What are the symptoms of herpes encephalitis?

The symptoms of herpes encephalitis include dizziness, headache, and body pain in the early stages. As the disease progresses, symptoms of respiratory infection will appear. Later, the patient will experience symptoms such as impaired consciousness, convulsions, hemiplegia, and cranial nerve dysfunction.

1. The prodromal stage is characterized by dizziness, headache, body pain, etc., followed by symptoms of upper respiratory tract infection, and fever may reach 38-40℃. Only some cases develop skin herpes. This period usually does not exceed 2 weeks.

2. The manifestations of neuropsychiatric symptoms are varied. In the early stages, mental symptoms are often prominent, including personality changes, abnormal behavior, irrelevant answers, disorientation, hallucinations, delusions, amnesia, and aphasia, which may be caused by the early invasion of the temporal lobe, frontal lobe, and limbic system by the virus through the trigeminal nerve and olfactory bulb.

3. As the disease progresses, necrotic foci appear in brain tissue and the patient shows impaired consciousness. For example, drowsiness, lethargy, delirium, coma, etc.; convulsions, twitching, hemiplegia and cranial nerve dysfunction such as strabismus, anisocoria, hemianopsia, etc., accompanied by manifestations of intracranial hypertension. The patient has a stiff neck, increased muscle tone, and pathological reflexes. Some cases present with decerebrate rigidity in the early stages. In severe cases, brain herniation may occur.

4. Acute encephalomyelitis is mainly seen in infants under 1 year old, who are infected through the HSV-infected birth canal during birth. Intrauterine infection can cause diffuse brain damage or malformations.

5. EEG abnormalities may appear in the early stages of the disease. Typical changes are focal periodic sharp waves on a diffuse high-amplitude slow wave background; the temporal lobe and frontal lobe often show periodic spikes and slow waves. Brain CT and MRI examinations can show low-density lesions in the temporal and frontal lobes, accompanied by punctate hemorrhages and cerebral edema, and ventricular compression and displacement can be seen. Radionuclide brain scan showed increased uptake in the temporal and frontal lobes.