oderma_.

[Illustration: Fig. 49.
Tuberculosis Verrucosa Cutis (patient had a coexistent pulmonary
tuberculosis).]

An ulcerative papillomatous or verrucous tuberculosis of the skin
(tuberculosis verrucosa cutis) is also occasionally noted, most commonly
seated upon the lower leg or the back of the hand. It may be slight or
extensive. Its mildest phase is the so-called verruca necrogenica.

#Describe verruca necrogenica.#

Verruca necrogenica is a rare, localized, papillary or wart-like
formation, occurring usually about the knuckles or other parts of the
hand.

It begins, as a rule, as a small, papule-like growth, increasing
gradually in area, and when well advanced appears as a pea, dime-sized
or larger, somewhat inflammatory, elevated, flat, warty mass, with
usually a tendency to slight pus-formation between the hypertrophied
papillae; the surface may be horny or it may be crusted. It tends to
enlarge slowly and is usually persistent, but it at times undergoes
involution.

[Illustration: Fig. 50.
Tuberculosis Cutis (Verruca Necrogenica). (_After Model in Guy's
Museum._)]

#State the etiology.#

Heredity, insufficient and unwholesome food, impure air, and the like
are predisposing. The tubercle bacillus is the immediate exciting cause.

The disease usually appears in childhood or early adult life, and not
infrequently follows in the wake of some severe systemic disease.
Etiologically it is identical in nature with lupus.

#How is the tuberculous ulcer to be differentiated from syphilis?#

By the peculiar character of the tuberculous ulceration, the absence of
outlying tubercles and infiltration, together with its history, course,
and often the presence of other tuberculous symptoms.

#State the prognosis.#

These various types of tuberculosis cutis are, as a rule, more amenable
to treatment than that form known as lupus vulgaris (_q. v._).

#What is the treatment of these forms of tuberculosis cutis?#

Constitutional remedies, such as cod-liver oil, iodide of iron or other
ferruginous tonics, together with good food and pure air; phosphorus
one-hundredth to one-fiftieth of a grain three times daily is also of
benefit in some cases.

The local treatment consists in thorough curetting and the subsequent
application of a mildly stimulating ointment. The several other plans of
external treatment employed in lupus (_q. v._) are also variously
practised. In recent years the _x_-ray an