In the absence of local or regional adenopathy, consider noninfectious causes of inflammation, among which trauma, insect bites, and environmental exposures are more commonly implicated than are autoimmune diseases (e.g., lupus) or vasculitides (e.g., granulomatosis with polyangiitis).
- Auricular cellulitis: Tenderness, erythema, swelling, and warmth of the external ear, particularly the lobule, follow minor trauma. Treat with warm compresses and antibiotics active against S. aureus and streptococci (e.g., cephalexin, dicloxacillin).
- Perichondritis: Infection of the perichondrium of the auricular cartilage follows local trauma (e.g., ear piercing). The infection may closely resemble auricular cellulitis, although the lobule is less often involved in perichondritis.
- Treatment requires systemic antibiotics active against the most common etiologic agents, Pseudomonas aeruginosa and S. aureus, and typically consists of an antipseudomonal penicillin (e.g., piperacillin) or a penicillinase-resistant penicillin (e.g., nafcillin) plus an antipseudomonal quinolone (e.g., ciprofloxacin). Surgical drainage may be needed; resolution can take weeks.
- If perichondritis fails to respond to adequate treatment, consider noninfectious inflammatory etiologies (e.g., relapsing polychondritis).
- Otitis externa: a collection of diseases involving primarily the auditory meatus and resulting from a combination of heat and retained moisture, with desquamation and maceration of the epithelium of the outer ear canal. All forms are predominantly bacterial in origin; P. aeruginosa and S. aureus are the most common pathogens.
- Acute localized otitis externa: furunculosis in the outer third of the ear canal, usually due to S. aureus. Treatment consists of an oral antistaphylococcal penicillin (e.g., dicloxacillin, cephalexin), with surgical drainage in cases of abscess formation.
- Acute diffuse otitis externa (swimmer's ear): infection in macerated, irritated canals that is typically due to P. aeruginosa and is characterized by severe pain, erythema, and swelling of the canal and white clumpy discharge from the ear. Treatment includes cleansing of the canal to remove debris and use of topical agents (e.g., hypertonic saline, mixtures of alcohol and acetic acid, antibiotic preparations combining neomycin and polymyxin), with or without glucocorticoids to reduce inflammation.
- Chronic otitis externa: erythematous, scaling, pruritic dermatitis that usually arises from persistent drainage from a chronic middle-ear infection, other causes of repeated irritation, or rare chronic infections such as tuberculosis or leprosy. Treatment consists of identifying and eliminating the offending process; successful resolution is frequently difficult.
- Malignant or necrotizing otitis externa: a slowly progressive infection characterized by purulent otorrhea, an erythematous swollen ear and external canal, and severe otalgia out of proportion to exam findings, with granulation tissue present in the posteroinferior wall of the canal, near the junction of bone and cartilage
- This potentially life-threatening disease, which occurs primarily in elderly diabetic or immunocompromised pts, can involve the base of the skull, meninges, cranial nerves, and brain.
- P. aeruginosa is the most common etiologic agent, but other gram-negative bacilli, S. aureus, Staphylococcus epidermidis, Actinomyces, and Aspergillus have been reported.
- A biopsy specimen of granulation tissue (or deeper tissues) should be obtained for culture.
- Treatment involves systemic antibiotics for 6-8 weeks and consists of an antipseudomonal agent (e.g., piperacillin, ceftazidime), sometimes in combination with an aminoglycoside or a fluoroquinolone; antibiotic drops active against Pseudomonas, combined with glucocorticoids, are used as adjunctive treatment.
- Recurs in up to 20% of cases. Aggressive glycemic control in diabetic pts helps with treatment and prevention of recurrence.
Eustachian tube dysfunction, often in association with URIs, causes inflammation with a sterile transudate. Viral or bacterial superinfection often occurs.
- Acute otitis media: typically follows a viral URI, which can directly cause viral otitis media or, more commonly, predispose to bacterial otitis media
- Etiology: S. pneumoniae is isolated in up to 35% of cases; nontypable H. influenzae and M. catarrhalis are other common causes of bacterial otitis media. Concern is increasing about community-acquired methicillin-resistant S. aureus (MRSA) as an emerging etiologic agent. Viruses (e.g., respiratory syncytial virus, influenza virus, rhinovirus, enterovirus) have been recovered either alone or with bacteria in up to 40% of cases.
- Clinical manifestations: The tympanic membrane is immobile, erythematous, bulging, or retracted and can perforate spontaneously.
- Other findings may include otalgia, otorrhea, decreased hearing, and fever.
- In isolation, erythema of the tympanic membrane is nonspecific as it is common in association with inflammation of the upper respiratory mucosa.
- Treatment: Indications for antibiotic treatment and regimens are listed in Table 59-2 Guidelines for the Diagnosis and Treatment of Acute Otitis Media; antibiotic prophylaxis and surgical interventions offer little benefit in recurrent acute otitis media.
- Serous otitis media: Also known as otitis media with effusion, this condition can persist for weeks (e.g., acute effusions) or months (e.g., after an episode of acute otitis media) without signs of infection and is associated with significant hearing loss in the affected ear.
- The majority of cases resolve spontaneously within 3 months without antibiotic treatment.
- Antibiotic treatment or myringotomy with tympanostomy tubes is reserved for pts with bilateral effusions that have persisted for at least 3 months and are associated with significant bilateral hearing loss.
- Chronic otitis media: persistent or recurrent purulent otorrhea with tympanic membrane perforation, usually associated with conductive hearing loss
- Inactive disease, characterized by a central perforation of the tympanic membrane, is treated with repeated courses of topical antibiotic drops during periods of drainage.
- Active disease involves formation of a cholesteatoma that may enlarge and ultimately lead to erosion of bone, meningitis, and brain abscess; surgical treatment is required.
- Mastoiditis: accumulation of purulent exudate in the mastoid air cells that erodes surrounding bones and causes abscess-like cavities
- Pts have pain, erythema, and mastoid process swelling causing displacement of the pinna along with the signs and symptoms of otitis media.
- Rare complications include subperiosteal abscess, deep neck abscess, and septic thrombosis of the lateral sinus.
- Broad-spectrum empirical IV antibiotic regimens targeting S. pneumoniae, H. influenzae, and M. catarrhalis can be narrowed once culture results are available; mastoidectomy is reserved for pts with complicated cases or pts in whom medical management fails.