Fourteen patients, four male and 10 female and ranging in age from 11
to 57 years, affected by longstanding alopecia areata that had not res
ponded to sensitizing treatments, were submitted to scalp biopsy. Five
patients had alopecia totalis and nine had alopecia universalis. The
biopsy was performed on a scalp area that had been bald for greater th
an or equal to 1 year. We distinguished four distinct pathological pat
terns, which we termed ''established bald patch,'' ''early regrowth,'
' ''telogen,'' and ''scarring,'' in four, seven, one, and two patients
, respectively. Our study shows that, from a pathological point of vie
w, nonresponder patients constitute a heterogeneous population. The pa
thological study of the scalp helps predict therapeutic failure only i
n the small proportion of nonresponder patients that shows a scarring
pathological pattern.