In Russia, an intradermal Diaskintest® drug has been designed, which is a 
recombinant tuberculosis allergen based on M. tuberculosis-- specific proteins: 
ESAT-6 and CFP-10 produced by a genetically modified Escherichia coli culture. 
Diaskintest® test and Mantoux test with 2TE PPD-L were concurrently carried out 
in 300 children and adolescents with tuberculosis and followed up in risk groups 
at a tuberculosis dispensary to determine the sensitivity of the new skin test 
in active tuberculosis infection. Diaskintest® showed a high sensitivity not 
only in active tuberculosis, but also in occult, the so-called latent, 
tuberculosis infection. This is suggested by the following evidence. The high 
percentage (83.8%) of positive responses to Diaskintest® is noted in children 
and adolescents with tuberculosis, receiving an intensive course of 
chemotherapy. Negative tests were observed only in minor forms at the resolution 
stage. In the children who had completed treatment, positive tests were seen in 
78.3%, moreover in those with prior tuberculosis of intrathoracic lymph nodes; 
negative tests were observed not earlier than 18 months after start of 
treatment. The highest sensitivity of Diaskintest® was shown in children with 
early primary tuberculosis infection and through family contact with 
bacteria-excreting subjects (91.7%). These children may be judged with the 
highest assurance to have latent tuberculosis infection, the population of which 
is in an active state at the moment of the study. The children with early 
primary tuberculosis infection, but in no family contact with bacteria-excreting 
individuals, showed a lower percentage of positive responses to Diaskintest® 
both before (37.5%) and after (10%) treatment, which suggests that there must be 
a lower bacterial burden in the child. A high percentage of positive responses 
to Diaskintest® (76.2%) were found in subjects with hyperergic reactions to 
tuberculin. These were in only 16.7% in the group of patients receiving 
preventive therapy. In children and adolescents with a persistent positive 
Mantoux test (for more than 3 years), the response to Diaskintest® was negative 
in most cases since in early infection when mycobacteria propagated, the 
reaction to the drug was positive, but as 3 years pass the probability of the 
infection transition to the persistence stage is high--at that time the response 
to Diaskintest® becomes negative. Diaskintest® induces no delayed 
hypersensitivity associated with BCG vaccination, suggesting its high 
specificity. There were no positive reactions in patients with nonspecific lung 
diseases.