What are the clinical appearances and behavior of this type of tuberculous ulceration?

It is usually superficial, has thin, red, undermined edges of a violaceous color, and an irregular base with granulations covered scantily with pus. As a rule, it spreads gradually as a simple ulceration, with but slight, if any, outlying infiltration. Subjective symptoms of a painful or troublesome character are rarely present. Its course is usually progressive but slow and chronic.

Other symptoms of tuberculosis are commonly to be found.

Are other forms of tuberculosis cutis met with?

A papulo-pustular eruption is sometimes observed, especially on the upper extremities and face; sluggish and chronic in character and leaving small pit-like scars; has been known as the _small pustular scrofuloderma_.

[Ill.u.s.tration: 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 ma.s.s, with usually a tendency to slight pus-formation between the hypertrophied papillae; the surface may be h.o.r.n.y or it may be crusted. It tends to enlarge slowly and is usually persistent, but it at times undergoes involution.

[Ill.u.s.tration: 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?

Const.i.tutional 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 and Finsen light plans have, in a measure, supplanted the previous methods of treatment. They are slow, however, and might be, especially the _x_-ray, more satisfactorily employed as a supplementary measure.

Ainhum.

Describe ainhum.

Ainhum is a disease of the African race, met with chiefly in Brazil, the West Indies, and Africa, and consists of a slow but gradual linear strangulation of one or more of the toes, especially the smallest, resulting, eventually, in spontaneous amputation. The affected toes themselves undergo fatty degeneration, often with increase in size, and are, when strangulation is well advanced, considerably misshapen. The nature of the disease is obscure.

_Treatment_ consists, in the early stages, of incision through the constricting band; when the disease is well advanced, amputation is the sole recourse.

Mycetoma.

(_Synonyms:_ Fungous Foot of India; Madura Foot; Podelcoma.)

Decribe mycetoma.

It is a disease involving usually the foot, and is met with chiefly in India. It is characterized by swelling and the formation of tubercular or nodular lesions which break down and form the external openings of sinuses which lead to the interior of the affected part. These discharge, and are studded with, whitish granules or black, roe-like ma.s.ses, mixed with a sanious or sero-purulent fluid. The whole part is gradually disintegrated, the process lasting indefinitely. Its nature is obscure; it is thought to be due to a fungus.

_Treatment_ consists in the early stages, when the disease is limited, of thorough curetting and cauterization; later, after the part is more or less involved, amputation, at a point well up beyond the disease, becomes necessary. Pota.s.sium iodide internally may exert a favorable influence.

Perforating Ulcer of the Foot.

Describe perforating ulcer of the foot.

Perforating ulcer of the foot is a rare disease, consisting of an indolent and usually painless sinus leading down to diseased bone. The external opening, which is through the centre of a corn-like formation, is small, and may or may not show the presence of granulations. The affected part is commonly more or less anaesthetic and of subnormal temperature. One or several may be present, either on one or both feet.

The most common site is over the articulation of the metatarsal bone with the phalanx of the first or last toe. The disease is dependent upon impairment or degeneration of the central, truncal or peripheral nerves.

What is to be said in regard to the prognosis and treatment?

Treatment, which is, as a rule, unsatisfactory, consists in the maintenance of absolute rest, and the use of antiseptic and stimulating applications. Amputation is also resorted to, but even this is at times futile, as a new sinus may appear upon the stump.

Syphilis Cutanea.

(_Synonyms:_ Syphiloderma; Dermatosyphilis; Syphilis of the Skin.)

In what various types may syphilis manifest itself upon the integument?

Syphilis may show itself as a macular, papular (rarely vesicular), pustular, bullous, tubercular and gummatous eruption; or the eruption may be, in a measure, of a mixed type.