Brain toxoplasmosis is understood as an infectious disease that develops when infected with the simplest parasitic microorganisms toxoplasma gondii. An ailment proceeds, as a rule, in a latent form, practically without manifesting itself with external symptoms. In patients with immune disorders, the pathology develops in a different way - they often become infected with brain parasites. Toxoplasmosis of the brain is a serious ailment in which severe damage to the central nervous system occurs.
The causative agent of this pathology
The causative agent of toxoplasmosis of the brain are unicellular parasitic organisms toxoplasma gondii. The structure of such microorganisms is very primitive, but they perfectly adapt to a variety of living conditions.
Toxoplasma gondii is able to parasitize in the body of many species of mammals, birds. Other species are transitional hosts.
The appearance of the parasite can be examined under a microscope - they resemble an orange slice. The development of the microorganism takes place in 2 stages. The first is sexual reproduction, which can take place in the body of cats (domestic, wild). They are the primary hosts of the parasite.
The second stage - asexual - takes place in the body of an animal or bird, where the microorganism is introduced into the structure of cells. The parasite divides until the cell breaks. As a result, the toxoplasma gondii population emerges.
The parasites formed in this way are called tachyzoites. They have the possibility of further reproduction by division, however, the human immune system of a person with normal health easily recognizes and destroys them.
Causes of Human Infection
Between people, toxoplasmosis of the brain cannot be transmitted, except in cases where the transmission occurs from a pregnant woman to her fetus and during an organ transplant. Infection can occur from representatives of the cat family and when eating raw or poorly cooked (fried) meat.
Cats are the only animals in the body of which the parasite is able to form spores - oocysts, whose role is to infect intermediate hosts.
Toxoplasma spores can exist for a long time in environmental conditions, since they are covered with a fairly dense tread sheath. Any animal, bird, when an oocyst is swallowed, becomes its intermediate host, and theoretically it can become a victim and be eaten by a representative of the cat family. In this case, the parasite gets the opportunity to switch to sexual reproduction - the cycle begins to repeat.
The source of infection can also be a domestic cat, which never leaves the premises. This is due to the fact that people can bring a parasite on shoes, feed the animal with unprepared meat. In feline toxoplasmosis occurs without external manifestations, so the owners may not even notice that the animal is infected with a parasite.
Symptoms with this pathology
When infected with brain toxoplasmosis, the period of incubation of parasites takes 2 weeks. After this, the first signs of the disease begin to develop.
If a person has normal immunity, then clinical symptoms will not occur. An infected person may not even notice that he has suffered a disease. In a subsequent blood test, the presence of antibodies to the parasitic organism can be detected.
Acute toxoplasmosis can develop in only 0.2% of patients. Statistics report that half of all cases of the development of the acute form of toxoplasmosis has a cerebral form. Cerebral toxoplasmosis is able to develop only in patients who have disorders in the immune system.
In people without an immune deficiency, cerebral toxoplasmosis of the brain develops only in exceptional cases. For example, in India, only 15 cases of infection with cerebral toxoplasmosis of people with normal immunity over 10 years have been described. In each case described, the disease developed due to malnutrition.
Toxoplasmosis is manifested by characteristic symptoms of encephalitis, meningoencephalitis. In addition, there are frequent cases of the appearance of volumetric formations in the brain.
Symptoms indicating toxoplasmosis of the brain are as follows:
- Visual impairment associated with negative changes in retinal tissues.
- Partial or complete inability to perceive and interpret other people's speech.
- Disorders of a mental nature.
- Epileptic seizures.
- Fever.
How does this ailment begin?
Cerebral toxoplasmosis begins suddenly. The patient has a sharp increase in temperature, there is confusion, an epileptic seizure, and visual impairment occurs. In addition, paralysis of half the body or one limb may occur. Along with this, coordination of movements, speech, swallowing is disturbed.
Patients with symptoms of toxoplasmosis of the brain must be hospitalized in the neurological department of the hospital.
Diagnosis of cerebral toxoplasmosis
The provoked disorders can be diagnosed using MRI, computed tomography.
Compared with MRI of toxoplasmosis of the brain with CT, the dose of contrast medium should be doubled. Both diagnostic methods allow you to establish a diagnosis, and the accuracy will reach 80%.
Serological examination
The most accurate diagnostic method is considered to be a serological examination. In this case, blood samples are checked for the presence of antibodies to parasites. Serological examination allows you to get accuracy up to 97%. In patients infected with AIDS, IgM antibodies are often absent, and therefore the disease is diagnosed in the presence of IgG antibodies.
Risks for HIV-infected patients with this disease
Cerebral toxoplasmosis ranks second in the ranking of opportunistic infections. Such infections include transmitted diseases that almost never develop in people with normal immunity. However, they are deadly for patients infected with AIDS and having poor immunity.
In HIV-infected patients, toxoplasma gondii is capable of affecting absolutely any tissue and organs, but, as a rule, its target is the brain. In 60% of patients with cerebral toxoplasmosis, the formation of volume formations in the central nervous system is observed, approximately 28% suffer from epileptic seizures.
On average, 20% of those infected with HIV are infected with cerebral toxoplasmosis. In AIDS-infected people, encephalitis of toxoplasmosis occurs in 12% of cases.
CNS toxoplasmosis is manifested by the development of fever, headache, mental, neurological pathologies. In HIV patients, toxoplasmosis encephalitis is often accompanied by inflammatory processes in the choroid and retina.
How is the treatment of cerebral toxoplasmosis
For the treatment of cerebral toxoplasmosis, the use of oral forms of antimicrobial drugs, for example, Sulfadiazine, Pyrimethamine, in various combinations is indicated.
Along with the use of Sulfadiazinin, allergic reactions often develop, and therefore it is recommended to supplement the therapy with oral and intravenous use of Clindamycin. Many doctors are sure that this medicine should not be used, since all its benefits are offset by the emerging negative manifestations.
During therapy with “Pyrimethamine”, doctors often change the duration of the course and dose. For example, on the first day of therapy it is indicated to take 200 mg of the drug, and on the following days, it is necessary to calculate the dose based on weight - up to 75 mg / kg. In some cases, Pyrimethamine therapy is the only option.
Against the background of the use of Pyrimethamine and sulfonamides, the production of the enzyme is blocked, under the influence of which folic acid is converted into folinate. In this regard, the therapy of toxoplasmosis must be supplemented with the use of calcium folinate. Undoubtedly, folic acid is a cheaper drug, but its effectiveness is much lower, since the main drug does not allow it to turn into folate and digest.
An alternative to the combination of drugs "Sulfadiazine" + "Pyrimethamine" is a combination of "Sulfamethoxazole" + "Trimethoprim", which shows high efficiency.
If the patient has an allergic reaction to Clindamycin and Sulfadiazine, he is recommended to use Pyrimethamine and Atovaquone, or Pyrimethamine in combination with Azithromycin.
Positive dynamics in this pathology
In the treatment of toxoplasmosis of the brain with the use of these medicines, positive dynamics are observed daily. The patient is prescribed after two weeks of therapy. As a rule, by this moment only insignificant physiological and mental manifestations of the disease remain, which subsequently completely disappear. After a few months, the patient may return to work.
The prognosis of toxoplasmosis of the brain
When a disease is detected at an early stage of development, therapy is successful in almost all cases. In advanced forms, toxoplasmosis is incurable, but constant therapy allows you to stop its manifestations. Lack of therapy can be fatal. In addition, this can provoke the development of the consequences of toxoplasmosis of the brain in the form of hemiparesis, ataxia, aphasia, and severe mental illness.
In this regard, it is important to consult a doctor if the first signs of this disease are detected, because the initial stages of the disease are successfully treated. The main thing is to follow all the recommendations.