Before McKee and Andrews1 summarized the condition in 1924, little was known about ectodermal dysplasia of the anhidrotic type. Since then, more cases have been reported,2 over 30 in all. The diagnosis is not difficult when the condition is fully developed, and the term ectodermal dysplasia has not been applied when the defects occur singly.
To evaluate a given case fully, one must be familiar with the organs or tissues that are derived from the primitive ectoderm. They are as follows:3 (1) the nervous system, including the adrenal medulla; (2) the epidermis; (3) the lining cells of the sebaceous, sudoriferous and mammary glands; (4) the hair and the nails; (5) the epithelium lining the nose, adjacent air sinuses, cheeks and roof of the mouth and also the epithelium of the cornea, conjunctivas and lacrimal glands; (6) the enamel of the teeth; (7) the anterior lobe of the pituitary gland, and