bubble_chart Overview

Both acute and chronic infections can invade through congenital cranial fissures or directly through bone destruction caused by sebaceous cysts. Hematogenous infection is also possible but less common. Depending on the sequence of infection layers, it can be classified into four types: outer layer inflammation of the dura mater, inner layer inflammation of the dura mater, leptomeningitis, and meningitis. The commonly referred otogenic meningitis is actually diffuse arachnoid leptomeningitis, which is the most common intracranial complication.

bubble_chart Clinical Manifestations

The onset is sudden, with severe headache, high fever, neck stiffness, nausea, vomiting, etc. Within 3–5 days, opisthotonos appears, superficial reflexes disappear, and pathological reflexes emerge. Delirium and unconsciousness can quickly develop. Lumbar puncture reveals very high intracranial pressure, and the cerebrospinal fluid is cloudy or even purulent.

bubble_chart Diagnosis

Based on the history of otitis media and signs of meningitis, along with cerebrospinal fluid analysis, the diagnosis is generally not difficult. In recent years, due to the widespread use of broad-spectrum antibiotics, acute symptoms are often suppressed, and cerebrospinal fluid chemical changes are minimal. Protein levels may slightly increase, while glucose and chloride levels remain within the normal range. There may be a slight increase in white blood cells. Particularly with improper treatment, it can evolve into focal or prolonged meningitis, which can easily be confused with mild tuberculous meningitis or epidemic cerebrospinal meningitis.

bubble_chart Treatment Measures

Use antibiotics with good blood-brain barrier penetration, such as penicillin 6-8 million units or sulfadiazine sodium 4-6g, administered intravenously via calm pulse drip. Perform a radical mastoid exploration to remove sebaceous cysts, granulation tissue, and necrotic bone, and to eradicate fistulas and congenital fissures invading the cranial cavity. Currently, intrathecal drug administration is rarely used due to its low drug concentration and frequent adverse reactions. Generally, the single dose of penicillin should not exceed 10,000 units. During the meningitis period, brain abscesses often occur, with an incidence rate of 2-7%. Therefore, after the symptoms of meningitis disappear, if space-occupying signs reappear, strict examination is necessary to confirm whether the meningitis is truly cured. Cerebrospinal fluid re-examination and CT brain scans can be used to rule out the possibility of brain abscesses, and close follow-up should be maintained after discharge. Antibiotics Suwen Before the era of sulfonamides and antibiotics Suwen, the mortality rate of otogenic meningitis was very high. Since the advent of sulfonamides and antibiotics, the mortality rate has dropped from 90% to below 5%. Nowadays, deaths are mostly caused by misdiagnosis, mistreatment, or complications such as brain abscesses.