Labyrinthitis

🦻 Labyrinthitis

Labyrinthitis is an inflammatory condition of the inner ear that often arises as a complication of CSOM (Chronic Suppurative Otitis Media) or AOM (Acute Otitis Media).

It can be classified into three types:

1. Circumscribed Labyrinthitis (Labyrinthine fistula)
2. Diffuse Serous Labyrinthitis
3. Diffuse Suppurative (Purulent) Labyrinthitis

In this post, we focus on Diffuse Serous and Diffuse Suppurative labyrinthitis.

🔍 Diffuse Serous Labyrinthitis

📖 Definition of Diffuse Serous Labyrinthitis

A diffuse intralabyrinthine inflammation without pus formation.

• Reversible if diagnosed and treated early

📌 Causes of Diffuse Serous Labyrinthitis

• Most common: Pre-existing labyrinthine fistula (CSOM or cholesteatoma)

• Acute otitis media or mastoiditis (bacterial/viral toxins invading via oval/round window)

• Meningeal inflammation

• Ear surgeries

🩺 Clinical Features of Diffuse Serous Labyrinthitis

• Spontaneous vertigo in a patient with middle ear infection → strong suspicion

• Associated nausea & vomiting

• Irritative type nystagmus

• Positive fistula test (if due to labyrinthine fistula)

• Mild, reversible sensorineural hearing loss

• Caloric test: diminished vestibular response

What is Irritative type of nystagmus?

What is fistula test? What does Positive Fistula test mean?

What will happen if Diffuse Serous Labyrinthitis is left untreated?

💊 Treatment of Diffuse Serous Labyrinthitis

Goals: Prevent progression to suppurative stage & avoid meningitis

• Bed rest with head immobilized (affected ear up)

• IV antibiotics – control middle ear & labyrinth infection

• Labyrinthine sedatives for vertigo relief

• Myringotomy ± grommet insertion

• Surgical options:

  • Cortical mastoidectomy (acute mastoiditis)
  • Modified radical mastoidectomy (cholesteatoma)

What are some labyrinthine sedatives used in Diffuse Serous Labyrinthitis?

🧬 Diffuse Suppurative (Purulent) Labyrinthitis

📖 Definition of Diffuse Suppurative Labyrinthitis

A diffuse pyogenic infection of the labyrinth → permanent loss of vestibular & cochlear function.

• Irreversible condition

📌 Causes of Diffuse Suppurative Labyrinthitis

• Often follows serous labyrinthitis when pyogenic organisms enter via:
  • Pathological/surgical fistula (CSOM, cholesteatoma, AOM, meningitis)

What are the Predisposing factors of Diffuse Suppurative Labyrinthitis?

🦠 Routes of Infection of Diffuse Suppurative Labyrinthitis

1. Tympanogenic

2. Meningogenic – Meningitis

3. Hematogenic – Systemic infection, meningitis, encephalitis, brain abscess

What is the most common route of infection of Diffuse Suppurative Labyrinthitis?

🩺 Clinical Features of Diffuse Suppurative Labyrinthitis

1️⃣ Acute Stage (1–2 weeks)

• Rapid onset
• Severe, persistent symptoms (8–12 hrs) not responding to treatment initially
• Head movement triggers severe vertigo
• Irritative nystagmus → later becomes paralytic nystagmus
• Severe SNHL, past pointing, tendency to fall towards diseased side
• Unilateral

2️⃣ Chronic (Latent/Fibrous) Stage (1–6 weeks)

• Milder vestibular upset, positional vertigo
• Absence of cochlear & vestibular functions
• Bilateral cases → difficulty walking in dark/soft surfaces

3️⃣ Healed (Compensated/Ossification) Stage

• Labyrinthitis ossificans

What is Labyrinthitis ossificans?

💊 Treatment of Diffuse Suppurative Labyrinthitis

• Same principles as serous labyrinthitis
• Rarely, labyrinth drainage if it acts as a source of intracranial complication