What is a neuroinfection and how to recognize it? Neuroinfection of the brain: causes, manifestations and treatment Consequences of a neuroinfection, symptoms.

Infectious lesions nervous system in adults and children are combined under the term “neuroinfection”. Diseases can be caused by various pathogens. Symptoms are characterized by intoxication manifestations, meningeal and focal neurological disorders. Examination of patients includes instrumental and laboratory research. Treatment uses an etiotropic approach, which consists in eliminating the cause of the pathology, and symptomatic medications.

Causes of development of infectious lesions

Damage to the central nervous system during neuroinfections is associated with the penetration of infectious agents into its structures. They can be individual bacteria, viral microorganisms, fungi or protozoa. Infection occurs from a sick person or carrier who may have no symptoms of the disease. The following routes of infection are known:

1. Contact-household - typical for a number of viral infections, for example, herpes or polio.
2. Airborne. Transmission of infectious agents occurs when talking to a patient, sneezing or coughing. This mechanism is typical for viral and bacterial infections.
3. The sexual tract is specific for syphilis and HIV infection. Infection is associated with sexual contact, when microorganisms can pass through the mucous membranes of the genital organs.
4. Fecal-oral mechanism - infection occurs through food or water. This path can lead to infection with intestinal viruses, botulism, polio, etc.

In addition to the routes of transmission of microorganisms, predisposing factors are of great importance in the occurrence of brain infections. In neurology, these include: previous traumatic brain injuries, immunodeficiency, severe pathology internal organs, frequent contact with infectious patients, etc.

Each type of pathogen has its own developmental characteristics. However clinical syndromes Regardless of the root cause of the disease, they are associated with specific changes in the body. Meningeal signs occur against the background of inflammation of the meninges and increased intracranial pressure. If infectious agents affect the centers of the autonomic nervous system, autonomic disorders occur varying degrees expressiveness. Focal neurological symptoms are characteristic of damage to areas of the brain as a result of the development of an inflammatory reaction and necrotic processes. Bacterial and viral neuroinfections are characterized by intoxication phenomena caused by the development of inflammation and the immune response.

Types of neuroinfections

Classification is necessary for prescribing standard and effective treatment. There are several approaches to dividing the disease. The main classification is based on the location of the lesion:

• - damage to the nervous tissue of the central nervous system structures. Focal neurological symptoms and signs of intoxication predominate. Tick-borne encephalitis is often detected, as well as those associated with the herpes virus, chickenpox and rubella.
• Meningitis - manifests itself as inflammatory changes in the meninges. Patients experience cerebral and meningeal symptoms against the background of severe intoxication phenomena. If the disease is caused by viruses or the causative agent of tuberculosis, meningitis is serous in nature. With bacterial or fungal infection, a purulent type of meningitis is noted.

There are also specific forms of neuroinfections: polio, abscesses, neurosyphilis, herpes zoster, botulism and neuroAIDS. They are characterized by the development pathological changes in certain structures of the central nervous system against the background of infection with a specific microorganism.

Depending on the course of the disease, a diagnosis of acute, subacute or chronic neuroinfection is made. Types of the disease differ in the nature of the onset of symptoms, the duration of their persistence in the patient and the consequences for his body.

Clinical manifestations

Symptoms vary and depend on the specific type of disease. IN clinical picture There are several syndromes:

• intoxication;
• meningeal;
• focal neurological;
• liquorodynamic;
• vegetative-vascular.

Intoxication syndrome

It occurs during a purulent process, but can also accompany serous meningitis. It is manifested by a sharp increase in temperature to 39.5°C or more in the acute form and up to 38°C in the chronic form, headache, general weakness, as well as dyspeptic symptoms in the form of stool disorders. Fever causes tachycardia and fluctuations in blood pressure. IN childhood convulsive readiness is noted and febrile convulsions are possible.

Meningeal lesion

Clinical manifestations are associated with damage to the membranes of the brain, which leads to a triad of symptoms: radicular, muscular-tonic and cerebral disorders. General cerebral symptoms are manifested by a headache without a clear localization of a bursting nature. Patients cannot tolerate loud sounds and bright lights, and photophobia gradually develops. Characteristic sign general cerebral disorders - vomiting, which is not accompanied by nausea. As a result of diffuse brain damage, changes in consciousness are possible, including coma.

Mental disorders during neuroinfections are manifested by delusions, hallucinations and other disorders. When involved in inflammation of the roots spinal cord, meningeal symptoms develop - tension in the neck muscles in the occipital area, Brudzinski's, Kernig's signs, etc. All of them are associated with disturbances in the tone of the muscle groups of the body.

Liquorodynamic syndrome

Disturbances in the outflow of cerebrospinal fluid lead to increased intracranial pressure. The patient experiences a feeling of stupor and stupor, as well as seizures. With increasing intracranial hypertension, dislocation of the brain may develop with its wedging in the openings of the skull. This condition requires immediate neurosurgical assistance, as it is accompanied by high mortality.

Autonomic-vascular disorders

They are divided into 3 main types:

1. Vagoinsular - there is a decrease in heart rate, a decrease in blood pressure and increased diuresis.
2. Sympathoadrenal - manifested by hypertension, tachycardia, sweating and thirst.
3. Mixed - combines the symptoms of the previous two forms.

Focal neurological signs of neuroinfection

Depends on the location of the lesion in the brain. With inflammatory changes in the area of ​​the occipital cortex, visual disturbances are observed: a decrease in visual acuity, the appearance of double vision, loss of individual visual fields, etc. If microorganisms predominantly affect the posterior parts of the frontal cortex, paresis and paralysis may occur, characterized by a decrease or complete disappearance of muscle strength, respectively.

Chronic or slow neuroinfections are characterized by mild symptoms. Patients may notice constant weakness, fatigue, cognitive impairment (decreased memory, ability to concentrate). This can lead to misdiagnosis and incorrect therapy. With exacerbation of chronic pathologies, the symptoms are similar to acute lesions.

Complications of the disease

The progression of pathology against the background of the absence or incorrect selection of therapy can lead to negative consequences:

• swelling of the brain and its dislocation against the background of increased intracranial pressure (such a condition poses a threat to the patient’s life, since when the brain is displaced, the structures of the central nervous system can be damaged);
• neurological deficit associated with damage to certain areas of the cerebral cortex or subcortical structures (this can cause the patient’s disability due to paralysis, etc.).

With rapid development infectious lesion or involvement of brain stem structures in the process, it is possible to disrupt vital functions - breathing and cardiac activity. In this case, the patient needs intensive therapy.

Diagnostic measures

Correct diagnosis of neuroinfections is necessary to select effective treatment and prevent their complications. For this purpose, examination of patients with central nervous system lesions is carried out according to the following algorithm:

1. Clarification of all complaints, as well as how long ago they occurred. This is necessary to determine the nature of the course of the disease, as well as to carry out differential diagnosis between pathologies. It is important to clarify with the patient the presence of risk factors - traumatic brain injuries, visits to areas endemic for any infection, contact with patients in infectious diseases hospitals, etc.
2. An external examination allows you to assess consciousness, the degree of its impairment, as well as changes in the skin and mucous membranes. With meningococcal infection, a hemorrhagic rash may be present on the skin. Specific rashes are also present in other diseases - herpes zoster, rubella, etc. Each patient's blood pressure level and heart rate are assessed. During neurological examination it is possible to detect paresis, paralysis, sensory disturbances, stiff neck, etc.
3. Laboratory tests consist of general clinical tests. A clinical blood test against the background of inflammation can detect leukocytosis in case of bacterial infection and lymphocytosis in case of viral neuroinfection. With HIV infection, a decrease in the level of leukocytes is detected. Blood biochemistry shows an increase in acute-phase proteins - fibrinogen and C-reactive protein.
4. The study of cerebrospinal fluid after lumbar puncture is carried out in severe diagnostic cases. Doctors distinguish two specific types of cerebrospinal fluid in the disease - serous and purulent. Purulent changes are characterized by a sharp increase in the number of cells, an increase in protein levels above 1 g/l and a change in the color of the cerebrospinal fluid to cloudy. The serous form is characterized by clear cerebrospinal fluid, a slight increase in the number of cellular elements and protein.
5. Molecular diagnostic tests are used to identify a specific infection affecting the brain. When performing a polymerase chain reaction (PCR), a specialist can detect nucleic acids (DNA or RNA) of the pathogen in the blood or cerebrospinal fluid. Second method - linked immunosorbent assay(ELISA) is aimed at searching for antibodies against proteins of infectious agents. If IgM class antibodies are detected in the blood, then the infection is acute, and if IgG is chronic. In addition to these tests, it is possible to perform a hemagglutination reaction, study the ability of complement to bind, etc.
6. To determine the sensitivity of the pathogen to drugs, microbiological studies are carried out. Bacteria obtained from purulent lesions are placed on special media, which makes it possible to evaluate the effectiveness of antibiotics before they are prescribed.
7. Magnetic and CT scan allow you to assess the state of brain structures and identify their disorders. Brain abscesses and swelling are clearly visible on MRI.

Only the attending physician should interpret the results obtained. Patients with infectious lesions of the central nervous system require hospitalization and prescription complex therapy. Attempts at self-medication lead to the progression of pathology and the development of complications.

Treatment approaches

Therapy is carried out in a medical facility. In severe cases of neuroinfection, patients are placed in the intensive care unit, where they are under constant medical supervision with monitoring of vital functions. Treatment is based on the use of drugs and includes 3 approaches: etiotropic, pathogenetic and symptomatic.

Etiotropic treatment

The use of drugs aimed at eliminating the pathogen is the “gold standard” for the treatment of neuroinfections. If the bacterial nature of the disease is detected, the patient is prescribed antibacterial drugs broad spectrum of action: Amoxiclav, Azithromycin, Cefepime, etc. After bacteriological studies and determining the sensitivity of a particular pathogen, the antibiotic can be changed.

Approved etiotropic therapy is also available for a number of viral infections. For herpetic lesions high efficiency possesses Acyclovir and Ganciclovir. The drugs block the proliferation of viral particles and prevent their penetration into healthy cells. If damage to the central nervous system occurs after influenza, Oseltamivir and its analogues are used in treatment.

When a fungal infection is detected, systemic use of antifungal agents is necessary - Metronidazole, etc. It is important to note that any medications are assigned as a course. It is impossible to interrupt it when the symptoms disappear, as this can lead to the transition of the disease to chronic form and the emergence of drug-insensitive pathogens.

Pathogenetic agents

To prevent the progression of neuroinfections and their complications, various groups of medications are used:

• infusion therapy using crystalloid solutions (isotonic sodium chloride solution, Disol, etc.) is necessary to reduce the severity of intoxication syndrome;
• diuretics (Furosemide) and glucocorticosteroids (Dexamethasone) are used to prevent and eliminate cerebral edema;
• antihistamines (Erius, Loratadine) reduce the degree of sensitization of the body to microorganisms;
• To improve microcirculation and prevent thrombosis in cerebral vessels, Clopidogrel, Aspirin and other antiplatelet agents are used.

At viral infections and identifying protozoa, immunomodulators are prescribed - interferon and its inducers (Amiksin, Polyoxidonium, etc.). Medicines stimulate the activity of the immune system and prevent the progression of central nervous system damage.

Symptomatic approach

An important part of treatment is eliminating clinical manifestations. Most often, patients are prescribed painkillers: Ketorol, Nimesulide, etc. These are drugs related to non-steroidal anti-inflammatory drugs that reduce pain and reduce the severity of inflammation. When the temperature rises above 38.5°C, antipyretic medications are used - Paracetamol, etc.

For vomiting associated with intoxication of the body or increased intracranial pressure, antiemetics are used: Metoclopramide, Ondansetron and Cerucal. Anticonvulsants, primarily valproic acid preparations, are used when febrile or other seizures occur.

If the patient exhibits severe necrosis of certain areas of the brain, its compression or abscesses, surgical treatment is indicated.

Forecast

The prognosis depends on the type of pathology, the state of the immune system, timely detection of the disease and the usefulness of the treatment. If the disease is detected at the initial stages of development and the patient is hospitalized in a medical institution, in most cases it is possible to achieve recovery with minimal risks of complications.

Can a neuroinfection go away on its own?

Unfortunately no. A decrease in the severity of symptoms is associated with the transition of the disease to a chronic form.

When attempting self-treatment or using incorrectly selected therapy, infectious brain lesions quickly progress. In these cases, complications may develop, including disability or death of the patient.

Preventive actions

There are two types of prevention - specific, aimed at preventing infection of the body with a specific pathogen, and nonspecific. For some types of neuroinfections, specific preventive measures, for example, vaccination against polio and herpes viruses.

Nonspecific prevention includes avoiding contact with infected people, treating concomitant diseases, using immunomodulators, etc.

is a generalized name for many infectious diseases of the nervous system. There is a risk of getting sick at any age, but since infections penetrate the body more easily with reduced immunity, children whose the immune system not yet formed.
Neuroinfection in children is a serious disease, since without treatment it can lead to the worst consequences: delayed mental and physical development, dementia, blindness and deafness, paralysis and even death. If a child exhibits any unhealthy manifestations of a nervous nature, and especially against the background of a high temperature, it is necessary to immediately contact the clinic.

Signs of neuroinfection

Diseases caused by neuroinfection are divided into acute, subacute and chronic. The most common conditions are:

• encephalitis, meningitis and myelitis and their forms are the most acute and serious diseases of the brain and spinal cord that require immediate hospitalization;
• radiculitis, neuritis;
• secondary neuroinfections (neurosyphilis, neurobrucellosis, tuberculosis, etc.).

Infection with a neuroinfection occurs through the bites of insect carriers (for example, encephalitis ticks) or infected animals, consumption of milk from such animals, such as complications after acute respiratory infections or ENT diseases of an infectious nature, through direct contact with infected blood and mucous membranes, from mother to child during childbirth.

Symptoms of neuroinfection have varying degrees of manifestation, depending on the severity of the condition:

• For acute form characteristic: heat and general signs of intoxication, headaches, photophobia, convulsions, confusion, speech disorders, impaired coordination of movements, temporary hearing and vision disorders (hallucinations, decreased acuity, blindness or deafness), loss of consciousness and coma;
• chronic infection is rarely accompanied by a temperature rise above 37.2˚C, but headache, frequent nausea, paresis of the limbs, sensory disturbances, depressed consciousness, drowsiness and lethargy, tachycardia with decreased blood pressure, decreased labor and social activity.

It would not be amiss to emphasize once again that neuroinfection is dangerous in itself, but transferred to early age, it threatens severe complications, ranging from disturbances of sensitivity and motor activity, to mental retardation, disability and death.

Diagnosis of neuroinfection

Regarding this disease, you should contact a pediatric neurologist, who will prescribe the following studies:

• magnetic resonance or computed tomography,
• evoked potential study,
• spinal puncture and examination of the cerebrospinal fluid for the presence of infection.

If you suspect a neuroinfection in a child, it is best to contact a specialized neurological clinic. The Aximed Neurology Clinic specializes in the examination and treatment of neurological diseases, and neuroinfections account for 40% of all cases of nervous system diseases. At the Aximed clinic

• employs neurologists, infectious disease specialists and diagnosticians with many years of professional experience,
• diagnostics are carried out using the latest methods and the most modern equipment,
• and in the rehabilitation department you will be met by exercise therapy instructors who, using special simulators, will help you regain freedom of movement.

Treatment of neuroinfection in children

Treatment always depends on the pathogen that caused the disease. After diagnosis, appropriate therapy is prescribed: antiviral, antibacterial, antifungal or antiprotozoal. In addition, symptomatic therapy is carried out: antipyretic drugs, anticonvulsants, sedatives.
One of the main goals of therapeutic measures is to increase immunity. For this purpose, vitamin therapy, hardening procedures and improving the overall physical health of the child are carried out.

In case of serious damage to the nervous system, a course of rehabilitation must be prescribed to restore impaired functions: occupational therapists help to relearn how to dress, eat independently, tie shoelaces, write and perform other daily manipulations, kinesthesiologists restore the ability to move independently and perform large manipulations of the limbs, speech therapists help to restore speech.
Despite the complexity and seriousness of the disease, timely detection and adequate treatment of neuroinfection make it possible to avoid undesirable consequences as if there was no illness at all.

Currently, more than 1,500 pathogens have been identified that can infect the nervous system. Neuroinfections are characterized by particular severity, duration of illness and frequent unfavorable outcomes. The problem of treating patients with infectious diseases of the brain and spinal cord, as well as peripheral nerves is especially acute due to the fact that not all drugs are able to penetrate the nervous tissue.

Classification

Neuroinfections graded according to several criteria. Depending on the timing of penetration of the pathogen into the nervous tissue, these diseases can be:

• lightning fast (development is rapid, within several hours and even minutes);
• acute (increasing symptoms over 1-2 days);
• subacute (smoother onset of the disease with the formation of the main symptoms over a period of several days to a week);
• chronic (long-term, often latent onset of the disease).

If an infectious agent directly caused a neuroinfection, the disease is considered primary. If damage to the nervous system occurs as a result of an already formed infectious focus in any other organ (lungs, bones, liver), they speak of secondary process.

Kinds

The etiological factor determines the classification of neuroinfections into:

• Viral;
• bacterial;
• fungal;
• caused by protozoa.

The main representatives of neuroinfections are:

• Meningitis,
• Encephalitis;
• Myelitis;
• Demyelinating diseases;
• Amyotrophic lateral sclerosis;
• Neurosyphilis;
• Polyneuropathy;
• Shingles.

Pathogenesis

The mechanism of disease development is determined by the form of neuroinfection. Most often, the pathogen enters the central nervous system through the blood, limbus, or perineural spaces. In most cases, the neuron is affected both directly by the infectious agent and by the toxins it secretes.

When affecting the peripheral nervous system, the pathogen initially affects the myelin sheath of the nerve fiber. Long-term severe neuroinfections can subsequently injure the nerve axon.

Symptoms (signs)

The clinical picture of the disease will vary depending on the form of neuroinfection, the main pathogen, and the severity of the process. However, there are a number of characteristic features common to all infections. These signs include general infectious and cerebral syndromes, which manifest themselves:

Neuroinfections that occur with damage to the meninges are manifested by meningeal syndrome (stiff neck muscles, Kernig's sign, Brudzinski's sign). Involvement of the central nervous system in the pathological process will provoke the formation of focal neurological symptoms - paresis, hypesthesia, extrapyramidal syndrome, damage to the cranial nerves, and disorders of higher mental functions.

Damage to the peripheral nerves will manifest itself as increasing flaccid paresis with muscle atrophy, hypoesthesia of the mononeuritic, polyneuritic or radicular types.

Diagnosis and treatment

Due to the severe consequences of neuroinfections, their detection must be rapid and accurate. For this purpose, it is desirable to conduct a set of studies:

Treatment of patients with neuroinfection is carried out taking into account the etiology. Antibacterial, antiviral or antimycotic therapy can be started even before the infectious agent is identified. In these cases, they resort to empirical selection of treatment followed by transfer to drugs that are active against a specific pathogen.

Additionally, in order to minimize intoxication, massive infusion treatment is carried out; when signs of cerebral edema appear, diuretics and glucocorticoids are used. In parallel, neurotrophic therapy is carried out with antioxidants, neurometabolites, vasoactive agents, and nootropics.

Specific treatment is continued until the body is completely cleansed of the infectious agent. However, rehabilitation therapy continues after. Patients who have suffered neuroinfections require mandatory additional rehabilitation measures. These include:

• Medication exposure;
• Physiotherapy;
• Massage;
• Physiotherapy;
• Biofeedback therapy.

Among the above methods, a large place is given to the use of biologically active natural preparations, which allow restoring the functioning of the nervous system in the most physiological natural way. For enhanced nutrition of the cells of the nervous system, the colloidal phytoformula “Brain Booster” can be successfully used. Due to the unique composition of natural neuroactive ingredients, the drug increases the energy supply of neurons. This protects them from the influence of adverse external influences (peroxide oxidation, hypoxia, etc.) and makes the functioning of the nervous system as a whole more efficient. A separate property of the biologically active phytoformula is the ability of “Brain Booster” to improve microcirculation and level out conditions of oxygen deficiency.

It is important to remember that complex rehabilitation treatment of patients after neuroinfections, including the use of the colloidal drug “Brain Booster” should be early, systemic, long-term and regular. It is by following these rules that the effectiveness of the therapy is significantly improved.

Encephalitis, their mixed forms, differing in manifestations and diagnostic capabilities.

The issue of brain infection in children is especially relevant, since in at this age the body is extremely sensitive to various pathogens and can quickly develop Neuroinfections of the brain - serious infectious diseases with damage to the central nervous system and the development of severe symptoms. At the same time, several types of such diseases are distinguished: coma, other life-threatening conditions.

Main causes

The occurrence of any neuroinfection is based on infection of a person and his central nervous system with various microorganisms: bacteria, viruses or fungi. In this case, an infectious process develops, characterized by the development of inflammation and cell damage. In addition, infection can result from:

• , in particular with the phenomenon of long-term compression of brain structures;
• prolonged hypothermia;
• use of non-sterile instruments during surgical procedures on the head;
• a viral infection that can serve as a factor in weakening the immune system.

As a result of the action of such factors, infection of the central nervous system by microorganisms may occur. There are three main types of central nervous system damage:

1. Meningitis - characterized by the development inflammatory process in the meninges.
2. – inflammation and infection are associated with direct damage to brain tissue.
3. Mixed form - elements of meningitis and encephalitis are combined.

Different forms of the disease may differ in their main manifestations, which can be used in diagnosing neuroinfection of the brain and determining treatment tactics.

Symptoms of neuroinfections

Symptoms of brain infections include: common features, and distinctive features. With meningitis, cerebral manifestations come to the fore, such as:

• headache, sometimes accompanied by vomiting;
• a significant rise in the patient’s body temperature to 39–40 o C;
• stiffness of the posterior neck muscles;
• phenomena of general intoxication with muscle pain, weakness and increased fatigue.

With encephalitis, there are practically no individual neurological symptoms, which makes it possible to distinguish it from meningitis. In the latter case, the symptoms of neuroinfection of the brain are predominantly focal:

• headaches of varying intensity;
• disturbances in movement or sensation in the limbs;
• disturbances in eye movements, decreased visual acuity or loss of visual fields;
• various disorders of gait and coordination of movements;
• cognitive impairment (decreased memory, ability to think);
• temperature rise to 38–39 o C.

In this case, the manifestations of meningitis are characterized by individual neurological defects associated with direct damage as a result of inflammation of specific brain regions.

Diagnostic measures

The most important place in the diagnosis of neuroinfections is occupied by an external examination of the patient to determine his neurological status. Already at this stage, the attending physician may suspect the form of the lesion and determine the localization of the pathological process.

However, to clarify the diagnosis and determine the location of the lesion, laboratory and instrumental methods are used:

1. Neuroimaging methods: computer and magnetic resonance imaging, allow you to assess the condition of the tissue of the central nervous system and meninges.
2. Electroencephalography is used to assess the functioning of brain cells and can reveal the extent and severity of damage to nerve tissue.
3. Electroneuromyography is used to determine the severity of damage to the nerve pathways if the patient has paresis or paralysis.
4. Lumbar puncture followed by analysis of cerebrospinal fluid allows us to identify the inflammatory process in the central nervous system and determine its causative agents (viruses or bacteria).
5. Clinical and biochemical blood tests help identify the inflammatory process in the body.

Correct use of the described methods, together with the collection of complaints and a neurological examination, allows you to make the correct diagnosis and prescribe rational treatment.

Treatment of neuroinfection

The main approach to treatment is etiological. Selection required medicine aimed at combating the causative agent of the disease. For this purpose, use or antibacterial agents for bacterial infections, or antiviral for viral neuroinfections.

It is very important to start therapy as early as possible: treatment begins with broad-spectrum drugs, later moving on to medications to which the identified pathogen is sensitive.

In addition, antioxidants (Dihydroquercetin, alpha-tocopherol) can be used to improve metabolic processes in neurons. Patients are prescribed massive infusion therapy(isotonic solutions, Disol, Trisol), glucocorticosteroids, vasoactive drugs (Cerebrolysin, Cavinton).

It is very important to begin rehabilitation measures as early as possible, consisting of the use of:

• medicines (antioxidants, nootropics);
• massage and therapeutic exercises;
• physical therapy.

Early rehabilitation can improve the prognosis for recovery and reduce residual neurological symptoms. Any medications must be selected by the attending physician in a medical hospital setting. Under no circumstances should you engage self-treatment neuroinfections.

Infectious damage to the central nervous system is a serious disease, leading to severe symptoms and possible neurological deficits in the future (paralysis, dementia). If any of the symptoms described above appear, you must immediately seek medical help by self-reporting or calling an ambulance medical care. It is necessary to begin therapeutic measures as early as possible.

– a group of infectious pathologies that are caused by bacteria, viruses, fungi or protozoa, characterized by the predominant localization of the pathogen in the central nervous system and signs of damage to its parts. Clinical manifestations are represented by meningeal, intoxication, liquorodynamic syndromes, and vegetative-vascular disorders. In the diagnostic process, anamnestic data, results of physical, general clinical laboratory, serological, bacteriological or virological studies are used. During treatment, antibiotics are prescribed or antiviral drugs, pathogenetic and symptomatic agents.

ICD-10

G00 G04 G06 A80

General information

Neuroinfections are a relatively common group of pathologies. According to statistics, infectious lesions of the central nervous system reach 40% in the structure of neurological morbidity. The main part is bacterial and viral meningitis, the prevalence of which in different geographical regions ranges from 5-12 cases per 100,000 population per year. Most diseases included in this group are characterized by autumn-winter seasonality. They can be found among everyone age categories population, but the bulk of patients are children under 10-12 years of age and persons who have not received vaccines according to the vaccination schedule.

Causes of neuroinfections

The etiology of infectious damage to the structures of the central nervous system depends on the type of disease. In most episodes, the source of infection is a sick or healthy human carrier. Contributing factors are constant contact with a large number of people, head injury, immunodeficiency states, chronic somatic pathologies, and promiscuous sex life. The following mechanisms of infection are distinguished:

• Airborne. It is realized when coughing, sneezing, talking. Characteristic of pathogens of bacterial and viral meningitis, encephalitis, poliomyelitis, herpes infection.
• Contact and household. It involves the transmission of an infectious agent through direct contact with a patient, carrier or infected household items. This is one of the ways of spreading herpes viruses, polio, and syphilis.
• Fecal-oral. A type of transmission in which the pathogen is excreted in feces and enters the body through food or water. Can be used for herpes infection, ECHO and Coxsackie viruses, botulism, polio.
• Sexual. With this option, infection occurs during sexual intercourse through the mucous membranes of the genital tract. This is how HIV infection, syphilis, and, less commonly, viruses that cause meningitis and encephalitis are spread.

Pathogenesis

Each form of neuroinfection has its own pathogenetic features, but the mechanisms of development of most syndromes and symptoms are usually similar in all variants of this group of diseases. The infectious syndrome is caused by antigen-antibody complexes and pathogen toxins, which have a destructive effect on the central nervous system, causing disturbances in vascular tone, metabolism and hemodynamics in general. Meningeal syndrome develops with inflammatory damage to the meninges and increased intracranial pressure. Autonomic disorders are caused both by direct contact of infectious agents with the centers of the autonomic nervous system, and by indirect effects through intracranial hypertension. Liquorodynamic changes are potentiated by increased production of cerebrospinal fluid against the background of irritation of the choroid plexuses and blockade of pachyonic granulations, complicating the process of its resorption.

Classification

The use of systematization is due to the need to combine a large number of heterogeneous infectious pathologies involving the nervous system. Depending on the nature of the morphological changes, clinical features and the specific pathogen in neurology, several groups of CNS lesions of infectious origin are distinguished. The main types of neuroinfections are:

1. Encephalitis. Diseases with inflammation of brain tissue. The most common are tick-borne, herpetic, chickenpox and rubella encephalitis. Manifestations depend on the type of pathogen and may include cerebral, focal symptoms, systemic intoxication of varying severity.

2. Meningitis. Diseases in which there is damage to the meninges. Characterized by the presence of meningeal and intoxication syndromes, taking into account the characteristics of the inflammatory process, they are divided into:

• Purulent. They are provoked by bacteria, protozoa or fungi, and can be primary or secondary. Primary include meningitis caused by meningococcus, pneumococcus, and Haemophilus influenzae. Secondary lesions are a complication of purulent processes in other localizations - paranasal sinuses, middle ear, etc.
• Serous. Accompanied predominantly by lymphocytic pleocytosis. The causative agents are tuberculosis bacillus, mumps virus, Coxsackie enterovirus and ECHO.

3. Polio. Damage to the central nervous system caused by RNA-containing poliovirus. It can occur in two forms: non-paralytic (meningeal, abortive, inapparant) and paralytic (spinal, pontine, bulbar, encephalitic).

4. Brain abscess. It is an accumulation of purulent masses limited by a capsule in the tissues of the brain. May be of otogenic, rhinogenic, metastatic or post-traumatic origin. It manifests itself as systemic intoxication, focal neurological symptoms, and, less commonly, epileptic and hypertensive syndromes.

5.Shingles. A variant of chronic neuroinfection caused by human herpesvirus type III – Varicella-Zoster. Persistence of the pathogen in the spinal ganglia is observed with activation during decreased immunity or injury. The main symptoms include sharp pain, herpetic eruptions in the area of ​​1-2 dermatomes.

6. Neurosyphilis. Infectious pathology provoked by Treponema pallidum. At the early stage of damage to the central nervous system, general infectious, general cerebral and focal symptoms are observed with dysfunction of the II, III, VI, VIII pairs of cranial nerves. In the later stages, progressive dementia develops, mental disorders and stroke-like symptoms are identified.

7. Botulism. Infection, caused by Clostridium botulinum and accompanied by interruption of transmission nerve impulses at cholinergic synapses. Signs of damage to the motor nuclei of the brain stem and anterior horns are detected.

8. NeuroAIDS. Caused by infection with the human immunodeficiency virus. Often represented by primary lesions of the central nervous system: encephalopathies, recurrent HIV meningitis, vacuolar myelopathy. Manifestations are varied and include paresis, aphasia, ataxia, mnestic disorders, and psychopathological disorders.

Symptoms of neuroinfections

The clinical picture depends on the form of infection of the central nervous system. Combinations of various general clinical manifestations of neuroinfections are usually observed: intoxication, meningeal, vegetative-vascular and liquorodynamic syndromes. The general infectious syndrome is formed several days or hours before the appearance of signs of the acute stage of damage to the nervous system; it can be represented by a moderate headache, malaise, weakness, catarrhal symptoms, an increase in body temperature to 38-39.5 ° C, bowel disorders such as diarrhea or constipation , fluctuations in blood pressure, tachycardia, less often – convulsive readiness, mental disorders.

Meningal syndrome occurs when the meninges are involved in the pathological process and consists of general cerebral symptoms, muscle-tonic and radicular symptoms. The first group includes intense diffuse bursting headache; photophobia, hypersensitivity to sounds and light, vomiting without nausea, which does not bring relief. Often there is a disturbance of consciousness such as hallucinations, delirium, stupor, stupor. Children may experience febrile seizures. Musculo-tonic and radicular manifestations include nuchal rigidity, Kernig's, Brudzinski's, Lessage's, Gordon's, Mendel's, Bekhterev's symptoms, etc.

Autonomic-vascular disorders in neuroinfections can be of a sympathoadrenal, vagoinsular or mixed nature. In the first case, an increase in heart rate, increased blood pressure, excessive sweating and thirst is detected, in the second - bradycardia, arterial hypotension, and excessive urination. In the mixed version, symptoms from different groups are combined with each other. Disruption of normal cerebrospinal fluid circulation can occur in a hypertensive or hypotensive type. More typical of neuroinfections is intracranial hypertension, accompanied by depression of consciousness, convulsive and dislocation syndromes.

Diagnostics

The diagnostic program for CNS infections is based on history, physical examination, general clinical and specific laboratory tests. Radiation diagnostic methods are rarely used, often for the purpose of differentiation from space-occupying lesions of the nervous system. The patient examination program may include the following procedures:

• Finding out your medical history. When communicating with the patient or his relatives, the treating infectious disease specialist or neurologist details the existing complaints and determines the dynamics of their development. An important role is played by epidemiological history - contact with infectious patients or travel abroad over the past 21 days.
• General and neurological status. During the examination, the doctor determines the level of consciousness, examines the skin and mucous membranes to look for rashes, determines the heart rate and arterial pressure. When establishing the neurological status, the specialist assesses the tone of the occipital muscles and identifies specific symptoms characteristic of various neurological syndromes.
• General clinical laboratory tests. IN general analysis blood, in addition to an increase in ESR, the following changes are noted: with a bacterial infection - high neutrophilic leukocytosis, with a viral infection - leukocytosis with a shift in the leukocyte formula to the right, with HIV infection and severe immunodeficiencies - leukopenia. Indicators biochemical analysis blood depend on concomitant lesions of internal organs.
• Spinal tap. With neuroinfections, there are two main variants of changes in the cerebrospinal fluid (protein-cell dissociations) - purulent and serous. In the first type, the spinal fluid is cloudy, has a certain color (white, yellowish), neutrophilic pleocytosis is observed from 1,000, an increase in protein level from 1.0 g/l. In the serous form, the cerebrospinal fluid is transparent, opalescent, and cytological examination lymphocytic pleocytosis of more than 100 is detected, the protein level is above 0.4 g/l.
• Serological study. Is in the definition higher level antibodies in the blood using hemagglutination suppression, complement fixation or neutralization reactions. ELISA is used, during which specific IgM to the pathogen is detected. PCR is performed to clarify the DNA or RNA of the infectious agent.
• Virological or bacteriological diagnostics. It involves determining the causative agent of the disease in the patient’s blood or cerebrospinal fluid by inoculating samples on specific nutrient media. After identifying the pathogenic agent, it is advisable to clarify sensitivity to the main antibacterial drugs.

Treatment of neuroinfections

All neuroinfections are an indication for hospitalization of the patient in an infectious diseases or neurological hospital. In severe condition and the need for continuous monitoring of vital functions (breathing, heartbeat), the patient is transported to the ICU. The treatment program includes the following activities:

1. Etiotropic therapy. The main goal is to eliminate the pathogen from the patient's body. First, broad-spectrum drugs are used. After receiving the results of serological and bacteriological research medications are replaced with antibacterial or antiviral agents, to which the identified pathogen showed the greatest sensitivity.
2. Pathogenetic drugs. They are used to combat systemic intoxication, cerebral edema and homeostasis disorders, to correct water and electrolyte balance, desensitization and stimulation of the immune system. Plasma substitutes, diuretics, glucocorticosteroids, antihistamines, interferons, donor and artificial immunoglobulins, and anticoagulants are prescribed.
3. Symptomatic remedies. This category includes medications that relieve individual symptoms and improve the general condition of the patient: analgesics, antipyretics, antiemetics, anticonvulsants, antipsychotics.
4. Surgery. The nature of the surgical intervention depends on the changes detected. Surgery may be required in the case of an abscess, brain tuberculoma, spinal cord compression in tuberculous spondylitis, large areas of necrosis in herpes zoster.

Prognosis and prevention

The outcome of neuroinfection is determined by the type of disease, general condition patient, timeliness and completeness of treatment. In most cases, a timely diagnosis and adequate therapy can save the patient’s life and minimize the risk of complications. In some forms of neuroinfections, for example, encephalitis, mortality reaches 50-80%. Specific prevention is represented by vaccines against specific pathogens: herpes viruses, botulism, tick-borne encephalitis, measles, polio, meningococcus, etc. Nonspecific preventive measures are aimed at strengthening the immune system, timely treatment immunodeficiency states and preventing contact with potential carriers of infectious diseases.