What are the next steps in managing a patient with suspected mastoiditis and potential neurological complications?

Management of Suspected Mastoiditis with Potential Neurological Complications

In a patient with suspected mastoiditis and potential neurological complications, immediate imaging with CT temporal bone with IV contrast should be performed, followed by MRI with contrast if intracranial complications are suspected, along with prompt initiation of intravenous broad-spectrum antibiotics and ENT consultation for possible surgical intervention. 1, 2

Initial Diagnostic Imaging

• CT temporal bone with IV contrast is the first-line imaging modality for suspected mastoiditis, as it provides high spatial resolution to assess intratemporal complications such as coalescent mastoiditis and bone erosion 1
• When neurological complications are suspected (headache, vertigo, meningismus, neck rigidity, seizures, or neurological deficits), MRI with contrast is superior to CT for evaluating intracranial spread 1, 2
• MRI with and without IV contrast is particularly indicated for suspected intracranial infections including meningitis, encephalitis, and brain abscess 1
• For suspected venous sinus thrombosis (a common complication of mastoiditis), MRV (magnetic resonance venography) is the imaging study of choice 1

Antibiotic Management

• Initiate intravenous broad-spectrum antibiotics immediately after obtaining cultures 2, 3
• Ceftriaxone is a commonly recommended antibiotic for mastoiditis with potential for intracranial complications 4, 3
• Consider combination therapy with vancomycin if there is concern for resistant organisms, particularly in the post-COVID era where more severe complications have been observed 5
• Monitor for potential adverse effects of ceftriaxone, including rash (1.7%), eosinophilia (6%), and rarely encephalopathy or seizures 4

Surgical Intervention

• Myringotomy with or without tympanostomy tube placement should be performed promptly to provide drainage and obtain cultures 2
• Surgical management is indicated if there is no improvement after 48 hours of appropriate intravenous antibiotic therapy 1, 2
• Immediate surgical intervention is required for:
  • Subperiosteal abscess formation 2
  • Evidence of intracranial complications (brain abscess, meningitis) 1, 2
  • Sigmoid sinus thrombosis 2, 6

Monitoring for Complications

• Close monitoring for clinical improvement is essential during the first 48 hours of treatment 2
• Intracranial complications that require vigilant monitoring include:
  • Meningitis, cerebritis, subdural empyema, or brain abscess 1, 6
  • Dural venous sinus thrombosis (especially in children with mastoiditis) 1, 6
  • Facial nerve palsy, seizures, and encephalitis 3
• Laboratory markers such as elevated C-reactive protein (>7.21 mg/dL) and high leukocyte count are associated with increased risk of complications and should prompt closer monitoring 7

Special Considerations

• Children under 24 months of age have a higher risk of complications (33% vs. 15% in older children) and require particularly close monitoring 7
• Obtain middle ear cultures whenever possible, as this can help reduce the use of broad-spectrum antibiotics by allowing targeted therapy 7
• Anticoagulation may be considered for sigmoid sinus thrombosis in the absence of contraindications 2
• Despite prior antibiotic treatment for acute otitis media, mastoiditis can still develop, with 33-81% of mastoiditis cases having received antibiotics previously 2

Pitfalls to Avoid

• Do not delay imaging if neurological symptoms are present, as intracranial complications can be clinically occult and potentially fatal 8
• Do not rely solely on non-contrast CT for evaluation of suspected encephalitis, as sensitivity is poor compared to MRI 1
• Do not discontinue antibiotics prematurely, even if initial clinical improvement is observed 2
• Do not overlook the possibility of negative cultures (occurring in 33-53% of cases), which emphasizes the importance of maintaining broad-spectrum empiric coverage 2