Dark ground microscopy is used for:: (A) TPI, (B) Kahn's test, (C) FTA-ABS, (D) VDRL
Answer is A. In TPI test , the serum of patient with complement and T.pallidum maintained in a complex medium anaerobically . If the antibodies are present , the treponemes are rendered non motile, when examined under dark ground illumination Kahn test and VDRL test are non specific antigen antibody test ,cardiolipin antigen is used. FTA-ABS is specific antigen antibody test