hiloderm_) is a
common form of cutaneous syphilis, appearing usually in the first six or
eight months, and consists of a more or less generalized eruption of
pea- to dime-sized or larger, flat, rounded or oval, firmly seated,
more or less raised, dull-red papules; with at first a smooth surface,
which later usually becomes covered with a film of exfoliating
epidermis. The papules, as a rule, develop slowly, remain stationary
several weeks or a few months, and then pass away by absorption, leaving
slight pigmentation, which gradually fades; or they may undergo certain
modifications. In most cases it responds rapidly to treatment.

[Illustration: Small-papular Syphiloderm.]

[Illustration: Fig. 53. Palmar Syphiloderm.]

#What modifications do the papules of the large-papular syphiloderm
sometimes undergo?#

They may change into the moist papule and squamous papule.

#Describe the moist papule of syphilis.#

The change into the moist papule (also called _mucous patch, flat
condyloma_) is not uncommon where opposing surfaces and natural folds of
skin are subjected to more or less contact, as about the anus, the
scroto-femoral regions, umbilicus, axillae and beneath the mammae. The
dry, flat papules gradually become moist and covered with a grayish,
sticky, mucoid secretion; several may coalesce and form large, flat
patches. They may so remain, or they may become hypertrophic, warty or
papillomatous, with more or less crust formation (_vegetating
syphiloderm_).

[Illustration: Fig. 54. Annular Syphiloderm. (_After I.E. Atkinson._)]

#Describe the squamous papule of syphilis.#

This tendency of the large-papular eruption to become scaly, when
exhibited, is more or less common to all papules, and constitutes the
_squamous_ or _papulo-squamous syphiloderm_ (improperly called
_psoriasis syphilitica_). The papules become somewhat flattened and are
covered with dry, grayish or dirty-gray, somewhat adherent scales. The
scaling, as compared to that of psoriasis, is, as a rule, relatively
slight. The eruption may be general, as usually the case in the earlier
months of the disease, or it may appear as a relapse or a later
manifestation, and be limited in extent.

As a limited eruption it is most frequently seen on the palms and
soles--the _palmar and plantar syphiloderm_. Occurring on these parts it
is often rebellious to treatment.

[Illustration: Maculo-papular syphiloderm.]

#How are you to distinguish the p