Otitis Externa Quiz

Ear Disorders: Comprehensive Notes

• Anatomy Overview
  • External Ear: Includes the auricle (pinna) and the external auditory canal (EAC).
  • Middle Ear: Contains the tympanic membrane (eardrum), ossicles (malleus, incus, and stapes), and mastoid air cells.
  • Inner Ear: Includes the cochlea (hearing) and the vestibular apparatus (balance).
  • Eustachian Tube: Connects the nasopharynx to the middle ear, aiding pressure equalization.

External Ear Disorders

• Otitis Externa (Swimmer's Ear)
  • Definition: Inflammation/infection of the external auditory canal (EAC).
  • Common Causes: Pseudomonas aeruginosa, Staphylococcus aureus.
  • Clinical Features: Severe ear pain, scanty discharge, canal edema, possible conductive hearing loss.
  • Management: Topical antibiotics, +/- topical steroids, ear wick for deep penetration of medication, systemic antibiotics (if needed), analgesia, and keeping ear dry.
• Furunculosis (Localized Otitis Externa)
  • Definition: Localized infection of a hair follicle in the lateral (cartilaginous) portion of the EAC.
  • Symptoms: Pain, possible localized swelling/abscess.
  • Management: Topical or oral antibiotics, incision, and drainage if abscess forms.
• Otomycosis (Fungal Otitis Externa)
  • Common Organisms: Candida albicans, Aspergillus species.
  • Clinical Features: itching (pruritus), ear blockage, whitish or blackish discharge.
  • Management: Careful suctioning/debridement of fungal debris, topical antifungals, and keeping the canal dry.
• Viral Otitis Externa (Herpes Oticus)
  • Cause: Herpes simplex virus, presenting with small vesicles in the EAC.

Malignant (Necrotizing) Otitis Externa

- Definition: Aggressive infection extending from the EAC to the skull base (osteomyelitis), often in immunocompromised or diabetic patients.
- Most Common Organism: *Pseudomonas aeruginosa*.
- Clinical Features: Severe, persistent otalgia, granulation tissue in the ear canal.
- Management: Prolonged anti-pseudomonal therapy, debridement of granulation tissue, and controlling any underlying immunosuppressive conditions (e.g., diabetes).

Ear Trauma

• Auricular (Pinna) Trauma:
  • Hematoma (subperichondrial): must be drained to prevent necrosis (cauliflower ear).
  • Suture lacerations if needed; ensure no infection.
• External Canal Trauma: Lacerations or bleeding; ensure no TM perforation. Manage with antiseptic measures.
• TM (Eardrum) Rupture: Direct trauma, barotrauma (blast injury), or infection; may present with sudden pain, possible bloody otorrhea, hearing loss, and tinnitus. Most heal spontaneously.

Middle Ear Disorders

• Acute Otitis Media (AOM)

  • Definition: Acute inflammation of the middle ear, common in children.
  • Pathogens: Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis.
  • Clinical Features: Ear pain, fever, irritability, red, bulging tympanic membrane (TM), possible decreased TM mobility, possible TM perforation, and purulent discharge.
  • Management: Systemic antibiotics (e.g., amoxicillin-clavulanate), analgesics, and antipyretics, observation sometimes in mild pediatric cases.

• Chronic Suppurative Otitis Media (CSOM)

  • Definition: Chronic perforation of the TM with persistent or recurrent ear discharge.
  • Subtypes: Safe (tubotympanic); Unsafe (atticoantral).
  • Clinical Features: Otorrhea (often foul-smelling), conductive hearing loss.
  • Management: Aural toilet (suctioning, cleaning), topical antibiotics (e.g., quinolones), water precautions, and possibly surgery.

• Otitis Media with Effusion (OME) / Serous Otitis Media / “Glue Ear”

  • Definition: Fluid in the middle ear without acute signs of infection.
  • Causes: Eustachian tube dysfunction (e.g., adenoid hypertrophy, allergy).
  • Symptoms: Hearing loss, fullness, no significant pain.
  • Management: Address underlying cause, observe if mild, many resolve spontaneously.

• Cholesteatoma:

  • Definition: Keratinizing squamous epithelium that can erode surrounding structures.
  • Pathogenesis: Retraction pockets, TM perforation, squamous epithelium migration.
  • Clinical Features: Foul-smelling otorrhea, conductive hearing loss, can erode ossicles, facial nerve, semicircular canal.
  • Management: Surgical removal (mastoidectomy), reconstruction (tympanoplasty) may follow.

• Mastoiditis: Infection spreads to mastoid air cells; presents with postauricular pain, swelling.

• Barotrauma (Aerotitis)

  • Definition: Middle ear injury due to pressure changes (flying, diving).
  • Clinical Features: Ear pain, TM retraction, possible fluid or hemorrhage behind TM.
  • Management: Avoiding rapid pressure changes (e.g., chewing gum), Decongestants, nasal steroids to help Eustachian tube function.

General Clinical Presentations

• Otorrhoea (Ear Discharge): Can arise from external or middle ear pathology.
• Otalgia (Ear Pain): Primary from external or middle ear pathology or referred pain (e.g., throat, TMJ).
• Hearing Loss: Can be conductive (external/middle ear lesions) or sensorineural (inner ear lesions).

Vertigo and Imbalance

• Definition: False sense of movement/spinning.
• Causes: Peripheral (inner ear/vestibular) or central (brainstem/cerebellar lesions).
• Common causes of peripheral vertigo: Benign paroxysmal positional vertigo (BPPV), Meniere's disease, labyrinthitis, and vestibular neuritis/labyrinthitis.

High-Yield Considerations

• Otitis Externa: Severe pain, edema, Pseudomonas. Topical drops are mainstay.
• Malignant Otitis Externa: Elderly/diabetic, severe nocturnal pain. Urgent anti-pseudomonal treatment.
• Acute Otitis Media: Common in children; ear pain, fever, red TM. Treat with antibiotics and analgesics.
• Chronic Suppurative OM: Persistent discharge. Watch for cholesteatoma.
• Cholesteatoma: Aggressive epithelium, foul discharge, needs surgery.
• Conductive/Sensorineural HL: Differentiate using tuning forks & audiometry.
• Complications: Mastoiditis, labyrinthitis, petrositis, suspect intracranial spread with persistent fever/neurological deficits.