Diagnosis Of Toxoplasmosis In Humans And Animals, Pregnant

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• Principles of diagnosing toxoplasmosis
• The first stage of diagnosis - examination of the patient
• Serological diagnostic methods
• Interpretation of the analysis by ELISA
• Allergic diagnostic method
• Parasitological method for the diagnosis of toxoplasmosis
• Instrumental diagnostics for toxoplasmosis
• Instrumental diagnosis of toxoplasmosis
• Differential diagnosis of toxoplasmosis
• Symptoms of congenital toxoplasmosis
• Acquired toxoplasmosis symptoms
• You can defeat parasites!

Toxoplasmosis is an infectious disease that affects humans and some warm-blooded animals. Representatives of the feline family are considered the main vectors.

The disease is caused by microscopic parasitic microorganisms. This disease is very often accompanied by damage to the nervous system, an unnatural increase in the size of the spleen, liver, lymph nodes.

What to do in such a situation? To get started, we recommend reading this article. This article details the methods of dealing with parasites. We also recommend contacting a specialist. Read the article >>>

Despite this, toxoplasmosis is not terrible for an ordinary person. It is asymptomatic and does not cause any negative consequences. The most severe complications from toxoplasmosis are observed with intrauterine infection or in individuals with reduced immunity.

Toxoplasma gondii

Principles of diagnosing toxoplasmosis

If a diagnosis of toxoplasmosis is suspected, it should be differentiated from other diseases that occur with similar symptoms. First of all, these include:

• Infectious mononucleosis;
• tuberculosis;
• lymphoreticulosis;
• chlamydia;
• oncological and many other diseases.

Epidemiological factors are also of little importance in making the correct diagnosis. These include close contact with cats, dietary habits, lifestyle, profession, etc. These factors are of relative value during diagnosis, since almost anyone can get sick.

A feature of the disease is that it is characterized by a variety of clinical manifestations, but the complete absence of symptoms characteristic only of it.

The first stage of diagnosis - examination of the patient

When examining a patient during an acute course of toxoplasmosis, one can find:

• increased body temperature, but it rarely rises more than subfebrile indicators;
• significant increase in the size of the liver and spleen. In this case, these organs become quite painful on palpation;
• an increase in the size of the lymph nodes. Usually their diameter reaches 1-1.5 cm. Lymph nodes are soft to the touch and painful. They usually do not connect to adjacent tissues;
• in the general analysis of blood, some changes are also observed.

Serological diagnostic methods

To determine antibodies to toxoplasmosis, the following diagnostic methods are used:

1. RIF, or immunofluorescent reaction, is carried out in this way: with the help of special chemical reagents, the material is diluted. Antibodies will be visible in a special microscope that displays ultraviolet light. In the presence of toxoplasmosis, the glow will be bright - this result is displayed as: +++ or ++++.
2. RNG, or the indirect hemagglutination reaction, is based on the property of erythrocytes to precipitate during certain chemical reactions. If, after carrying out the necessary laboratory manipulations, the erythrocytes have covered the bottom of the tube, the result is positive. It is designated as follows: "intense reaction +++" and "sharply intense reaction ++++".
3. ELISA, or the method of immunoassay diagnostics, is used to determine toxoplasmosis more often than others, since it has a number of advantages: it is carried out quickly, using special equipment, it has the ability to trace the dynamics, and also to analyze 2 types of immunoglobulins IgG and IgM. To carry out such an analysis, test systems manufactured in the Czech Republic and Finland are used. Such tests can be successfully carried out for all groups of subjects, including HIV-infected people.

Interpretation of the analysis by ELISA

In order to correctly decipher the results of the analysis by the ELISA method, one should understand the essence of the biological processes of infection. Antibodies of the protein groups of immunoglobulins of the type IgG and IgM are produced by the body to fight the pathogen and protect against secondary infection.

IgM antibodies are produced by the body immediately after infection with toxoplasmosis, are in the body for up to a month, after which the indicators gradually decrease and completely disappear. Thus, the detection of antibodies of the IgM group in the analysis is a sign of the acute form.

Immunoglobulins of the IgG type begin to be produced in the body on the 3rd day of infection and protect a person from re-infection with toxoplasmosis throughout life.

Thus, the detection of antibodies of this group and the absence of IgM indicators indicate that the body is protected, therefore there is no cause for concern.

But there are other options for the results of analysis by ELISA. Then the decoding of the analysis for toxoplasmosis requires additional examinations to confirm the acute form of the disease or its absence. The options indicated in the table are possible.

Interpretation of the results of the analysis by the ELISA method:

IgM IgG Designation negative negative There is a risk of infection, since the body has not previously been infected with toxoplasmosis parasites. negative positive Most likely, the infection occurred a long time ago and at the moment there is no danger. But to confirm the result, the doctor will recommend additional studies. positive negative The disease is acute, there was a primary infection. positive positive The infection occurred less than a month ago.

Analyzing the table, it can be noted that it can be difficult to identify acute toxoplasmosis. IgG positive - the interpretation of the analysis can speak of both a previous infection and a primary infection. But the presence of IgM antibodies usually indicates an acute stage of the disease.

Allergic diagnostic method

An allergic method for diagnosing toxoplasmosis allows you to identify the presence of these pathogens in the human body by monitoring the body's immunological response. In this case, the patient is injected intradermally with a special drug - toxoplasmin.

It is an antigenic complex that is obtained by taking intra-abdominal fluid from white mice that suffer from toxoplasmosis. This drug is injected externally into the shoulder in an amount of 0.1 ml.

When conducting an allergic test, the development of hyperemia or redness of the skin near the injection site is taken into account. They can also observe the accumulation of the injected substance in the tissues (infiltration).

When conducting an allergy test, the following reactions can be observed:

• sharply positive. It is characterized by the size of the intradermal reaction, which exceeds 20 mm;
• positive. A pronounced reaction is observed, the size of which is from 13 to 20 mm;
• weakly positive. It is characterized by the size of the intradermal reaction from 10 to 13 mm;
• negative. The size of the intradermal reaction after administration of the drug does not exceed 9 mm.

A positive reaction always indicates the presence of a disease in the human body, and a negative one confirms its absence in any form (acute or chronic).

Parasitological method for the diagnosis of toxoplasmosis

A parasitological diagnostic method is possible because toxoplasmosis is caused by microscopic parasitic microorganisms. In a sick person, they can be easily identified using certain research methods.

For example, Toxoplasma is very often found in blood, cerebrospinal fluid, amniotic fluid, etc. They can also be found in some tissues. This method of diagnosing toxoplasmosis is very often used when performing a biopsy of the lymph node.

Instrumental diagnostics for toxoplasmosis

Toxoplasmosis is a disease that can affect many organs and systems in the human body. Therefore, when it is detected or only if there is a suspicion of the presence of this problem, an extensive instrumental examination is performed.

It is aimed at identifying many pathologies that were triggered by the activity of parasitic microorganisms.

For this, the following methods of instrumental diagnostics are used:

• electrocardiogram. Allows you to identify problems in the work of the heart;
• ultrasound procedure. Most often it is produced for organs located in the abdominal cavity - liver, spleen, pancreas;
• x-ray. It is produced in order to identify pathological changes in the lungs, soft tissues;
• perimetry, refractometry and other diagnostic methods to determine the condition of the eyes.

Instrumental diagnosis of toxoplasmosis

When diagnosing cerebral toxoplasmosis (especially in AIDS patients), CT, MRI of the brain are performed: IgG (less often IgM) titers are determined in blood serum and cerebrospinal fluid, the pathogen's DNA is detected by PCR and the pathogen is isolated from them.

Differential diagnosis of toxoplasmosis

Toxoplasmosis is differentiated from many diseases of an infectious and non-infectious nature: lymphogranulomatosis, lymphocytic leukemia and other pathologies of the blood system, tuberculosis, listeriosis, yersiniosis, infectious mononucleosis. diseases of the nervous system and organs of vision.

In children, taking into account age, differential diagnosis of toxoplasmosis is carried out with CMVI, herpetic infections and various acute respiratory viral infections, rubella, viral hepatitis.

In case of repeated miscarriages, the birth of children with developmental anomalies in seropositive women, it is necessary to exclude obstetric and gynecological pathology.

Symptoms of congenital toxoplasmosis

The congenital form of the disease occurs in the fetus when a woman becomes infected with toxoplasmosis during pregnancy.

Depending on the duration of pregnancy, congenital toxoplasmosis can be roughly divided into two groups:

• early congenital toxoplasmosis, in which infection of the mother, and as a result of the fetus, occurs in the first months of pregnancy;
• late congenital toxoplasmosis, in which a pregnant woman becomes infected with toxoplasmosis and transmits the disease to the fetus in the second half of pregnancy.

Often, early congenital toxoplasmosis leads to fetal death, in the form of spontaneous abortion or stillbirth.

That is why, if a woman has contracted this disease, being in a position, the board of doctors (which includes obstetricians-gynecologists and infectious disease specialists) usually decides on the advisability of further preserving the pregnancy.

With late congenital toxoplasmosis, a baby may be born with signs of generalized toxoplasmosis (eg, an enlarged liver, spleen).

There are the following forms of congenital toxoplasmosis:

• acute form;
• chronic form.

Symptoms of the acute form of congenital toxoplasmosis Symptoms of the chronic form of congenital toxoplasmosis

• pronounced signs of intoxication;
• fever;
• enlarged liver and spleen;
• yellowness of the skin;
• maculopapular rash in the form of papules of purple, flesh or dark burgundy color, affecting mainly the trunk, face and limbs;
• headache;
• inflammatory lesions of the eyes;
• encephalitis.

• hydrocephalus - the accumulation of fluid in the brain, leading to deformation of the skull and pathological disorders of the organs of hearing and vision;
• mental retardation, which is manifested by mental retardation;
• chorioretinitis (inflammation of the choroid);
• epilepsy, which is manifested by frequent seizures;
• atrophy of the optic nerves;
• as a complication, blindness and progressive brain damage are possible, the latter often leads to the death of the patient.

Acquired toxoplasmosis symptoms

The following periods of the disease are distinguished:

• incubation period;
• prodromal period;
• the peak period;
• period of convalescence.

Disease period Period duration Period description Incubation period from three days to two weeks It is characterized by the multiplication of pathogens and the accumulation of toxins. This period lasts from the moment the microorganism enters the body until the first symptoms appear. Prodromal period within one to two weeks It is characterized by the appearance of the first non-specific clinical symptoms (for example, fever, malaise, swollen lymph nodes). This period can begin acutely or gradually. The peak period two to three weeks There is a decrease in the nonspecific symptoms of the disease. Also, the vital activity of the body's immune cells is suppressed, which subsequently leads to the development of pathological conditions of the cardiovascular, musculoskeletal and nervous systems. Convalescence period in the third - fourth week of the disease, there is a gradual disappearance of all clinical symptoms It is characterized by the disappearance of signs of the disease and the onset of persistent immunity, which is developed for life.