[The dynamics of antibodies with IgD-class cardiolipin and treponemal group specificity in syphilis assessed quantitatively by radial immunodiffusion].

150 sera (positive at the VDRL, ELISA-Reiter, FTA-ABS tests) were tested by IDRS for the IgD quantification in syphilis. They were collected from men, 25-45 years old, in different stages of the disease, treated or not. The reference normal values for the seric IgD were established on 154 sera taken from men, 25-45 years old, apparently healthy: 0-131.2 UI/ml, with an average of 29.92 +/- 29.61 UI/ml. The IgD values with cardiolipin or group treponemal specificity were obtained from the difference between the values of the immunodiffusion diameters produced by sera, before and after the complete absorbtion with VDRL antigen or delipidated treponemal suspension. The individual values for each serum, mean +/- SD, and the percent values against the total IgD, for each stage of the disease were calculated. The medium levels of the total IgD range within normal limits, except for epsilon 2, where they are considerably higher than normal (52.53 +/- 26.66 UI/ml). All the individual minimal values, between 7.09 and 14.89 UI/ml, are higher than the normal minimal values, under 3.54 UI/ml. Treponemal IgD are present in all the sera in all stages of the disease and the cardiolipin IgD are completely absent. The mean values of the treponemal IgD are about 7-9 UI/ml, with a maximum of 19.3 UI/ml in epsilon 2. A higher percent of treponemal IgD is found, around 30%, with a maximum of 36.7% in epsilon 2. The high percent of the treponemal IgD in epsilon latent and epsilon treated persistent positive shows a continuous activation of the circulating B lymphocytes by the treponemal antigens and therefore an active infectious process. The exclusive presence of the treponemal IgD in all the cases of syphilis, irrespective of the evolution stages, indicated the extremely specific diagnosis value of their detection.