[Human alveolar echinococcosis and an overview of the occurrence of Echinococcus multilocularis in animals in the Czech Republic]. / Humánní alveolární echinokokóza a prehled výskytu tasemnic Echinococcus multilocularis u zvírat v Ceské republice.

Human alveolar echinococcosis (AE) is caused by larval stages of the tapeworm Echinococcus multilocularis. In the Czech Republic, screening tests to detect the specific infectious agent have been performed since 1998. The first AE cases were diagnosed in 2007, and until 2014, a total of 21 diseases were recorded. In accordance with radiological, histological, and/or PCR data, serological examinations of 699 individuals helped to reveal 15 additional AE cases in the period of 2015-2016. From the cumulative data for 1998-2016, it appears that of 2,695 patients examined, 36 (18 men and 18 women) were diagnosed with AE. Their age at diagnosis ranged from 20 to 82 years and was lower for women (mean 43.7, median 39.5) than for men (50.9 and 57.5, respectively), but the difference was not statistically significant. In the period of 2007-2016, the mean annual incidence rate was 0.034 cases/100 000 population. Our study indicates an ongoing increase in AE cases. The disease can be autochthonous in nature, as evidenced not only by some case history data but also by the detection of the larval stages in wild boar (Sus scrofa). AE risk to humans in the Czech Republic is discussed in the context of the known data on the presence of various parasite developmental stages in animals.

[The ocular form of larval toxocariasis in the Czech Republic]. / Ocní forma larvální toxokarózy v Ceské republice.

The damage of the eye is one of the clinical syndromes of the Toxocara infection, caused by the migration activity of the Toxocara canis and Toxocara cati larvae. Ocular larva migrans (OLM) lesions mostly occur unilaterally and frequently are diagnosed as retinoblastoma. The typical symptoms of OLM are presented in our publication. The first signs of the ocular infection most often include diminished vision, leukocoria, red eye and strabismus. Inflammatory intraocular reaction, caused as a response to the antigens, released from dead or dying larvae is often diagnosed. The living larvae are observed very rarely. The reason and a way of the ocular invasion are still not sufficiently cleared. The supposition that the ocular syndrome is caused by migration of single larvae, when the immunological response is light, was not reliably verified. Sometimes if the infection size was heavy, the eye can be invaded with systemic complications as well. The most common laboratory findings include an elevation of the immunoglobulins in the serum of the patient and the presence of Toxocara specific antibodies response in the vitreous and/or aqueous humor. An analysis of the humor in cases of presumptive OLM was made only in 8 patients because not all oculists are ready to take this material, mainly in children. Highly sensitive assay--ELISA reaction with specific excretory-secretory antigen (TES) was used. For discrimination between chronic and recent infection the method of measuring IgG avidity was applied.

[Diagnosis of the early phase of larval toxocariasis using IgG avidity]. / Diagnóza casné fáze larvální toxokarózy s pouzitím avidity IgG.

The term avidity used to express the strength of the bond between a serum specimen and a multivalent antigen. It is known that the avidity increases with time after antibody challenge and measurement of the avidity has been used diagnostically. Recently an assay measuring the IgG avidity of various virus infections and of toxoplasmosis was used to distinguish between acute and chronic infection. Our study was focused on the method to distinguish acute and chronic Toxocara infection, zoonosis caused by the larvae of dog and cat ascarids Toxocara canis and Toxocara cati known all over the world for the possibility of provoking the infestation of man, accompanied by visceral or ocular clinical manifestations. The infection is generally diagnosed by demonstration of specific immunoglobulins to Toxocara excretory-secretory antigens (TES) in sera of infected patients. Highly sensitive assays with specific antigens are necessary for detection of antibodies. The test that has been proved clinically useful is the ELISA reaction with TES antigens. This method detects the antibodies for months or even years after infection and this is the reason why the discrimination between chronic and recent infection is very difficult. For disrupting the hydrogen bond urea has been used. The index of avidity was calculated as the ratio of IgG values in sera treated with urea and the value of IgG in non-treated sera, multiplied by 100. An index up to 40 is considered as low avidity, that means freshly acquired infection (36 to 40 borderline) and more than 40 is high avidity. In the group of 1,376 patients only 5.09% low avidities were found. It means that predominantly patients in the chronic stage of infection attend examination.