It is an odd commentary on medical life that the conditions most commonly met are those things of which we are most ignorant.
It is further odd, how, in many of the inflammatory syndromes of unsure knowledge, seborrhea is obviously present.
Seborrhea starts out in a logical sort of way, justifying the classifications of oleosa and sicca, but when it evolutes into that syndrome which we call seborrhoeic dermatitis our thinking becomes confused. Sabouraud worked out a scheme of a succession of bacterial infections which is too pat and automatic. In two of our American texts we find these statements:
"Seborrhoeic dermatitis is basically a constitutional diathesis affecting the skin, and often inborn physiologic trait, which usually can be controlled but not cured." (Pillsbury)
"There are more etiologic factors involved than are understood at present. That they are concerned with chemical processes and hormone or vitamin
MURRELL TW. Seborrhea—a Neglected Factor in Mixed SyndromesA Clinical Discussion. AMA Arch Derm. 1957;76(4):415–418. doi:10.1001/archderm.1957.01550220023004