️⃣ Presence of Preformed Pathways

Infections may spread easily beyond the middle ear if natural or acquired defects exist.

Examples:

• Dehiscence of the bony facial canal or tegmen tympani
• Post-surgical defects (stapedectomy, fenestration)
• Temporal bone fractures
• Perilymph fistula
• Mondini’s abnormality
• Dehiscence in the floor of middle ear over the jugular bulb

These defects act as shortcuts for infection spread → facilitating intracranial or extracranial complications.

6️⃣ Presence of Cholesteatoma

• Cholesteatoma causes osteitis and granulation tissue formation → bone destruction.

• This allows infection to spread into adjacent spaces → leading to serious complications.

🧬 Pathways of Spread of Infection

There are three main routes by which infection spreads beyond the middle ear cleft:

1️⃣ Direct Bone Erosion

• Acute Otitis Media: Spread via hyperemic decalcification

• Chronic Otitis Media: Spread due to osteitis or cholesteatoma erosion

2️⃣ Venous Thrombophlebitis

• Mechanism:

  • Veins in Haversian canals → communicate with dural veins
  • These connect to dural venous sinuses and superficial cerebral veins

• Infection spreads → causes sinus thrombophlebitis and even cortical vein thrombosis.

3️⃣ Preformed Pathways

These are anatomical or pathological defects that facilitate spread:

What is the most common route of Spread of Infection of CSOM?

What is the most common route of Spread of acute infection?

🧩 Classification of Complications of CSOM

Complications of CSOM are broadly divided into:

A. Extracranial Complications

These are further subdivided into:

1️⃣ Intratemporal Complications (within the temporal bone)

• Mastoiditis
• Petrositis
• Facial nerve palsy
• Labyrinthitis

2️⃣ Extratemporal Complications

• Postauricular abscess
• Zygomatic abscess
• Bezold’s abscess
• Luc’s abscess
• Citelli’s abscess
• Parapharyngeal / Retropharyngeal abscess

B. Intracranial Complications

• Extradural abscess
• Subdural abscess
• Meningitis
• Brain abscess
• Sigmoid sinus thrombosis
• Otitic hydrocephalus