BASICS
An inflammatory process of the mastoid air cells or posterior process of the temporal bone, most commonly a suppurative complication of acute otitis media (AOM) ‚
DESCRIPTION
- Acute mastoiditis typically presents following AOM or may be the first sign of AOM. Symptoms are present for <1 month.
- Subdivided into two stages
- Acute mastoiditis with periostitis: involves the mastoid periosteum with purulence in the mastoid air cells
- Acute mastoid osteitis (coalescent mastoiditis): destruction of bony septae separating air cells; leading to empyema and more serious head/neck complications
- Subacute mastoiditis (masked mastoiditis): indolent process, may occur with insufficiently treated AOM
- Chronic mastoiditis: due to failed treatment of chronic otitis media. Usually associated with cholesteatoma; symptoms last months to years.
EPIDEMIOLOGY
- Children > adults
- Most common in children <2 years of age
- In children: males > females
- Incidence is reduced after introduction of antibiotics but may again be increasing with rise of antibiotic-resistant Streptococcus pneumoniae. Introduction of PVC 13 vaccine may mitigate this rise (1)[C].
Incidence
1 to 4 cases/100,000 persons/year (2) ‚
ETIOLOGY AND PATHOPHYSIOLOGY
- Subclinical stage begins with AOM causing inflammation of mastoid air cells (likely present in all cases of AOM)
- Obstruction of the aditus ad antrum (connecting the tympanic cavity and mastoid)
- Blocks outflow tract of mastoid air cells
- Edema and accumulation of purulent material with penetration of periosteum (acute mastoiditis with periosteitis)
- Increased pressure from fluid within the air cells leads to destruction of bony septae (acute mastoid osteitis/acute coalescent mastoiditis).
- Acute mastoid osteitis can spread to adjacent areas in head and neck with abscess formation:
- Subperiosteal abscess (most common complication), Bezold abscess, suppurative labyrinthitis, suppurative CNS complications
- AOM: Haemophilus influenzae, S. pneumoniae
- Acute mastoiditis: Streptococcus pneumoniae (most common), Streptococcus pyogenes, H.influenzae, Staphylococcus aureus (including methicillin-resistant Staphylococcusaureus [MRSA])
- Chronic mastoiditis: Pseudomonas aeruginosa, S. aureus, Enterobacteriaceae, anaerobic bacteria, polymicrobials (3)
Genetics
No known genetic pattern ‚
RISK FACTORS
- Cholesteatoma
- Recurrent AOM or chronic suppurative otitis media
- Immunocompromised state
GENERAL PREVENTION
- Pneumococcal conjugate vaccine
- Early referral to ENT for chronic otitis media
- Appropriate diagnosis and treatment of AOM
- Prevention of recurrent AOM
- Treat chronic eustachian tube dysfunction (pressure equalization tubes).
- Identify cholesteatoma early.
DIAGNOSIS
HISTORY
- Most common symptoms in infancy (2)[A]
- Lethargy/malaise/irritability
- Fever
- Poor feeding/decreased appetite
- Otalgia/possible otorrhea
- Hearing loss
- Headache
- Pain/redness/swelling noted over mastoid.
- At time of admission (2)[A]
- 42% of children have history of otologic disease.
- 54% on antibiotic therapy
- Average duration of symptoms: 10 days
- Suspicion for mastoiditis increases when symptoms of AOM persist >2 weeks.
PHYSICAL EXAM
- Postauricular changes: erythema, tenderness, edema, and/or fluctuance (81 " “85%) (2)[A]
- Bulging, erythematous, or dull tympanic membrane (60 " “71%)
- Protrusion of auricle (79%)
- Fever (76%)
- Otorrhea if tympanic membrane is perforated
- Edema of external auditory canal
- Tympanic membrane (TM) can be normal in 10% of patients.
DIFFERENTIAL DIAGNOSIS
- Postauricular cellulitis or inflammatory adenopathy
- Severe otitis externa
- Benign neoplasm: aneurysmal bone cyst, fibrous dysplasia
- Malignant neoplasm: rhabdomyosarcoma, neuroblastoma
- Deep neck space infections
- Parotitis
DIAGNOSTIC TESTS & INTERPRETATION
Initial Tests (lab, imaging)
- CBC with differential: increased WBC count (4)[C]
- Elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) (3,4)
- Blood cultures
- Myringotomy/Tympanocentesis: Send for cultures, gram stain, acid-fast stain (2)[B].
- Mastoiditis is often a clinical diagnosis. CT confirms diagnosis and identifies regional complications.
- If obvious physical exam and/or historical findings are absent, temporal bone imaging is recommended for patients with cervical or postauricular findings (5).
- Plain radiographs of mastoid have low diagnostic yield but may show distortion of mastoid outline or clouding of mastoid air cells. These changes are not diagnostic and can also be seen in AOM.
- CT findings (97% sensitivity; 94% positive predictive value) (6)
- Clouding/opacification of air cells (also in AOM)
- Mastoid air cell coalescence
- Cortical bone erosion
- Rim-enhancing fluid collections
- CT of temporal bone with contrast helps identify suppurative extension (5)[C].
- Technetium-99m bone scan is more sensitive to osteolytic changes than CT.
- Indications for CT scan in children (6)[C]
- Neurologic signs
- Vomiting/lethargy
- Suspected cholesteatoma
- Fever after 48 to 72 hours of therapy
- Concern for local disease progression
- MRI use increasing; may see increased fluid signal of mastoid air cells on T2-weighted MRI " ”an incidental finding in the absence of clinical signs
Follow-Up Tests & Special Considerations
Interpret normal WBC with caution in symptomatic immunocompromised patients. ‚
Diagnostic Procedures/Other
- Tympanocentesis to obtain middle ear fluid for culture and sensitivity (2)[B]
- Myringotomy with culture (also therapeutic)
- Audiography if suspected hearing loss
- Obtain CSF if intracranial extension suspected.
- Biopsy tissue protruding through TM or tympanostomy tube
TREATMENT
- IV antibiotics and myringotomy ( ‚ ± tympanostomy tubes) is the preferred treatment for uncomplicated acute mastoiditis (reflecting a shift away from more invasive surgical treatment).
- Simple mastoidectomy is recommended for patients not responding to treatment after 3 to 5 days to avoid intracranial complications (7)[C].
GENERAL MEASURES
- Inpatient care during acute phase for IV antibiotics
- Keep the affected ear dry.
MEDICATION
First Line
- Empiric antibiotics against most common organisms: Streptococcus pneumoniae (including multiple resistant strains), Streptococcus pyogenes, Staphylococcus aureus (including MRSA), P. aeruginosa
- Use combination therapy with 3rd generation cephalosporin (ceftriaxone or cefotaxime) plus clindamycin with additional coverage for resistant strains (5,7)[C].
- Ceftriaxone 1 to 2 g IV q24h
- Pediatric dosing: 50 to 75 mg/kg/day IV divided q12 " “24h
- Precaution: Adjust dose with renal impairment.
- Clindamycin for coverage of ceftriaxone-resistant S. pneumoniae in pediatric patients (5)[C]:
- Clindamycin pediatric dosing: 20 to 40 mg/kg/day IV divided q6 " “8h
- Cefotaxime 1 to 2 g IV q4 " “8h, depending on severity
- Pediatric dosing: 100 to 200 mg/kg/day divided q6 " “8h
- Add vancomycin 30 to 60 mg/kg/day divided q8 " “12h if concerned for MRSA:
- Pediatric dosing: 15 mg/kg/dose q6 " “8h
- Precaution: adjust dose with renal impairment.
- For patients with a history of recurrent AOM or recent antibiotic administration, treat with piperacillin " “tazobactam 3.375 g IV q6h:
- Pediatric dosing: 300 mg/kg/day based on piperacillin component divided q6 " “8h
- For other significant contraindications, precautions, or interactions, please refer to the manufacturer 's literature.
Second Line
- Oral antibiotics are given after 7 to 10 days of IV antibiotics and once myringotomy/blood cultures identify pathogen and sensitivities. Common oral antibiotics include:
- Amoxicillin " “clavulanate (Augmentin) or clindamycin + 3rd-generation cephalosporin for 3 weeks or total treatment duration of 4 weeks
- For chronic mastoiditis: Use topical drops, ofloxacin otic solution (0.3%) or neomycin, polymyxin B, hydrocortisone three drops, 3 to 4 times per day.
ISSUES FOR REFERRAL
Consult ENT for mastoiditis in adults and children. ‚
SURGERY/OTHER PROCEDURES
- Perform tympanocentesis to obtain cultures and guide antibiotic choice (2)[B].
- Myringotomy and tympanostomy tubes allow drainage of middle ear (7)[C].
- Mastoidectomy is a definitive treatment for patients who fail to improve within 24 to 48 hours despite IV antibiotics and myringotomy and for those with meningeal or intracranial complications (6,7)[C].
- Simple mastoidectomy is most effective for management of subperiosteal abscesses, if a trial of conservative therapy with drainage, myringotomy, and IV antibiotics fails (8)[C].
- Clean ear canal under microscope to ensure pressure-equalization tube patency and adequate drainage of middle ear.
- Topical antibiotic drops usually used after insertion of pressure-equalization tubes.
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
- Clinical or imaging evidence of acute mastoiditis
- Hospitalize patients with acute mastoiditis and start IV antibiotics immediately.
Nursing
Avoid getting affected ear wet. ‚
Discharge Criteria
- Afebrile for 48 hours before IV antibiotics are discontinued
- Clinical improvement
- Able to take oral antibiotics
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
- Oral antibiotics for 3 weeks following course of IV antibiotics (total duration of antibiotics is 4 weeks)
- For chronic mastoiditis, consider several months of antimicrobial prophylaxis with amoxicillin.
Patient Monitoring
- Assess for hearing loss postoperatively (audiogram) after acute condition has subsided.
- Follow-up with ENT, particularly patients with intracranial complications or hearing loss
PATIENT EDUCATION
Avoid getting the affected ear wet. ‚
PROGNOSIS
- Depends on severity and stage of disease
- Conductive hearing loss may require reconstructive surgery.
- Most cases of mastoiditis recover fully if the diagnosis is made early and treated appropriately.
COMPLICATIONS
Total estimated complication rate is 18% (3). ‚
- Extracranial
- Subperiosteal abscess (most common)
- Bezold abscess (abscess of sternocleidomastoid muscle, insidious, risk of mediastinitis)
- Citelli abscess (osteomyelitis of the calvaria)
- Osteomyelitis of the temporal bone
- Suppurative labyrinthitis (resulting in deafness)
- Facial nerve paralysis
- Intracranial
- Intracranial abscess: epidural/subdural/cerebral
- Meningitis/cerebritis/periosteitis
- Gradenigo syndrome (palsy of the 6th cranial nerve, draining ear, and retro-orbital pain)
- Sigmoid sinus thrombophlebitis
- Central venous sinus thrombosis
REFERENCES
11 Tamir ‚ SO, Roth ‚ Y, Dalal ‚ I, et al. Acute mastoiditis in the pneumococcal conjugate vaccine era. Clin Vaccine Immunol. 2014;21(8):1189 " “1191.22 van den Aardweg ‚ MT, Rovers ‚ MM, de Ru ‚ JA, et al. A systematic review of diagnostic criteria for acute mastoiditis in children. Otol Neurotol. 2008;29(6):751 " “757.33 Chien ‚ JH, Chen ‚ YS, Hung ‚ IF, et al. Mastoiditis diagnosed by clinical symptoms and imaging studies in children: disease spectrum and evolving diagnostic challenges. J Microbiol Immunol Infect. 2012;45(5):377 " “381.44 Bilavsky ‚ E, Yarden-Bilavsky ‚ H, Samra ‚ Z, et al. Clinical, laboratory, and microbiological differences between children with simple or complicated mastoiditis. Int J Pediatr Otorhinolaryngol. 2009;73(9):1270 " “1273.55 Lin ‚ HW, Shargorodsky ‚ J, Gopen ‚ Q. Clinical strategies for the management of acute mastoiditis in the pediatric population. Clin Pediatr (Phila). 2010;49(2):110 " “115.66 Bakhos ‚ D, Trijolet ‚ JP, Morini ƒ ¨re ‚ S, et al. Conservative management of acute mastoiditis in children. Arch Otolaryngol Head Neck Surg. 2011;137(4):346 " “350.77 Psarommatis ‚ IM, Voudouris ‚ C, Douros ‚ K, et al. Algorithmic management of pediatric acute mastoiditis. Int J Pediatr Otorhinolaryngol. 2012;76(6):791 " “796.88 Psarommatis ‚ I, Giannakopoulos ‚ P, Theodorou ‚ E, et al. Mastoid subperiosteal abscess in children: drainage or mastoidectomy? J Laryngol Otol. 2012;126(12):1204 " “1208.
ADDITIONAL READING
- Minks ‚ DP, Porte ‚ M, Jenkins ‚ N. Acute mastoiditis " ”the role of radiology. Clin Radiol. 2013;68(4):397 " “405.
- Pritchett ‚ CV, Thorne ‚ MC. Incidence of pediatric acute mastoiditis: 1997 " “2006. Arch Otolaryngol Head Neck Surg. 2012;138(5):451 " “455.
CODES
ICD10
- H70.90 Unspecified mastoiditis, unspecified ear
- H70.009 Acute mastoiditis without complications, unspecified ear
- H70.099 Acute mastoiditis with other complications, unspecified ear
- H70.10 Chronic mastoiditis, unspecified ear
- H70.013 Subperiosteal abscess of mastoid, bilateral
- H70.011 Subperiosteal abscess of mastoid, right ear
- H70.12 Chronic mastoiditis, left ear
- H70.091 Acute mastoiditis with other complications, right ear
- H70.13 Chronic mastoiditis, bilateral
- H70.003 Acute mastoiditis without complications, bilateral
- H70.092 Acute mastoiditis with other complications, left ear
- H70.11 Chronic mastoiditis, right ear
- H70.019 Subperiosteal abscess of mastoid, unspecified ear
- H70.91 Unspecified mastoiditis, right ear
- H70.002 Acute mastoiditis without complications, left ear
- H70.92 Unspecified mastoiditis, left ear
- H70.001 Acute mastoiditis without complications, right ear
- H70.093 Acute mastoiditis with other complications, bilateral
- H70.012 Subperiosteal abscess of mastoid, left ear
- H70.93 Unspecified mastoiditis, bilateral
ICD9
- 383.9 Unspecified mastoiditis
- 383.00 Acute mastoiditis without complications
- 383.02 Acute mastoiditis with other complications
- 383.1 Chronic mastoiditis
- 383.01 Subperiosteal abscess of mastoid
SNOMED
- 52404001 mastoiditis (disorder)
- 335846001 Acute mastoiditis without complications
- 111538005 Acute mastoiditis with complication
- 80645004 chronic mastoiditis (disorder)
- 109910003 Chronic suppurative mastoiditis
- 72102005 Subperiosteal abscess of mastoid
- 109909008 Acute suppurative mastoiditis
CLINICAL PEARLS
- Suspect mastoiditis when symptoms of AOM persist >2 weeks despite a normal-appearing TM.
- Hospitalize all patients with acute mastoiditis for IV antibiotics. Consult ENT for drainage procedure.
- Treat with broad-spectrum IV antibiotics; collect middle ear fluid cultures to guide-specific therapy.
- If conservative treatment fails after 3 to 5 days, perform mastoidectomy to avoid intracranial complications.