Some auxiliary examinations are very necessary for pediatric encephalitis, which help in the diagnosis and differential diagnosis of encephalitis. The main tests generally include the following: First, an electroencephalogram (EEG), which is the most commonly used examination. It is safe, non-invasive, and relatively accurate. Children with encephalitis will show light to moderate abnormalities in the EEG. Combined with the patient's history of fever and headache, it has important clinical significance for the diagnosis of encephalitis. The second important examination is cranial magnetic resonance imaging (MRI). If the encephalitis is severe, pathological changes in the cerebrospinal fluid can be seen on MRI. The third very important examination is lumbar puncture. Lumbar puncture can mainly determine the pressure of the cerebrospinal fluid, the color of the cerebrospinal fluid, and analyze the levels of white blood cells, glucose, and chloride in the cerebrospinal fluid. This is crucial for diagnosing encephalitis and excluding other types of encephalitis.