[Correlation between early (Fernandez) and late (Mitsuda) reactions in non-contact children and adolescents without manifestations of leprosy, tested with human lepromin and different concentrations of armadillo antigen in 3 double-blind trials].

The authors carried out 3 double blind trials to determine the correlation between the early and the late lepromin reactions and to verify the practical and control values of the 48 hours or Fernandez reaction. Children and adolescents non-contacts were tested with human lepromin (40 x 10(6) bacilli/ml) and different concentrations of armadillo lepromin (160, 40, 20, 10, 5, 2,5, and 1 x 10(6) bacilli/ml). The conclusions are as follows: 1. The coefficients of correlation (r values) point out that the correlation between the two reactions is poor or almost null. 2. The negative or doubtful reactions, the most often observed, have no practical value because they are almost always followed by a positive Mitsuda reaction. 3. The positive Fernandez reaction was always followed by a positive Mitsuda reaction. Thus it has practical importance. However as the frequency of early positivity is low with human and armadillo lepromin of lower concentrations, recommended in routine testing, the 48 hours reading is unnecessary and without control value. It would represent a loss of time and money.