Response to minoxidil in severe alopecia areata correlates with T lymphocyte stimulation.

Mitogen-induced T cell blastogenesis was determined in 47 patients with severe alopecia areata, before and after treatment with topical 5% minoxidil, and compared with control values. The group of 36 responders, who demonstrated terminal hair regrowth, showed significantly increased lymphocyte stimulation with concanavalin A and PHA before treatment, which decreased towards control values following hair regrowth. Lymphocytes from non-responders showed no significant differences from controls either before or after treatment. The results suggest that enhanced T cell blastogenesis may predict the response of severe alopecia areata to topical 5% minoxidil therapy.