Vitrotest® Anti-Toxocara

• Solid phase: breakable microplate ELISA is coated Toxocara canis larvae antigens.
• Conjugate: a monoclonal antibodies to human IgG conjugated to horseradish peroxidase.
• Chromogen: ready to use TMB solution.
• Volume of sample for analysis: 10 μl.
• Assay time: 1h 15 min.

Toxocariasis is an widespread parasitic disease of humans caused by infection with the second stage larvae of two main species of parasitic nematodes, Toxocara canis and Toxocara cati. The role of toxocaras in human disease was disclosed in the 1950th by Wilder and Beaver et al. who first identified toxocara larvae in ocular and visceral tissues respectively.

Adult worms of T. canis and T.cati live within the lumen of the small intestine of dogs and cats respectively which serve as definitive hosts for these helminths. Unembryonated eggs produced by adult worms are shed in the feces of the definitive hosts. Eggs embryonate in the environment, and could be ingested by definitive hosts as well as accidental, paratenic hosts. After ingestion by the definitive hosts, microscopic (300 µm long and 20 µm in diameter) larvae hatch in the intestine, penetrate the intestinal wall, reach lungs via bloodstream, penetrate alveolar walls, ascend the bronchial tree to the throat where they are swallowed, and mature into adult worms. In humans and other paratenic hosts, the larvae are unable to undergo the full development cycle described above; instead, they are carried by the circulation to a wide variety of organs and tissues (liver, heart, lungs, brain, muscle, eyes), and cause severe local reactions that are the basis of toxocariasis.

The degree of host damage, and the concomitant signs and symptoms, varies with regard to which tissue has been invaded; the liver, lungs, and CNS (including the eyes) appear to be most sensitive. In the eye, migrating larvae can damage the retina, inducing granulomatous reactions leading to impaired sight or even loss of sight. The number of migrating larvae and the age of the host are two additional factors defining the presence and severity of symptoms.

Lifespan of the larvae could be as long as several years, and clinical disease could present in any time during this period, or even later, representing pathological immune response to dying or dead larvae.

For most people, an infection with these helminths causes no symptoms. Possible symptoms symptoms are nonspecific and include fever, fatigue, anorexia, or lymphadenopathy. Pulmonary symptoms and abdominal symptoms are similar to those under many other diseases; they are present when larvae migrate to the lungs or abdominal organs, respectively. Neurologic findings are diverse and also nonspecific.