Toxoplasmosis: Symptoms and Treatment
- Causes of Toxoplasmosis
- Sources of infection
- Symptoms of toxoplasmosis
- Forms of toxoplasmosis and features of their course
- Toxoplasmosis, pregnancy and breastfeeding
- Toxoplasmosis in HIV-infected
- Diagnosis of toxoplasmosis
- Treatment of toxoplasmosis
- Toxoplasmosis Prevention
Toxoplasmosis is a congenital or acquired disease of a parasitic nature, affecting the nervous system, organs of the reticuloendothelial system, the visual apparatus, skeletal muscle and myocardium.
To this day, this parasitic invasion does not lose its relevance and every year, according to the WHO, tens of thousands of people become infected with it. Extremely frequent registration of the disease is associated with the fact that the pathogen of toxoplasmosis is distributed almost everywhere, and every year the risk of infection increases by 0.5-1%.
In the case when a small amount of the pathogen enters the body of a healthy person, it does not represent a great danger, since it is covered with a dense shell and turns into a cyst. According to expert estimates, about half a billion people around the globe have antibodies to the causative agent of this disease.
Most often, toxoplasmosis is diagnosed in regions with a warm climate, and this disease is also characteristic of certain occupational groups (often people who work with raw meat become infected). It should also be noted that the infection of women is 2-3 times higher than that of men.
Unfortunately, due to the lack of compulsory registration and difficulties in diagnosis, it is very difficult to judge the real incidence of infection, as it occurs almost everywhere in the form of sporadic diseases and asymptomatic parasites.
Causes of Toxoplasmosis
The causative agent of the disease is Toxoplasma (Toxoplasma gondi) belonging to the protozoa type (Protozoa), the class of disputes, coccidia order. It was first discovered in Africa in 1908 in spleen mononuclear cells and the liver of a North African gondi rodent. Under the lens of the microscope, Toxoplasma looks like a crescent moon, or an orange slice (toxon in Greek means “arch”).
This unicellular parasite has a rather complex development cycle. Its main owner are cats. It is in their body that the pathogen turns into a mature individual. Infection of the cat occurs when eating raw meat of infected animals, pigeons or rodents. Getting to the intestines of the animal, Toxoplasma begins to multiply and stand out along with the feces into the environment.
The person becomes infected by contact with feline feces, and is considered the intermediate host of the parasite. Penetrating into the human body, Toxoplasma can freely circulate in the blood, infiltrate the regional lymph nodes, deposit in the brain, eyes and muscles, destroy cells and form cavities (cysts and pseudocysts). However, after the death of the parasite, calcinates (dead Toxoplasma saturated with calcium salts) may form in the human body.
In nature, there are several strains of the pathogen. The RH strain is highly virulent and leads very quickly to the death of laboratory animals, and avirulent strains, as a rule, do not cause any clinical manifestations of the disease.
Sources of infection
1. Domestic and stray cats are considered to be the main sources of infection, since the full parasite (tissue and intestinal) development takes place in the body of these animals. Feline feces can persist for a very long time in the external environment, representing a potential danger to other animals and humans, but more often infection can occur when cleaning the cat's toilet.
2. Sand or earth. Very often, Toxoplasma enters the human body through contaminated sand or earth (in the garden, in the garden, in the park, or in the playground equipped with a sandbox).
3. Meat and eggs. Some farm animals and birds are considered intermediate hosts of the parasite. It should be noted that they are not a direct source of infection, since Toxoplasma does not form a cyst in their bodies, but, at the same time, the pathogen can be found in meat (most often in lamb and pork), as well as in bird eggs. In this case, the infection occurs due to insufficient heat treatment of the above listed foods.
4. Unwashed vegetables and fruits. If the food is contaminated with infected land, the risk of infection is simply enormous (from literary sources it is known that a cat in 2-3 weeks can release into the external environment about 2 billion cysts that remain infectious for up to two years).
5. Transmission of infection from mother to fetus. This way of transmitting toxoplasmosis is the most dangerous. Typically, this infection occurs when the parasite enters the body of a previously non-infected woman, and then, through the placenta, into the fetus. In this case, the consequences for the unborn child can be the most catastrophic, and therefore, toxoplasmosis during pregnancy is often an indication for its artificial interruption.
Зараженный токсоплазмозом человек не опасен для окружающих, то есть, прямого заражения от человека к человеку не происходит ни при каких контактах. Note: A person infected with toxoplasmosis is not dangerous to others, that is, direct infection from person to person does not occur under any contacts. However, blood transfusion from an infected donor to a recipient or an organ transplant represents a certain danger, but even in this case, according to experts, the risk of infection is negligible.
Ways of transmission:
- Oral, or alimentary (through the mouth);
- Percutaneous (very rare transmission path);
Symptoms of toxoplasmosis
In the acute stage, the disease affects almost all systems and organs of the body. Patients complain of weakness, drowsiness, chills, and fever. Yellowing of the sclera and skin can be noted, the spleen and liver are enlarged, and a plentiful rash appears. Often, reduced muscle tone and strabismus appears.
If the inflammatory process develops gradually, there is a less pronounced clinical picture. At the same time, changes are observed on the part of the visual apparatus (clouding of the crystalline lens), and also, the brain drops is developing step by step.
For the chronic form of the disease is characterized by irreversible changes in the central nervous system (mental development and complete blindness). Often, with involvement in the pathological process of the central nervous system, patients experience emotional lability, irritability, and even neurasthenic seizures. In women, the menstrual cycle is disturbed, in men, erectile dysfunction or complete impotence can develop.
Forms of toxoplasmosis and features of their course
Depending on the clinical syndrome in medical practice, there are glandular (lymphoganglial), typhoid (exanthematic), visceral, meningoencephalitic (cerebral) and ocular forms of the disease.
Hypertrophy of the lymph nodes (they remain painless), headache, fever, disruption of the autonomic nervous system, damage to the liver, spleen and biliary tract are characteristic of the glandular (lympho-ganglion) form.
The typhoid (exantmatous) form is characterized by an acute onset with fever, chills, headaches, and muscle and joint pain. For 4-7 days from the onset of the disease on the body appears abundant maculo-papular rash. It spreads throughout the body, with the exception of the plantar area and the palms. Lymph nodes, liver and spleen are enlarged, organs of vision and central nervous system are affected. This form of toxoplasmosis is very difficult and often fatal.
The visceral form arises due to the generalization of the parasites by the hematogenous route and the damage of various organs by them. In this case, patients may be diagnosed with interstitial pneumonia, hepatitis, myocarditis, and other severe heart damage.
Cerebrospinal forms are characterized by signs of acute meningoencephalitis, and symptoms depend on the prevalence of inflammation in the brain. In this case, the temperature also rises and sometimes there is a characteristic rash, as well as meningeal symptoms and severe intoxication.
Patients may develop paralysis, paresis, psychosis, loss of hearing and vision, and death is possible.
In acute ocular form of toxoplasmosis, lesions of the visual apparatus manifest as iridocyclitis, choreoretinitis, exudative or serous retinitis and vitreous opacities.
The signs of chronic intoxication are characteristic of this form of the disease. There is a lesion of the reticuloendothelial, nervous and cardiovascular systems, the musculoskeletal system, the digestive tract, and also the organs of vision.
в период обострения патологического процесса наблюдается кратковременная паразитемия (присутствие возбудителя в периферической крови). Note: during the exacerbation of the pathological process there is a short-term parasitemia (presence of the pathogen in the peripheral blood).
This form can be characterized by various clinical manifestations and severity of the course. The disease occurs in both acute and chronic forms with exacerbations and remissions. At the same time various internal organs, organs of vision and hearing and the central nervous system are involved in the inflammatory process.
This form is a consequence of intrauterine infection of the fetus. In the case when transplacental transmission of the pathogen from mother to child occurs in the first trimester of pregnancy, often the fetus dies. If he stays alive, he will usually have severe CNS damage, such as hydrocephalus, acrania, anencephaly, microcephaly, etc.
At a later intrauterine infection, signs of hydrocephalus, meningoencephalitis and choreoretinitis are diagnosed in the newborn.
Toxoplasmosis, pregnancy and breastfeeding
In the event that the infection of the expectant mother occurred more than 6 months before the onset of pregnancy, the infection is not transmitted to the child. With a smaller period of time there is a risk of infection of the fetus, although, according to experts, it is insignificant.
It is possible to talk about intrauterine infection with toxoplasmosis when the causative agent itself or its antibodies are detected in the blood of a pregnant woman, as well as when parasites are detected in the internal organs of the mother and amniotic fluid. If you suspect a primary infection with Toxoplasmosis, consultation of the infectious disease specialist is required and the subsequent analysis is repeated after 2-3 weeks.
Only when the diagnosis is confirmed can a specific treatment be carried out, reducing the risk of a congenital infection. However, this kind of therapy does not completely exclude negative consequences, and therefore, more often than not, doctors recommend abortion.
If toxoplasmosis is detected in the second and third trimester of pregnancy, the woman is prescribed etiotropic therapy and in parallel the study of amniotic fluid is being conducted.
характерно то, что ребенок с врожденным токсоплазмом у одной и той же женщины рождается только один раз, а все её последующие беременности протекают нормально и оканчиваются рождением здорового малыша. Note: It is characteristic that a child with congenital toxoplasma is born to the same woman only once, and all her subsequent pregnancies proceed normally and end with the birth of a healthy baby.
If, during the period of breastfeeding, the nursing mother does not detect active forms of toxoplasmosis, infection through breast milk is practically excluded. However, if there are erosions or bleeding cracks on the nipples in the acute (active) stage of the disease, in which the pathogen is in peripheral blood, the child may become infected. In all other situations, when only signs of a previous illness are detected in maternal blood, you can breastfeed without any fear.
Toxoplasmosis in HIV-infected
Very often, toxoplasmosis develops on the background of a weakened immunity, and therefore it can be found in HIV-infected patients and persons undergoing immunosuppressive therapy. As a rule, such predisposition is associated with the activation of a latent infection. According to statistics, in 95% of cases the cerebrospinal form of toxoplasmosis is detected in HIV-infected patients.
The symptomatology of acute toxoplasmosis on the background of human immunodeficiency is mainly due to CNS damage. The majority of patients suffer from the brain, and, both focal and cerebral clinical signs of the disease can be observed. In 75% of patients, there are mental disorders, in 33% of epileptic seizures, and in 10-72% of cases, fever and headache.
The pathogen, penetrating into the brain, causes necrosis of the brain tissue, and also provokes the development of such secondary pathologies as hemorrhage, edema, or vasculitis . Often, the disease is characterized by a gradual onset, when the symptoms increase over several weeks. However, there are cases when toxoplasmosis begins acutely, with sudden confusion, local headache and fulminant development of focal symptoms (loss of visual fields, hemiparesis, hemiplegia, partial epileptic seizures). In this case, the brain stem, pituitary, basal nuclei and the boundary between the white matter and the cortex are most often affected.
Diagnosis of toxoplasmosis
When making a diagnosis, first of all, it turns out the nature of the flow of the infectious process (carrier or disease).
Due to the huge variety of clinical forms of the disease, its differential diagnosis is much more complicated. Therefore, in the case of an unclear clinical picture, the patient must be prescribed a study for the presence of the pathogen in the body.
For this purpose, a serological method of research is used in laboratory practice, based on the application of the reaction of binding a compliment with the special dye of Sabin-Feldman. When a negative result is obtained, toxoplasmosis is excluded, and when a positive result is obtained, the diagnosis can only be confirmed if there are clinical symptoms.
However, when making a diagnosis, an intradermal test using toxoplasmin, an indirect hemagglutination reaction, an immunofluorescence method and a neutrophilic leukocyte damage reaction can be used.
Absolute confirmation of the diagnosis is in vivo and postmortem parasitological study. It involves the isolation of the causative agent of toxoplasmosis from various biological fluids of the body.
Treatment of toxoplasmosis
Toxoplasmosis is a parasitic infection that does not always need treatment. Unfortunately, it is not possible to completely destroy the pathogen, so a small amount of the parasite and its antibodies remain in the human body until the end of its life.
However, in clinical practice, there were isolated cases where patients were completely cured of the disease. However, this happened only when they were prescribed adequate therapy in the very first days after infection.
After a very small amount of time has elapsed after the pathogen has entered the host organism, Toxoplasma forms cysts that are highly resistant, including to drugs. That is why, when antibodies to the parasite are found in the human body in the absence of clinical signs of disease, treatment of toxoplasmosis is usually not carried out. The exceptions are pregnant women, newborns and people with immunodeficiency.
Drug therapy for the acute form of the disease involves the use of antibacterial drugs and pharmaceuticals of chemical origin (chemotherapy). It should be noted that their use reduces the patient's immunity, which often leads to an exacerbation of the disease. That is why the treatment of toxoplasmosis should be directed not at the complete destruction of the parasite, but at preventing the development of a severe course, accompanied by damage to the internal organs. As a rule, it is prescribed for a pronounced clinical picture of the disease, damage to the central nervous system, lungs, heart and other vital organs.
It should be emphasized that the treatment of toxoplasmosis is a complex and lengthy process, conducted in several courses with the use of etiotropic agents and antibiotics.
Patients with the chronic form of toxoplasmosis in the acute stage are given a week-long course of chemotherapy, and desensitization is also carried out in parallel with the use of corticosteroids and antihistamines. В завершении рекомендован курс иммуномодулирующей терапии, способствующий налаживанию иммунного ответа организма.
Профилактика заболевания заключается в неукоснительном соблюдении правил личной и общественной гигиены. Беременным женщинам не рекомендуется контактировать с кошками, а еще, по возможности не следует допускать животных в песочницы и другие места, где играют дети. Категорически недопустимо дегустировать сырой фарш и употреблять термически необработанное мясо, а также пить сырые яйца и молоко.