Sporadic encephalitis, also known as sporadic sexually transmitted disease encephalitis, nonspecific encephalitis, and atypical encephalitis, commonly presents with emotional disturbances, intellectual impairments, thought disorders, and behavioral abnormalities. Mental disorders often coexist with disturbances of consciousness.

bubble_chart Clinical Manifestations

Some patients experience prodromal symptoms, such as headache, fatigue, poor appetite, vomiting, sleep disturbances, or decreased mental activity a few days before onset. The disease may manifest acutely or subacutely, with common initial symptoms including psychiatric disorders, paralysis, headache, fever, impaired consciousness, nausea and vomiting, and epileptic spasms.

Emotional disturbances (emotional instability, apathy, depression, euphoria, fear), cognitive impairments (decline in comprehension, memory, calculation, judgment, and associative abilities), thought disorders (mutism, logorrhea, incoherent speech, and delusions), and behavioral disturbances (decreased or increased activity, impulsivity, stupor) are frequently observed. Psychiatric disorders often coexist with impaired consciousness (delirium, confusion, clouding of consciousness). Based on the predominant psychiatric symptoms, patients can be classified into subtypes such as catatonic-like syndrome, schizophrenia-like syndrome, or dementia-like syndrome. During the progression of the disease, psychiatric manifestations may change, such as shifting from psychomotor agitation to psychomotor inhibition. Neurological signs, such as hemiplegia or positive pyramidal signs, are generally detectable during the course of the illness. Laboratory tests, including cerebrospinal fluid analysis, electroencephalography (EEG), evoked potentials, cranial CT, and MRI, often show certain abnormalities, which can help differentiate the condition from non-organic psychiatric disorders like affective psychosis or schizophrenia.

1. Acute or subacute onset, with symptoms usually peaking within 1 to 2 weeks. There is often a history of infection prior to the illness.

2. Psychiatric symptoms can occur at any stage of the disease, manifesting as:

(1) Disturbance of consciousness is the most common, often presenting as drowsiness, confusion, clouding, delirium, or disorientation.

(2) Hallucinations, delusions, talking to oneself or mutism, emotional instability or apathy, neglect of personal hygiene, refusal to eat, negativism, stupor, or aggressive behavior; severe cases may exhibit schizophrenia-like symptoms.

(3) Cognitive impairment or a dementia-like state.

3. In the prodromal stage, epileptic seizures are relatively common, followed by paralysis, tremor, involuntary movements, ataxia, meningeal irritation signs, and signs of increased intracranial pressure. Profuse sweating is also one of the characteristic features of this condition.

4. Cerebrospinal fluid shows grade I elevation in protein and white blood cells. Electroencephalography (EEG) reveals diffuse abnormalities dominated by high-amplitude slow waves.

5. Exclusion of major psychotic disorders and psychiatric disturbances caused by infections, poisoning, or other organic brain diseases.

bubble_chart Treatment Measures

Treatment primarily focuses on addressing the disease cause. For psychiatric symptoms, benzodiazepine anti-anxiety medications or low-dose antipsychotics can be used. For prolonged cases, insulin hypoglycemic therapy may be attempted, but electroconvulsive therapy is contraindicated.