HORIOMENINGYT LYMPHOCYTIC (choriomeningitis lympho-cytica; synonym: acute lymphocytic benign meningitis, choriomeningitis lymphocytica benigna) — the infectious disease which is characterized by a serous inflammation of a meninx of a brain and vascular textures of cerebral cavities.
Diseases of X. l. are observed in the majority of the countries of Europe, Asia, North and South America. Considerable infectiousness virus X. l. house mice the possibility of almost universal infection of the person causes. There are scanty data on spread of a virus in Africa. In the USSR cases of X. l. are registered since 1948.
Etiology. Virus X. l. it is allocated by Armstrong (Ch. J. Armstrong) in 1934 during the studying of encephalitis in St. Louis (USA), however its value in an etiology of encephalitis at that time remained obscure. Further etiological connection of the allocated virus with acute X was established. l. In a crust, time virus X. l. carry to the sort Arenavirus this. Arenaviridae (see Arenovi-rusa).
Epidemiology. Main source of a virus X. l. the house mouse is. A carriage of virus is revealed also at hamsters, dogs and Guinea pigs. Frequency of infection of the person with a virus X. l. is in direct dependence on its distribution in populations of house mice, at to-rykh develops hron. asymptomatic infection; mice allocate a virus with urine, excrements, a nasal secret, contaminating foodstuff, water and household goods. The virus can be in the dried excrement.
Incidence is more often sporadic. However also limited epidemic flashes are possible. So, from December, 1973 to April, 1974 in the USA 181 cases of X are registered. l., connected with sale to the population of the hamsters who were infected with a virus X. l. More often the disease is observed in rural areas during the winter and spring period that is explained by the seasonal migration of mice leading to closer contact of the population with them. Persons of all age groups are ill. True distribution of X. l. it is unknown since not all patients with serous meningitis are inspected on this disease. At mass inspections of country people quite often find the specific antibodies indicating the postponed infection.
Pathogeny. Ideas of a pathogeny of X. l. have fragmentary character. The virus gets into an organism through upper respiratory tracts, went. - kish. the path and the damaged integuments, reaches regional lymph nodes where there is its reproduction. The subsequent penetration of a virus into cells of reticuloendothelial system (see System of mononuclear phagocytes) leads to oppression of their function, in particular an immune response on a virus, than late emergence of serumal antibodies and duration of Viru of the semiya (see) arising from the first days of a disease speak. The mechanism of selective defeat of a soft cover of a brain (see the Meninx) and vascular textures (see) cerebral cavities remains not studied. During development of a meningeal syndrome the virus in large numbers is found in cerebrospinal liquid. In a pathogeny of X. l. an essential role is played by increase in intracranial pressure (see).
Pathological anatomy. The expressed hypostasis, a hyperemia and diffusion lymphoid infiltration of a soft cover of a brain, signs of the increased intracranial pressure (accumulation of cerebrospinal liquid in a subarachnoid space and ventricles), inflammatory changes in vascular textures of cerebral cavities are noted. Hypostasis, a hyperemia and lymphocytic infiltration are observed also in lungs and a liver.
And the m of m at N and t e is studied by t a nedosta - precisely. Virus neutralizing antibodies are found at had within 3 years and more.
Clinical picture. Incubation interval of 6 — 13 days. The disease begins sharply with a fever and bystry temperature increase. There are two a wedge, forms X. l.: grippopodobny, or all-feverish, and meningeal. At a grippopodobny form of a disease in a wedge, a picture the indisposition, head and muscular pains, cold, bronchitis prevail. Recovery occurs within several days.
At a meningeal form the picture of serous meningitis joins the symptoms stated above (see). The constant sharp headache is observed, the photophobia, a hyperesthesia, vomiting, a sleep disorder, a stiff neck, Kernig's signs (see Kerni-ga a symptom), Brudzinsky (see Meningitis, a meningeal syndrome), etc. appear. Often at patients unsharp developments of stagnation on an eyeground are noted. The optic neuritis is described. Pressure of cerebrospinal liquid is increased to 300 — 400 mm w.g., a pleocytosis from several hundred to 1000 cells and more in 1 mkl with dominance of lymphocytes (see. Cerebrospinal liquid). During the involvement in patol. process of these or those sites of a brain develops an encephalomeningitis (see Mieningguo a coccal infection). Duration of fever and meningeal symptoms makes 1 — 2 week more often. Decrease in temperature usually lytic. In some cases the meningeal syndrome is expressed to 4 — week, is long subfebrile condition is noted. Disease is usually high-quality, with rather bystry disappearance of symptoms, without the residual focal phenomena.
The diagnosis is based on data a wedge, pictures and results of laboratory researches. The virus can be allocated from blood and from cerebrospinal liquid during the acute period of a disease for what to white mice enter into a brain the studied material (see. In and rusologichesky researches). Antibodies find in reaction of an immunofluorescence (see) and fixations of the complement (see Reaction of binding complement). Virus neutralizing antibodies at patients of X. l. appear in blood serum on 3 — the 4th week and later.
Differential diagnosis of a meningeal form X. l. carry out with meningitis of other etiology (see Meningitis, t. 20, additional materials), iyersiniozy (see), at a grippopodobny form — with acute respiratory diseases (see. Respiratory viral diseases), a mononucleosis (see the Mononucleosis infectious).
L e h e N and e. Specific therapy is not developed. Carry out a symptomatic treatment (anesthetics), in more hard cases appoint disintoxication and dehydrational means. A spinal puncture (see), to-ruyu carry out with the diagnostic purpose, yields good therapeutic result.
Forecast, as a rule, favorable.
Prevention: extermination of house mice in dwellings and settlements (see Deratization), protection of foodstuff and water from pollution by their rodents.
Bibliogrg r e of of M. The flashes of a lymphocytic choriomeningitis registered in the USA in recent years Bulletin WHO, t. 52, M 4, p. 2, page 543, 1976; 3 l y d-N and to about in D. M., To and z and N of c e in A. P. and Starshovp. D. Therapy of viral diseases, page 252, L., 1979; The Management on a zoonosis, under the editorship of V. I. Pokrovsky, page 73, JI., 1983; C at to e r M. B. Clinical neuropathology of children's age, page 23, M., 1978. V. I. Pokrovsky.