Basic medical data of medical recruitment examination: pathological changes of epidemic cerebrospinal meningitis and Japanese encephalitis?

In the examination of public institutions, the content of pathological nervous system diseases is less, and the test sites mainly focus on the pathological manifestations of epidemic cerebrospinal meningitis and Japanese encephalitis. Today, we will summarize the relevant pathological manifestations of epidemic cerebrospinal meningitis and Japanese encephalitis, which is convenient for everyone to remember and judge.

I. Concept

1, epidemic cerebrospinal meningitis is acute purulent meningitis caused by meningococcal infection. Most of them are sporadic, which can cause epidemic in winter and spring, so it is called epidemic cerebrospinal meningitis.

2. Japanese encephalitis is an acute infectious disease caused by Japanese encephalitis virus infection. The disease first occurred in Japan, and it usually occurs in summer and autumn, also known as Japanese summer encephalitis. It is also called Japanese encephalitis because it is different from Japanese encephalitis that sleeps in winter. The disease is acute, serious and has a high mortality rate. The clinical manifestations are high fever, lethargy, convulsion and coma.

Second, the pathological changes of epidemic cerebrospinal meningitis

1. Upper respiratory tract infection period

The main pathological changes are mucosal congestion, edema, infiltration and secretion of a small number of neutrophils. 1? Two days later, some patients entered the stage of sepsis.

2. Septicemia stage

Most patients have petechiae (spot) on their skin and mucosa, which is the bleeding focus caused by bacterial embolism and endotoxin damage in small blood vessels. Bacteria can often be found here after scraping. Blood culture during this period can be positive. Due to the effect of endotoxin, patients may have high fever, headache, vomiting and neutrophil increase in peripheral blood.

3. Meningitis

The characteristic lesion at this stage is purulent inflammation of the meninges. Microscopically, the arachnoid blood vessels are highly dilated and congested, the subarachnoid space is widened, and a large number of neutrophils, serous fluid and cellulose exudation and a small number of lymphocytes and monocytes infiltration can be seen. With Gram staining, pathogenic bacteria can be found inside and outside cells. The brain parenchyma is generally not involved, and the adjacent cerebral cortex may have mild edema. In severe cases, the brain parenchyma adjacent to meninges can be involved, which makes neurons degenerate, which is called meningoencephalitis. Severe pathological changes will cause vasculitis and thrombosis, leading to cerebral parenchymal ischemia and infarction.

Third, the pathological changes of Japanese encephalitis

The pathological changes widely involve the parenchyma of brain and spinal cord, causing degeneration and necrosis of nerve cells, proliferation of glial cells and infiltration of inflammatory cells around blood vessels, which belongs to degenerative inflammation. The cerebral cortex, basal nucleus and thalamus were the most seriously damaged. Cerebellar cortex, thalamus and pons followed; Spinal cord lesions are the lightest and are often confined to the cervical spinal cord.

Macroscopically, the pia mater is hyperemia and edema, the gyrus is widened, and the sulcus is narrow and shallow. In severe cases, there are scattered punctate bleeding in the brain parenchyma, and translucent softening foci with large millet or needle tip can be seen, with clear boundaries, diffuse distribution or clustering in groups, which are generally most obvious in the parietal lobe and thalamus.