What is the difference between Csom and Asom in medical treatment?

CSOM vs ASOM: Key Differences in Medical Treatment

CSOM (Chronic Suppurative Otitis Media) and ASOM (Acute Suppurative Otitis Media/Acute Otitis Media) differ fundamentally in duration, pathophysiology, and treatment approach—ASOM represents acute infection requiring short-term antibiotic therapy, while CSOM involves persistent tympanic membrane perforation with chronic drainage requiring topical quinolones and potential surgical intervention.

Defining Characteristics

ASOM (Acute Otitis Media)

• Acute onset with signs and symptoms of middle ear infection including ear pain, fever, and bulging tympanic membrane 1
• Typically resolves within days to weeks with appropriate treatment 1
• May present with tympanic membrane rupture and acute drainage 2
• Most common bacterial pathogens: Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis 2, 3

CSOM (Chronic Suppurative Otitis Media)

• Persistent tympanic membrane perforation with chronic ear discharge lasting weeks to months 1
• Accounts for 31 million cases worldwide annually with 21,000 deaths from complications 1
• Associated with significant hearing loss (global prevalence of 31 per 10,000) 1
• Causes substantially lower health-related quality of life across multiple parameters 1

Diagnostic Approach

ASOM Diagnosis

• Pneumatic otoscopy showing bulging tympanic membrane with impaired mobility (94% sensitivity, 80% specificity) 1
• Tympanometry as adjunct when diagnosis uncertain 1
• Algorithm using bulging and opacification correctly classifies 99% of ears 1
• Active drainage through perforation if tympanic membrane ruptures 2

CSOM Diagnosis

• Otoscopy or otomicroscopy revealing tympanic membrane perforation 1
• May require suctioning of ear discharge for adequate visualization 1
• Assessment of perforation size and location guides management 4
• Audiometry correlates with hearing function impairment 1

Treatment Differences

ASOM Treatment Strategy

First-Line Antibiotic Selection:

• High-dose amoxicillin-clavulanate (90 mg/kg/day of amoxicillin with 6.4 mg/kg/day of clavulanate in 14:1 ratio, divided twice daily) for ruptured tympanic membrane 2
• Standard amoxicillin (80-90 mg/kg/day) for intact tympanic membrane 5
• Coverage for β-lactamase-producing organisms becomes critical with perforation 2

Alternative Options:

• Cefdinir (14 mg/kg/day) or cefpodoxime (10 mg/kg/day) for non-severe penicillin allergy 2, 5
• Azithromycin (10 mg/kg day 1, then 5 mg/kg days 2-5) has lower efficacy against S. pneumoniae 2, 6
• Ceftriaxone IM indicated for acute bacterial otitis media caused by susceptible organisms 3

Duration:

• 10-day course for ruptured tympanic membrane to ensure complete pathogen eradication 2
• 5-7 days may be adequate for adolescents with intact membrane 5
• Shorter courses risk treatment failure with compromised tympanic membrane 2

Adjunctive Measures:

• Immediate pain control with acetaminophen or ibuprofen regardless of antibiotic use 5
• Topical antibiotic drops as adjunct (not replacement) when active drainage present 2
• Keep ear dry during healing to prevent contamination through perforation 2, 4

CSOM Treatment Strategy

Topical Antibiotic Therapy:

• Topical quinolones more effective than no treatment, topical antiseptics, or systemic antibiotics for clearing aural discharge (<4 weeks) 1
• Quinolones have advantage of being non-ototoxic compared to aminoglycosides 1
• Must use only non-ototoxic medications to avoid middle ear structure damage 4
• Compressed cellulose wick facilitates drug delivery with significant canal edema 4

Systemic Antibiotics:

• Limited evidence suggests systemic plus topical antibiotics not more effective than topical alone 1
• Reserve systemic antibiotics for infection extension beyond ear canal or specific host factors (diabetes, immunocompromised) 4

Surgical Considerations:

• Temporalis fascia tympanoplasty versus cartilage tympanoplasty for perforation repair 1
• Cartilage grafts show fewer postoperative perforations but no hearing differences 1

Critical Precautions:

• Never irrigate the ear canal with perforation present—risks middle ear infection, vertigo, or ototoxicity 4
• Avoid alcohol-containing drops or ototoxic preparations that can enter middle ear 4
• Avoid cotton-tipped applicators causing further trauma 4

Immunological Differences

Serum and Middle Ear Immunoglobulin Patterns:

• ASOM shows mean serum IgG 666.1 mg/dl with MES IgG 203.4 mg/dl 7
• CSOM demonstrates elevated mean serum IgG 1,321.1 mg/dl with MES IgG 511.5 mg/dl 7
• Monitoring serum and MES IgG in ASOM provides useful index for assessing progression to chronicity 7
• MES:serum ratios for IgG range 0.1-0.4 in both conditions 7

Follow-Up Requirements

ASOM Follow-Up

• Reassess at 48-72 hours if symptoms persist or worsen 2, 5
• Confirm tympanic membrane perforation healing after antibiotic completion 2
• Consider second-line agent (amoxicillin-clavulanate) if treatment failure 5

CSOM Follow-Up

• Reassess within 48-72 hours if no response to initial therapy 4
• Long-term monitoring for hearing loss and quality of life impact 1
• Surgical referral consideration for persistent perforation 1

Common Pitfalls to Avoid

In ASOM Management:

• Underestimating need for broader coverage when tympanic membrane ruptured—standard amoxicillin insufficient due to β-lactamase-producing organisms 2
• Inadequate treatment duration with perforation leads to treatment failure and prolonged healing 2
• Overreliance on topical therapy alone without systemic antibiotics for active infection 2

In CSOM Management:

• Using ototoxic preparations that damage middle ear structures through perforation 4
• Irrigating ear canal causing middle ear infection or vertigo 4
• Failing to distinguish surface tympanic membrane findings from middle ear pathology 1
• Delayed surgical referral for persistent perforation affecting quality of life 1