Toxoplasmosis: treatment and prevention

The most effective in the acute phase of the disease: patients with a latent form of chronic acquired toxoplasmosis in treatment do not need. The effectiveness of etiotropic drugs for chronic toxoplasmosis is low, as chemotherapy and antibiotics practically do not affect endozoites in tissue cysts. Treatment of toxoplasmosis is indicated only with exacerbation of the process and with miscarriage (treatment is carried out beyond the period of pregnancy).

As etiotropic drugs for toxoplasmosis, pyrimethamine is used in combination with sulfonamides or antibiotics. The duration of the treatment cycle is 7 days. Usually 2-3 cycles are carried out with breaks between them in 10 days. It is possible to use co-trimoxazole on one tablet twice a day for 10 days. Carry out two cycles with an interval of 10 days. At the same time, calcium folinate is prescribed 2-10 mg per day or beer yeast 5-10 tablets per day. It is necessary to control the hemogram (possibly oppression of bone marrow hematopoiesis) and general urine analysis in dynamics.

Scheme of treatment of acquired toxoplasmosis

	Daily doses
A drug	1-3 days of the course		4-7th day of the course
	Adults, mg	Children	Adults, mg	Children
Pyrimethamine (once a day)	75	2 mg / kg	25	1 mg / kg
Sulfadizine (in four steps)	2000	100 mg / kg	2000	25 mg / kg
Calcium folinate	-	1 mg	2-10	1 mg

Pregnant are treated with spiramycin (accumulates in the placenta and does not penetrate the fetus). He is appointed for 3 million units three times a day for 2-3 weeks.

Treatment of toxoplasmosis in children is carried out with the same drugs as adult treatment: pyrimethamine at 1 mg / kg per day in two doses in combination with short-acting sulfanilamides at 0.1 g / kg per day in 3-4 doses. Treatment of toxoplasmosis is carried out in cycles: 5 days take pyrimethamine, and sulfanilamide preparation for 2 days longer - 7 days. Carry out three cycles with interruptions between them at 7-14 days. Additionally, calcium folinate is prescribed for 1-5 mg once every 3 days during the course of treatment to eliminate the side effects of antifolates (pyrimethamine, sulfonamides). The same course of treatment according to the indications (for example, chronic form of the disease, immunodeficiency state, exacerbation of chorioretinitis) is repeated after 1-2 months.

On the second place on efficiency there are macrolides, possessing less toxicity. Spiramycin is prescribed for 150 000 U / kg per day in 2 doses for 10 days, roxithromycin - 5-8 mg / kg per day, azithromycin - 5 mg / kg per day for 7-10 days. With an exacerbation of chronic toxoplasmosis, usually one course of etiotropic treatment is sufficient for 7-10 days.

Pathogenetic treatment of toxoplasmosis is carried out depending on the nature of organ pathology. If necessary, prescribe immunocorrecting drugs, vitamins, desensitizing drugs.

Patients with toxoplasmosis with HIV are prescribed the same drugs as other patients: pyrimethamine - on the first day of 200 mg in combination with sulfadiazine (1 g four times a day), clindamycin (0.6 g six times per day) or spiramycin (3 million units three times a day). At the same time, patients take calcium folinate 10-50 mg per day. The course of treatment is not less than 4 weeks, then a secondary prevention is prescribed to prevent relapses: pyrimethamine 50 mg per day and sulfadiazine 0.5 g four times a day. In connection with the complexity of diagnosis and the severity of the course of cerebral toxoplasmosis treatment is prescribed even with a suspicion of the disease. Improvement within 2-4 weeks of treatment with a high probability indicates the presence of toxoplasmosis.

Etiotropic treatment of toxoplasmosis is assessed by clinical signs: improvement of the general condition of the patient, disappearance of lymphadenitis; less severity of hepatolienal syndrome, signs of encephalitis, eye damage; no relapse of the disease for 12 months or more. The results of serological studies, evaluating the effectiveness of etiotropic treatment, are not used, as the titres of specific antibodies do not correlate with the nature of the clinical course of the disease.

Prognosis for toxoplasmosis

Acquired toxoplasmosis has a favorable prognosis, because the latent form predominates without clinical manifestations. The septic forms observed in AIDS patients and in patients with an immunodeficiency state of another etiology are severe and can result in death.

Clinical examination

Clinical follow-up needs patients with acute form of chronic toxoplasmosis acquired and recurrent, as well as seropositive antigens to toxoplasma HIV-infected patients. The amount and timing of clinical observation depends on the clinical form of toxoplasmosis and the nature of the course of the disease. With congenital toxoplasmosis in children, depending on the residual phenomena, the issue of clinical examination is decided together with neuropathologists, ophthalmologists and other physicians. Some patients need lifelong follow-up care (with eye damage if etiotropic treatment is ineffective, seropositive to toxoplasma antigens HIV infected patients).

[1], [2], [3], [4], [5], [6], [7], [8], [9]

How to prevent toxoplasmosis?

Theoretically, the most radical way of preventing human toxoplasmosis is elimination (Latin Eliminare - exclusion, removal) and reliable sanation (Latin Sanacio - treatment) of the final host of the parasite, i.e. Cat. In this sense, the prevention of toxoplasmosis is similar in its content to the prevention of rabies. There is no doubt that the complete destruction of stray cats and effective veterinary supervision of domestic cats - a pledge if incomplete recovery of synanthropic foci of toxoplasmosis, then in any case, reducing the impact of the population in them in tens and thousands of times. And what is especially important, such measures will serve as a reliable guarantee of prevention of cases of congenital toxoplasmosis. Unfortunately, no experience of radical prevention of toxoplasmosis has been undertaken in any country yet. Moreover, up to now all the recommendations for the prevention of toxoplasmosis are based on the tacit acknowledgment of the inability to effectively influence the final host of the parasite - the cat.

Taking into account the above, it seems to us quite timely to start developing a system of active prophylactic antitoxoplasmosis measures and to organize verification of its effectiveness in strictly controlled epidemiological experiments. We are talking about the sensitivity of various stages of the parasite to external factors, including chemical reagents. The oocysts are most resistant to environmental factors. The stability of tachyzoites and tissue cysts is extremely low, they die even under the influence of tap water. That is why it is necessary to insist on carrying out such a simple measure as washing hands after contact with raw meat. The temperature of 100 ° C is absolutely intolerable for tissue cysts. Freezing meat at -20 ° C also guarantees the death of cysts.

Specific prophylaxis of toxoplasmosis

The main measures for the prevention of congenital toxoplasmosis are the timely examination of women of childbearing age and pregnant women in women's consultations. In HIV-infected patients, primary and secondary prophylaxis of toxoplasmosis is performed. The goal of primary prevention is to prevent the infection of T. Gondii or the development of toxoplasmic encephalitis in persons with a latent course of the disease. In HIV-infected with a positive serological response to toxoplasmosis, chemoprophylaxis with etiotropic drugs is carried out. The goal of secondary prevention or maintenance treatment is to prevent relapses of toxoplasmic encephalitis in AIDS patients.

Nonspecific prophylaxis of toxoplasmosis

Prophylaxis of toxoplasmosis consists in careful heat treatment of meat products and milk; observance of rules of personal hygiene, especially in risk groups (veterinarians, meat-packing plant workers, hunters, etc.); prevention of pollution of children's sandboxes by excrement of cats.