<prompt> Which is false about syphilis -TPI gives definite diagnosisTPHA is earliest to be veVDRL is ve 1 week after appearance of chancreSerologically not different from yaws  <response>: Ans. is b i.e., TPHA is earliest to be ye About other options - TPI is a specific treponemal test and gives definite diagnosis. - VDRL test becomes positive 7-10 days after the appearance of primary chancre 3-5 weeks after acquiring the infection. - All treponemal and nontreponemal serological tests may be positive in nonveneral treponematoses eg yaws, pinta and endemic syphilis, so can not differentiate nonveneral treponematoses from syphilis. 