A 4-year-old boy is brought to the clinic for worsening ear pain that started after completing a course of antibiotics for otitis media 2 weeks ago. For the past several nights, he has also been awakened by headaches; however, he feels better after vomiting in the morning. The patient has had recurrent ear infections since infancy but no other medical problems. Temperature is 38 C (100.4 F), blood pressure is 100/60 mm Hg, pulse is 95/min, and respirations are 18/min. Physical examination reveals an irritable child. Funduscopic examination is normal and extraocular motion is intact. The left tympanic membrane is bulging, erythematous, and opaque. The left mastoid is tender, erythematous, and swollen. Complete blood count results are as follows:
| Leukocytes | 17,000/mm3 |
| Neutrophils | 80% |
| Lymphocytes | 15% |
| Monocytes | 2% |
Which of the following is the best next step in management of this patient?
Mastoiditis | |
Pathophysiology |
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Clinical findings |
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Management |
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Complications |
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This patient has nocturnal headaches and morning vomiting, red flags for intracranial pathology. His coexisting otitis media and mastoiditis suggest direct spread of bacterial infection and formation of a temporal brain abscess.
Brain abscesses most commonly present with severe headache that is not relieved by nonsteroidal anti-inflammatory drugs. Headache may be positional and worse at night because intracranial pressure (ICP) naturally increases in the supine position due to gravity. Increased ICP from associated cerebral edema also stimulates the receptors in the medullary vomiting center and the area postrema. Although papilledema is a sign of elevated ICP, it takes days to develop and is seen only in a minority of patients with brain abscess. Fever and focal neurologic deficits are also present in approximately half of patients.
The next step in management of suspected brain abscess is contrast-enhanced CT scan or MRI of the brain. CT scan is faster and more readily available; however, MRI is more sensitive for early cerebritis and does not use ionizing radiation. Neuroimaging demonstrates a ring-enhancing lesion in the left temporal lobe and surrounding edema, which is consistent with brain abscess.
(Choice A) Treatment of brain abscess includes needle aspiration and/or surgical excision, followed by prolonged administration of parenteral antibiotics.
(Choice B) This patient has nocturnal headaches and morning vomiting, which are concerning for elevated ICP. Therefore, lumbar puncture is contraindicated due to the risk of cerebral herniation and death. Brain imaging must be performed first.
(Choice C) Although this patient may need a mastoidectomy to treat mastoiditis, he should first undergo neuroimaging to evaluate for intracranial extension of the infection.
(Choice E) Skull x-ray is useful for detecting fractures, particularly in the setting of head trauma, but is not useful for evaluating brain tissue in patients with suspected intracranial infection.
Educational objective:
Direct spread of bacteria from otitis media or mastoiditis can cause a temporal brain abscess. The presentation can include severe headache, morning vomiting, fever, and focal neurologic deficits. Diagnosis is confirmed by visualization of a ring-enhancing lesion on CT scan or MRI of the brain.