Microdissection study of the incidence of branched eccrine sweat glands and the number of eccrine glands per unit area of infants' and childrens' skin.

That branched eccrine sweat glands occur has rarely been mentioned in the literature, and their incidence has never been determined. All eccrine glands in 0.5-cm2 pieces of anterior trunk skin of 59 children were microdissected, and the total number of glands and the number of branched eccrine glands determined. One-hundred fourteen of 17,539 (0.65%) were branched, 90% in the middermis and 10% at the epidermis. The apparently normal anatomic property that almost 1% of eccrine sweat glands are branched has not hitherto been appreciated. One doubly branched gland was found. Patients with leukemia (11 in the study) possibly had more branched glands than nonleukemic patients of the same body size. The best statistical relation of the number of sweat glands per unit area of skin (GUA) to surface area (SA) or age in children was the natural logarithm of GUA versus the reciprocal of surface area: LnGUA = (0.2205 X 1/SA) + 5.42. This result is consistent with the classical proposition that there is no important degree of formation of new eccrine glands, nor of loss, after birth, the density of glands per unit area of skin reducing as SA rises with growth during childhood.