P7.87 A controlled study of liquid nitrogen efficacy in treatment of alopecia areata involving less than 25% of the scalp

Matard B, Jouanique C, Abdennader S, Saada V, Nico F, Assouly P, Reygagne P.

Sabouraud Center, Saint Louis Hospital, Paris

Liquid nitrogen (LN) efficacy in the treatment of alopecia areata(AA) has never been studied in a controlled trial to our knowledge.

Patients and methods: We studied 39 patients (18 males, 21 females). Ages ranged from12 to 67 (average 32 years). Patients with patchy AA were enrolled regardless of age unless if they had : 1) AA involving more than 25% of the scalp, 2) just a single patch with diameter less than 5 cm, or 3) one or several patches over 10 cm diameter. LN was applied with a cotton swab once weekly for 5 weeks. Clinical evaluation was made 3 weeks after the fifth application. Each patch was measured and a sketch was drawn.  In order to have a control, only half of the patchy area was treated. The treated side of the scalp was randomly selected. “Big“ patches (over 5 cm diameter) were treated only on the randomly selected half of the patch.

Results: 15 patients dropped out before the 8^th week (4 after 1 week, 5 after 2 weeks, 1 after 3 weeks, 5 after 5 weeks). For all these patients except one (for whom it was difficult to conclude), there was no difference between the treated side and the control side at the time they stopped the study. Among the 25 patients who were evaluated at 8th week, it was easily concluded (because regrowth (9/25 =36%) or lack of regrowth (11/25=44%) was homogeneous i.e. the same between the treated patches and control patches)  that no clear difference could be seen for 21 of them (84%).This lack of difference was obvious in 60% (15/25) of the patients who had a homogeneous evolution but more difficult to determine in 5 patients where a very slight difference could have been argued in favour of  LN efficacy. 4 patients had non-homogeneous evolution (mix of regrowth and lack of regrowth on treated and control areas) and it was difficult to make a conclusion in these cases. 9 “big” patches were treated (10 patients) and evaluated at the 8th week: there was no difference between treated and control sides in 8 patients (90%).

Comment: In spite of the limited number of patients, this study seems to show that LN has no or little effect in AA treatment. This result is completely different from the 2 previous studies which displayed a ”cure rate” of 71% for one [1] and new hair growth in over 60% of the involved area in 97% of cases for the other [2]; however, these studies  were not controlled.

References: 1. Huang P,Huang S,Wei G:123 cases of alopecia areata treated with liquid nitrogen cryothérapie .J Clin Dermatol 15:269,1966.

2. Lei Y et al:Effect of superficial hypothermic cryothérapie with Liquid Nitrogen on Alopecia Areata.Arch Dermatol 127:1851-1852,1886.