Toxocariasis is a disease that, despite its wide spread, practitioners do not know much. Symptoms of the disease are very diverse, so experts from various fields can come across it: pediatricians, hematologists, therapists, oculists, neuropathologists, gastroenterologists, dermatologists and many others.
Toxocariasis in children is much more common than in adults. Usually children are infected at the age of ten to fourteen. It is noteworthy that most of the cases live in rural areas. In general, the disease responds well to therapy, but with damage to vital organs, a fatal outcome is also possible. And what is this ailment, what are its causes and symptoms? This we will try to find out. So, the subject of our conversation: toxocariasis - symptoms, treatment and prevention of the disease.
Pathology Features
Toxocariasis in children occurs as a result of damage to the body by toxocaras - parasitic worms. These are helminths atypical for humans, although in their properties they are largely similar to roundworms. Two types of pathology are distinguished depending on the pathogen that has entered the body. How does one or another toxocariasis manifest itself? Symptoms, treatment of both one and the other species will be the same. So, the disease can be caused by toxocara parasitic in dogs, or toxocara parasitic in cats.
Often, children who are in close contact with infected dogs become infected. Helminth larvae can be found on the surface of the animal’s hair, in dog feces, and even in the ground on which the dog walked. The prevalence of worms in cats is an order of magnitude lower.
Parasite morphology
Toxocars when they enter the human body die due to the lack of suitable conditions for their survival and the development of full-fledged mature individuals. Man, therefore, in their life cycle is a dead end branch. That is why the disease from the carrier is not transmitted to other people, in other words, toxocariasis is not contagious. In children, despite this, such a pathology is not at all a rare occurrence. What to do, our kids like to pet stray animals, delve into infected sand or soil. In addition, many parents do not teach children to pay due attention to hygiene. The result is toxocariasis!
The photo on the right clearly does not cause positive emotions. And imagine that the larvae of such a worm enter the body of your child! Yes, really creepy. Adult toxocaras in length can grow up to fifteen to eighteen centimeters. Their development from a larva to a mature form occurs in the intestines of the hosts - dogs and cats. Then the females secrete eggs into the external environment (up to two hundred thousand pieces per day), however at this time they are still immature, therefore non-infectious. The process of egg maturation in the soil takes up to twenty days, and in the conditions of the apartment they can remain a danger year-round, being in the hair of animals. A person becomes infected with an invasive form of eggs when swallowed; they usually get into their mouth from dirty hands. You can get infected at any time of the year, because the larvae are resistant to environmental factors, but often infection occurs in the warm months, when there are the most favorable conditions for the development of invasive forms.
What happens in case of infection
In the human body, toxocaras can only be in the larval stage. Once in the intestines, the invasive eggs transform into larvae, which then penetrate the bloodstream through the intestinal wall and, like roundworms, migrate from the pulmonary circulation to the pulmonary circulation, then enter the liver and lungs, settle there and form special granulomas. This happens most often, but in general, larvae can settle in any organs and tissues. The parasite is surrounded by a dense capsule, and thanks to it, it can remain viable for many years. Therefore, even if the treatment of toxocariasis in a person was successful, a relapse of the disease is possible.
Symptoms of the disease
Clinical manifestations will entirely depend on the severity of the response of the child’s immune system and on how widespread toxocariasis in the body is. Symptoms in children manifest themselves brighter, the higher the level of contamination. Often the disease is characterized by a latent or latent course, periods of exacerbation are replaced by remissions. In the body, toxocaras can exist from several months to many years. In extremely rare cases, as already mentioned, everything ends in death. Death occurs if parasites infect the central nervous system or heart.
Depending on which organs or systems of the body were affected, there are several forms of the disease: visceral, ophthalmic, skin and neurological. Signs of pathology in each case will vary.
1. Visceral toxocariasis
In children, this form is most common. The disease affects the internal organs. The more invasive larvae enter the body, the more pronounced the symptoms. Toxocariasis in this case is manifested by fever, accompanied by severe chills (this indicates damage to the lungs), swelling of the lymph nodes. Of the signs of the disease that are found only in the course of laboratory tests, one can distinguish an increase in blood levels of eosinophils and gamma globulins, an increase in the liver. The most common symptom of this form, which occurs in almost seventy percent of children, is a pulmonary syndrome, which is expressed in a dry cough, worse at night, shortness of breath, and blueness of the area around the mouth. There may also be wheezing in the lungs. If treatment of toxocariasis is not started on time, a person may develop progressive pneumonia. Timely diagnosis and adequate therapy is the guarantee that the disease will be defeated!
2. Ocular toxocariasis
This form usually occurs when helminths enter the body in small quantities. There is a pathology of optic neuritis, keratitis, the development of chronic endophthalmitis, uveitis, and the formation of granulomas. A doctor, when examined in the vitreous body, can detect floating larvae forming an abscess surrounded by an inflammation zone.
3. Cutaneous toxocariasis
With this form, allergic reactions usually occur in the form of eczema, urticaria, various rashes. In this case, the affected areas become inflamed, can swell strongly, turn red. The appearance of a rash is accompanied by a painful, intolerable itching. The strongest and brightest inflammation is found in the migration zone under the skin of the larvae and along the vessels.
4. Neurological toxocariasis
This is the most dangerous and severe form, because in this case parasites enter the parts of the nervous system, and this is fraught with all kinds of neurological disorders, including memory impairment, restlessness, problems with behavior, irritability, difficulty reading, hyperactivity. In some cases, convulsions and epileptic seizures occur.
Blood test for toxocariasis: transcript
In a laboratory blood test, the most persistent symptoms in the case of this disease are an increase in the number of eosinophils to a high level (they can reach up to 90 percent of the number of all white blood cells) and the development of a leukemoid reaction with an eosinophilic focus. White blood cells in total also increase to 10-15x10 9 / l, and the erythrocyte sedimentation rate increases sharply. The total number of red blood cells and hemoglobin against the background of an acute blood reaction can decrease.
In addition, in the early stages of infection, hypergammaglobulinemia is observed - a significant increase in IgM immunoglobulin in the blood, and then IgG immunoglobulin. At the same time, the number of serum albumin drops sharply. The level of the total IgE fraction, IgE reagin immunoglobulins (antibodies), and circulating immune complexes is also gradually increasing, resulting in severe allergic manifestations.
The final point in the study puts the titer of antibodies. Infection is diagnosed with a titer of 1: 200, if it is higher than 1: 800, then the disease is already in the clinical stage. In this case, it is urgent to begin treatment of toxocariasis in children.
Visual inspection
It is worth noting that, in addition to prescribing a laboratory test, the doctor also conducts an external examination of the child. If there is a disease during the analysis of the skin integument, he may notice tuberculous nodules on the palms and feet. Inside these nodules are just larvae. Also, a specialist can detect dystrophy of hair and nails.
Disease treatment
To date, there is no universal way to completely get rid of parasites. There are quite effective drugs, but the difficulty is that the larvae are surrounded by a protective capsule, and drugs do not enter it. Medicines work well only on parasites that are in the process of migration. And yet, how to treat toxocariasis?
The most effective are considered such drugs as Albendazole, Vermox, Mintezol, Ditrazin. But keep in mind that they are all toxic and therefore dangerous to the liver. Only under the supervision of a doctor and in a strictly defined dosage should they be used to cure toxocariasis. Reviews of many parents indicate that in children, after taking such medications, nausea begins, and an intestinal upset occurs. Therefore, before using any of these tools, you need to do a liver test and a blood test. Best of all, parents speak about Vermox. They say that of all other medicines, this is better tolerated by children and rarely causes side effects. Take the medication in a course of two to four weeks, one tablet twice a day.
When using Mintezol, the dose is calculated based on the weight of the child. You need to drink it without interruption for ten days. The medicine is quite well absorbed, but can cause serious negative effects, such as headache, nausea, neurological disorders, and appetite disorders. At the same time, the medication does not disturb the work of the respiratory system and heart. All side effects are quickly eliminated after the cancellation of the drug. According to the peculiarities of its use, the drug “Ditrazin” is similar to it. It is also not without negative effects - it can provoke a fever.
Doctors recommend the treatment of ocular or visceral toxocariasis with Albendazole or its equivalent, Tiabendazole.
Forecast
Usually, treatment of toxocariasis in children is successful. But do not wait for spontaneous healing and do not delay with the course of therapy, otherwise the larvae can penetrate the vital organs, affect the eyes, heart. A child who is diagnosed with the disease should be under dispensary observation by an infectious disease specialist until the condition is completely normalized. Monthly after the end of treatment, blood control and enzyme immunoassay are performed. A repeated therapeutic course is prescribed three months later, not earlier. It happens that the treatment is delayed for two to three years before it is possible to completely destroy the toxocar. The dosage and course of taking medications cannot be increased, since it is not only ineffective, but also unsafe. The patient is under control for three years.
How to protect yourself from illness
Prevention of toxocariasis includes the following:
- seasonal deworming of domestic animals through the use of anti-nematode agents;
- do not allow faecal contamination of dogs in your garden, garden plot;
- plant crops that prevent the maturation of toxocar eggs (legumes, delphinium, marigolds, marigold and others);
- do not allow the child to eat soil contaminated products;
- thoroughly rinse and pour boiling water over raw vegetables and fruits before giving them to children;
- before use in food, subject the meat of the paratenic hosts (poultry and wild birds, pigs) to a good heat treatment.