Observations on the Delayed Blanch Phenomenon in Atopic Subjects11From the Department of Dermatology, Walter Reed Army Institute of Research, Walter Reed Army Medical Center, Wash. 12, D. C. and Dermatology Service, Walter Reed Army Hospital, Walter Reed Army Medical Center, Wash. 12, D. C

Major Michael J. Davis, Captain James C. Lawler
1958 Journal of Investigative Dermatology  
There is little doubt that the cutaneous vascular reactions of patients with atopic dermatitis are abnormal. Several reports, (1, 2, 3) stress the increased vasoconstrictor tendency of these patients. Recently, Lobitz and Campbell (3) have reported the delayed blanch phenomenon in patients with atopic dermatitis and have interpreted this as a paradoxical vasoeonstrictor response to acetyicholine. This phenomenon consists of paleness developing at the acetyicholine induced wheal and slowly
more » ... ing peripherally after 3-5 minutes. This report presents our observations on the delayed blanch phenomenon utilizing direct microscopic visualization of the superficial vessels. These observations lead us to believe that the delayed blanch is due to edema and not vasoeonstriction. METHODS Our method of studying the vascular reactions in the skin of atopic subjects involved the use of capillary microscopy by which direct visualization of the vessels is possible. The obvious advantage to this technic which has been described previously, (4) is that the necessity for interpreting vascular changes purely from gross variations in the skin color is decreased. Fifteen patients with atopic dermatitis were used as subjects and observations were made on the skin of the forearm. The site was prepared by repeated applications of cellulose tape until the keratin layer was removed. At least one hour was then allowed to elapse before testing was begun since the stripping occasionally induces a mild histamine reaction. Microscopic observation of the skin capillaries and photographs were made after the topical application of a drop of 1:10,000 acetyleholine solution to the previously stripped
doi:10.1038/jid.1958.24 fatcat:76fmzz3nybalbeca3zvswuop4a