chronic otitis media

**Definition and types** - Chronic otitis media is long-standing (generally >3 months) middle ear and mastoid inflammation. Forms: 1. **Chronic suppurative otitis media (CSOM):** a perforated tympanic membrane (TM) with persistent or intermittent purulent drainage for >6 weeks to 3 months. 2. **Chronic otitis media with effusion:** persistent middle ear fluid behind an intact TM, without acute infection signs. 3. **Cholesteatoma:** an accumulation of keratinizing stratified squamous epithelium (keratin debris) in the middle ear or mastoid. It may be congenital (a white mass behind an intact TM in a child with no prior history of infection or perforation) or acquired (from a retraction pocket or perforation). 4. **Adhesive otitis media and tympanosclerosis** (hyalinized collagen/calcific plaques in the TM, "chalky white patches") are other chronic sequelae.

**Pathophysiology** - Eustachian tube dysfunction causes negative middle ear pressure, effusion, and recurrent infection. This is most common in children because the tube is shorter, more horizontal, and floppier. Risk factors include cleft palate, Down syndrome, adenoid hypertrophy, daycare, passive smoke exposure, lack of breastfeeding, and immunodeficiency. - Recurrent acute otitis media leads to TM perforation. Biofilm formation and persistent infection maintain the disease. - Common organisms in acute otitis media are *S. pneumoniae*, nontypeable *H. influenzae*, and *Moraxella catarrhalis*. In CSOM the typical organisms are ***Pseudomonas aeruginosa***, *Staphylococcus aureus*, and anaerobes (Proteus and others also occur).

**Clinical features** - Painless otorrhea, which is often foul-smelling in cholesteatoma. - Conductive hearing loss. Ossicular erosion (especially the long process of the incus) causes this. - Otoscopy: a TM perforation, a retraction pocket, or a white pearly mass (cholesteatoma). Fever and severe pain are usually absent, so their presence suggests a complication.

**Complications** - Intratemporal: mastoiditis, petrositis (Gradenigo syndrome: otorrhea, retro-orbital pain, CN VI palsy), facial nerve paralysis, labyrinthitis or labyrinthine fistula (vertigo), and ossicular destruction. - Intracranial: meningitis, brain or epidural abscess, sigmoid sinus thrombosis, and temporal lobe abscess. - Cholesteatoma erodes bone through local inflammation and osteoclast activation, so it needs surgery.

**Diagnosis** - Clinical, with otoscopy or microscopy. Audiometry shows conductive loss. - Tympanometry shows a flat (type B) curve with a perforation (large ear canal volume) or with effusion. - CT temporal bone is used if cholesteatoma or complications are suspected. Add MRI if intracranial extension is suspected.

**Management** - CSOM: aural toilet and **topical** antibiotics, usually a fluoroquinolone (ciprofloxacin) with or without a steroid. Topical fluoroquinolones are preferred over systemic antibiotics and are safe with a perforation because they are non-ototoxic. Avoid ototoxic aminoglycoside drops with a perforation. Keep the ear dry. - Persistent perforation: tympanoplasty (myringoplasty). - Cholesteatoma: surgical excision (tympanomastoidectomy). Ossicular reconstruction may be needed. - Chronic effusion: observation, then tympanostomy (ear) tubes if it persists for ≥3 months with hearing loss or developmental concerns. Adenoidectomy may help in older children. - Prevention: pneumococcal vaccination, influenza vaccination, and avoiding smoke exposure.

**High-yield board points** - Chronic otitis media with otorrhea and a **white mass behind the TM** is cholesteatoma until proven otherwise. - *Pseudomonas* is the classic CSOM organism. - Chronic infection with conductive hearing loss: think ossicular erosion. - Facial nerve palsy, vertigo, or CNS signs signal a complication. - Distinguish from otitis externa. Otitis externa causes pain on tragal or pinna movement, and *Pseudomonas* also causes malignant (necrotizing) otitis externa in diabetics and the immunocompromised.