LOCAL SENSITIZATION TO TUBERCULIN

Publisher Website
Google Scholar
Abstract
The characteristics of the "early" tuberculin reaction are demonstrated. This reaction occurs at the site of previous tuberculin tests. In contrast to the immediate and delayed reactions, it starts 3 to 6 hours after the injection, reaches its maximum at 12 hours and, in tuberculin-negative cases, usually disappears within 48 hours. In some cases, however, it may persist for 48 hours and, in the case of only one reading at 48 hours, this may lead to false positive readings. In tuberculin-positive cases, the early reaction is combined with the delayed reaction, usually showing only one reaction which starts also 3 to 6 hours after injection, reaches its maximum at 12 hours, and persists through 7 days or turns to negative earlier. The early reaction seems to be a type of Arthus'' phenomenon due to a local sensitization of the skin by tuberculoprotein injected in previous tests. It was demonstrated that an early reaction might be found as long as 7 years after the last tuberculin test, but no such reaction was noted 23 years after the last test. In the sensitized area of the skin the delayed reaction may also be accelerated in tuberculin-positive persons, particularly after several repeated tests in the same area. In low-grade reactivity it may disappear as soon as 48 hours after the test. This may lead to false negative readings. In view of the possibility of false positive and false negative readings in a sensitized area, it is necessary to use a new site for each tuberculin test.

This publication has 0 references indexed in Scilit: