Chronic Otitis Media (COM) & Cholesteatoma
1) Definition & Core Concept
Chronic Otitis Media (COM)
- การติดเชื้อ/อักเสบของ middle ear ± mastoid ร่วมกับ
👉 Tympanic membrane (TM) perforation แบบเรื้อรัง - อาการหลัก:
otorrhea, hearing loss, aural fullness, บางรายมี otalgia หรือ vertigo
Cholesteatoma
- ก้อน keratinized squamous epithelium ใน
middle ear/mastoid
- ไม่ใช่ tumor จริง แต่เป็น locally
destructive lesion →
ทำลาย ossicle, bone, intracranial spread ได้
2) Classification (High-yield clinical categories)
2.1 Chronic Otitis Media
|
Type |
ลักษณะ |
|
Inactive (benign COM) |
TM perforation + ไม่มี
otorrhea |
|
Active COM |
TM perforation + มี
otorrhea |
|
CSOM (Chronic suppurative OM) |
Persistent purulent otorrhea ผ่าน TM perforation |
|
COME |
Intact TM + sterile effusion ≥3
เดือน |
WHO: CSOM = otorrhea ≥2 สัปดาห์ (แต่ ENT
มักใช้ ≥6 สัปดาห์–3 เดือน)
3) Microbiology (CSOM – Clinically important)
Most common pathogens
- Pseudomonas
aeruginosa (สำคัญที่สุด)
- Staphylococcus
aureus (รวม MRSA)
Others
- Proteus,
Klebsiella, E. coli (GNB)
- Anaerobes
(8–59%)
- Rare:
- Mycobacterium
tuberculosis (ต้องนึกใน TB endemic area เช่น Southeast Asia)
- Fungi:
Aspergillus, Candida
Clinical pearl:
Biofilm formation →
chronic, refractory infection
4) Pathogenesis (Stepwise mechanism)
4.1 Chronic OM
1.
Recurrent AOM/ET dysfunction
2.
Chronic negative middle ear pressure
3.
TM retraction ± rupture
4.
Chronic perforation → persistent infection
5.
Pathogens enter via:
o Eustachian
tube (nasopharynx)
o External
canal (ผ่าน perforated TM)
4.2 Cholesteatoma formation
Primary acquired
- ET
dysfunction → TM
retraction pocket (pars flaccida)
- Keratin
debris accumulation →
expanding cholesteatoma
Secondary acquired
- Squamous
epithelium migration ผ่าน TM perforation
Mechanism of bone destruction
- Collagenase
/ protease
- Osteoclastic
bone resorption
- Chronic
infection + inflammation
5) Clinical Features (Exam-relevant)
5.1 Chronic Otitis Media
Classic presentation
- Chronic
or recurrent foul-smelling otorrhea
- Conductive
hearing loss
- Usually
painless
- Worse
with water exposure
Physical exam
- TM
perforation + otorrhea
- Inflamed
middle ear mucosa (CSOM)
5.2 Cholesteatoma (Key red-flag entity)
Symptoms
- Progressive
hearing loss
- Persistent
otorrhea
- Vertigo
(late)
- Facial
weakness (advanced)
Otoscopic findings (high yield)
- Retraction
pocket (pars flaccida > pars tensa)
- Squamous
debris / crust
- “Pearly
white mass” behind TM
- Granulation
tissue
- Attic
lesion (posterosuperior quadrant)
Clinical pearl:
Attic retraction + debris = cholesteatoma until proven
otherwise
6) Diagnosis & Evaluation (Stepwise clinical
approach)
6.1 Clinical diagnosis (Primary care/ER)
Active COM:
- Chronic
otorrhea
- Perforated
TM
- Minimal
systemic symptoms
Inactive COM:
- Dry
TM perforation (incidental finding)
6.2 ENT referral indications (Diagnostic evaluation)
ควร refer ENT ใน:
- Active
COM
- Suspected
cholesteatoma
- Unclear
diagnosis
- Cranial
neuropathy / vertigo / CNS signs (urgent)
6.3 Microbiologic evaluation (CSOM)
- Obtain
culture in ALL CSOM
- Send:
- Gram
stain
- Aerobic
+ anaerobic culture
- Method:
❗ Aspiration via otomicroscopy (not ear swab → contamination)
Consider special cultures if:
- TB
suspicion (pale TM, multiple perforations, profound HL)
- Fungal
features (itching, refractory)
6.4 Audiometry
Indications:
- All
cholesteatoma
- Hearing
loss
- Persistent
otorrhea
Purpose:
- Type:
conductive vs SNHL
- Severity
baseline
- Surgical
planning
6.5 Imaging (Very high-yield)
CT Temporal Bone (non-contrast)
Indications:
- ALL
cholesteatoma
- Suspected
bone erosion
- Surgical
planning
Findings:
- Ossicular
erosion
- Scutum
erosion
- Mastoid
involvement
- Fistula
formation
MRI (with contrast)
Indications:
- Suspected
intracranial complication
- Labyrinthine
involvement
- Recurrence
monitoring
6.6 Biopsy indications
- Persistent
granulation tissue
- Pain
(atypical for COM)
- No
response after 2–4 weeks treatment
→ Rule out malignancy / granulomatous disease
7) Differential Diagnosis (Key distinctions)
- Otitis
externa (painful canal, normal TM)
- Granulomatosis
with polyangiitis
- Nasopharyngeal
carcinoma
- Langerhans
cell histiocytosis
- TB
otitis media
Red flag for malignancy:
- Persistent
otorrhea + pain + treatment failure
8) Management (Clinical Practice Guideline Style)
8.1 General measures (ALL COM)
Water precautions (critical)
- No
swimming/submerging
- Petroleum
jelly cotton while bathing
- Ear
plugs recommended
Aural toilet
- Suction
cleaning by ENT
- ❗
Avoid self-irrigation (risk ototoxicity + worsening infection)
8.2 Inactive COM
- No
specific treatment if asymptomatic
- Water
precautions only
- Follow-up
8.3 Active COM / CSOM (Key Treatment Strategy)
First-line: Topical antibiotics (preferred)
Recommended agents (safe in TM perforation)
- Ofloxacin
otic
- Ciprofloxacin
± dexamethasone
Duration: - 2
weeks (extend to 4 weeks if persistent infection)
Rationale:
- Higher
local concentration
- Better
penetration than systemic antibiotics
- Less
systemic resistance
⚠️ Avoid:
- Aminoglycoside
ear drops (ototoxic in perforated TM)
8.4 Systemic antibiotics (Indications)
- Failure
of topical therapy
- Complicated
infection
- Systemic
symptoms (fever, leukocytosis)
- Invasive
infection
- Resistant
organisms
Empiric coverage should include:
- Pseudomonas
- MRSA
- Anaerobes
Example severe regimens:
- Vancomycin
+ Cefepime/Ceftazidime + Metronidazole
(avoid vanc + piperacillin-tazobactam → nephrotoxicity)
9) Cholesteatoma Management (Critical Concept)
Definitive treatment = SURGERY
Indication:
- ALL
cholesteatomas (no medical cure)
Goals:
- Eradicate
disease
- Create
dry ear
- Prevent
complications
- Restore
hearing (if possible)
10) Surgical options (ENT)
- Tympanoplasty
(TM repair ± ossicular reconstruction)
- Tympanomastoidectomy
- Mastoidectomy
(canal wall intact vs canal wall down)
- Ossicular
chain reconstruction
Clinical pearl:
Long process of incus = most vulnerable to erosion
11) Complications (High-yield & life-threatening)
11.1 Extracranial
- Mastoiditis
- Facial
nerve palsy
- Labyrinthitis
11.2 Intracranial (0.1–2%)
- Meningitis
- Brain
abscess (temporal/cerebellar)
- Lateral
sinus thrombosis
- Intracranial
abscess
Red flags:
- Persistent
headache
- Seizures
- Fever
+ otorrhea
- Focal
neurologic deficit
- Severe
ear pain (atypical for COM)
12) Mastoiditis in COM (Emergency pearls)
Symptoms:
- Postauricular
swelling
- Fever
- Displaced
auricle
- Mastoid
tenderness
Management:
- Admit
- IV
antibiotics (cover MRSA + Pseudomonas)
- CT
temporal bone
- ENT
surgical consult ± mastoidectomy
13) Key Clinical Pearls (Exam & Practice)
- Chronic
otorrhea + TM perforation = COM until proven otherwise
- Foul-smelling
discharge → think
CSOM/Pseudomonas
- Painless
chronic discharge = classic COM
- Pain
+ treatment failure →
rule out malignancy
- Retraction
pocket + debris = cholesteatoma
- Topical
fluoroquinolone = first-line CSOM
- Cholesteatoma
= surgical disease (not antibiotic disease)
14) Quick Comparison (AOM vs COM vs Cholesteatoma)
|
Feature |
AOM |
COM |
Cholesteatoma |
|
Pain |
+++ |
Minimal |
Variable |
|
Fever |
Possible |
Rare |
Rare |
|
TM |
Bulging |
Perforated |
Retraction pocket/mass |
|
Otorrhea |
Acute |
Chronic |
Persistent |
|
Treatment |
Systemic antibiotics |
Topical antibiotics |
Surgery |
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