What is seborrh[oe]a?#

Seborrh[oe]a is a disease of the sebaceous glands, characterized by an
excessive and abnormal secretion of sebaceous matter, appearing on the
skin as an oily coating, crusts, or scales.

In many cases the sweat-glands are likewise implicated, and the process
may also be distinctly, although usually mildly, inflammatory.

#At what age is seborrh[oe]a usually observed?#

Between fifteen and forty. It may, however, occur at any age.

#Name the parts most commonly affected.#

The scalp, face, and (less frequently) the sternal and interscapular
regions of the trunk. It is sometimes seen on other parts.

#What varieties of seborrh[oe]a are encountered?#

Seborrh[oe]a oleosa and seborrh[oe]a sicca; not infrequently the disease
is of a mixed type.

#What are the symptoms of seborrh[oe]a oleosa?#

The sole symptom is an unnatural oiliness, variable as to degree. Its
most common sites are the regions of the scalp, nose, and forehead. In
many instances mild rosacea coexists with oily seborrh[oe]a of the nose.

#Give the symptoms of seborrh[oe]a sicca.#

A variable degree of greasy scalines, which may be seated upon a pale,
hyperaemic or mildly inflammatory surface.

The parts affected are covered scantily or more or less abundantly with
somewhat greasy, grayish, or brownish-gray scales. If upon the scalp
(_dandruff_, _pityriasis capitis_), small particles of scales are found
scattered through the hair, and when the latter is brushed or combed,
fall over the shoulders. If upon the face, in addition to the scaliness,
the sebaceous ducts are usually seen to be enlarged and filled with
sebaceous matter.

#Describe the symptoms of the ordinary or mixed type.#

It is common upon the scalp. The skin is covered with irregularly
diffused, greasy, grayish or brownish scales and crusts, in some cases
moderate in quantity, in others so great that large irregular masses are
formed, pasting the hair to the scalp. If removed, the scales and crusts
rapidly re-form. The skin beneath is found slate-colored, hyperaemic or
mildly inflammatory, and exceptionally it has in places an eczematous
aspect (_eczema seborrhoicum_). Extraneous matter, such as dust and
dirt, collects upon the parts, and the whole mass may become more or
less offensive. There is a strong tendency to falling-out of the hair.
Itching may or may not be present.

[Illustration: Seborrh[oe]a (Eczema Seborrhoicum).]

#Describe