You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Invasive amoebiasis can be best diagnosed by - and explain in detail?
Option 1,3 Amoebic Lectin Antigen (Gal/NAG lectin) is the principle virulence factor, present on the surface of trophozoites of pathogenic E. histolytica. Its various pathogenic mechanisms are: Adhsion, Cytotoxicity and Complement resistance. Serological tests (ELISA, IHA etc.) become positive only in Invasive amoebiasis. ELISA: detects 170kDa of lectin Ag in stool with 95% sensitivity and specificity. It can also differenciate pathogenic E. histolytica from non pathogenic E. disper (Negative for Lectin Ag). IHA: it uses crude Ag to detect Amoebic Abs (IgG). IgG appears only in the later stage of intestinal amoebiasis. Option 2 Electrophoresis: it is used for Isoenzyme (Zymodeme) analysis. Option 4 Complement fixation test: it is not used in diagnosis of amoebiasis.