Herpetic encephalitis

Description:

Herpetic encephalitis - the acute damage of a brain caused by a herpes simplex virus is more often than type 1 (VPG-1), is more rare than type 2 (VPG-2). Most of researchers consider it as a complication of a herpes infection.

Seasonal fluctuations are not inherent to herpetic encephalitis. Two peaks of incidence fall on 5-30 years and age 50 years are more senior. More than in 95% of cases as the causative agent of herpetic encephalitis serves the virus of a herpes simplex of type 1.

Symptoms of Herpetic encephalitis:

Except typical necrotic encephalitis allocate a pseudo-tumorous and trunk form. Also encephalomyelitis and a generalized herpes infection with preferential defeat of TsNS are described.

Characteristic triad of herpetic encephalitis - the acute feverish beginning, development of spasms of jacksonian type and disturbance of consciousness developing usually after a short-term respiratory infection. Sometimes sudden development of spasms and a loss of consciousness precede fever. Focal manifestations meet in the form of paresis of third cranial nerves, a hemiparesis and various aphasias. In the first 3-5 days of a disease the composition of cerebrospinal fluid can be normal. Further the lymphocytic pleocytosis (30-400 x 109/l) and the increased protein content are found (to 1,32 g/l). In blood the leukocytosis (to 20 x 109/l) with band shift, a lymphopenia and high SOE comes to light. Coma - an adverse predictive sign. The lethality before use of antiherpetic himiopreparat reached 70-75%, now makes 20-25%. Specific weight of the residual phenomena in the form of convulsive attacks, permanent intellectual disturbances of the stationary and progressing character is high. At babies also hydrocephaly and a decortication of a brain develop. The clinical diagnosis is verified by the virologic and immunological researches directed to detection of VPG antigen and specific antibodies, including class J immunoglobulins in blood serum and cerebrospinal fluid.

Reasons of Herpetic encephalitis:

The activator concerns to family of herpes (Herpes viridae). E is family also viruses of chicken pox, shingles, cytomegaloviruses and the activator of an infectious mononucleosis enter. Contains DNA, the sizes of virion of 100-160 nanometers. The virus genome is packed into the capsid of the correct form consisting of 162 capsomeres. The virus is covered with a lipidsoderzhashchy cover. Breeds intracellularly, forming intranuclear inclusions. Penetration of a virus into some cells (for example, in neurons) is not followed by replication of a virus and death of a cell. On the contrary, the cell exerts the oppressing impact and a virus passes into a condition of a latention. After a while there can be a reactivation that causes transition of latent forms of an infection to manifest. On an antigenic structure viruses of a herpes simplex are subdivided into two types. Genomes of viruses of the 1 and 2 type for 50% are homologous. The virus of the 1st type causes preferential defeat of respiratory bodies. Developing of genital herpes and generalized infection of newborns is connected with a virus of a herpes simplex of the 2nd type.

Epidemiology. Herpetic encephalitis makes 11,5% among acute encephalitis. Children of younger age get sick more often. Incidence is sporadic, some researchers point to increase it in the spring. The infection can be transmitted in the drop and contact way.

Treatment of Herpetic encephalitis:

The patients having herpetic encephalitis are hospitalized in chambers of an intensive care in connection with danger of respiratory frustration also by dysphagies. It is widely used antiviral химиопрепарат an acyclovir (zovirax, виролекс) in tablets and ampoules which at comas is appointed on 10-15 mg/kg to one introduction each 8 hours. A course of treatment - 7-12 days. At the same time appoint interferona and immunomodulators, and also corticosteroids (dexamethasone or Dexasonum, to 1-2 mg/kg is each 6 hours). A course of treatment - 6-8 days.