For over 100 years many different methods have been used to determine
capillary resistance as a measure of small vessel fragility. There is
still no firm agreement as to the most suitable method; the procedure
is not standardized and an objective system for measurement is lacking
. We have developed a computerized system that makes it possible to co
unt petechiae and determine their area without the results varying wit
h different examiners. Although we tried to keep the conditions for ou
r examinations constant, we found a wide individual spread. In spite o
f this, the capillary resistance of atopic subjects was significantly
lower than that of healthy persons.