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 Congenital syphilis can be best diagnosed by- and explain in detail?
Ans. is 'a' i.e., IgM FT A - ABS * As Ig M does not cross placenta, its presence in neonatal serum confirms congenital syphilis and helps differentiating it from seropositivity due to passively tranfered maternal antibodies. The tests to detect IgM are# FTA-ABS (19S IgM FT A-ABS)# Syphilis Capita M test"For measurment of IgM in neonate in whom congenital syphilis is suspected, the syphilis capita M test and the 19S IgM FTA-ABStest are available". - Harrison 16th/e 982Note - 15th/e Harrison says, "No commercially available IgM test is recommeded forevaluation of infant with suspected congenital syphillis" -------- Harrison 17th/e 1043