Essentials of Diseases of the Skin Part 64

It is not to be confounded with vitiligo, chloasma, or the macular syphiloderm. If in doubt, have recourse to the microscope.

State the method of examination for fungus.

The sc.r.a.pings are taken from a patch, moistened with liquor pota.s.sae, and examined with a power of three to five hundred diameters.

State the prognosis of tinea versicolor.

With proper management the disease is readily curable. Relapses are not uncommon.

[Ill.u.s.tration: Fig. 74. Tinea versicolor.]

What is the treatment of tinea versicolor?

It consists in daily washing with soap and hot water (and in obstinate cases with sapo viridis instead of the ordinary soap) and application of a lotion of--sulphite or hyposulphite of sodium, a drachm to the ounce; sulphurous acid, pure or diluted; carbolic acid, or resorcin, ten to twenty grains to the ounce of water and alcohol; or corrosive sublimate, one to three grains to the ounce of water. Sulphur and ammoniated-mercury ointments are also serviceable. The following used alone, simply as a soap, or in conjunction with a lotion, is often of special value:--

[Rx] Sulphur, praecip., .................... [dram]iv Saponis viridis, ..................... [dram]xii. M.

After the disease is apparently cured, an occasional remedial application should be made for several months, in order to guard against the possibility of a relapse.

Erythrasma.

Describe erythrasma.

Erythrasma is an extremely rare disease, due to the presence and growth in the epidermic structures of the vegetable parasite--the _microsporon minutissimum_. It is characterized by small and large, slightly furfuraceous, reddish-yellow or reddish-brown patches, occurring usually on warm and moist parts, such as the axillary, inguinal, a.n.a.l and genitocrural regions. It is slowly progressive and persistent, but is without disturbing symptoms other than occasional slight itching.

[Ill.u.s.tration: Fig. 75.

Microsporon Minutissimum x 1000. (_After Riehl._)]

Treatment, which is rapidly effective, is the same as that employed in tinea versicolor.

Dhobie Itch.

Dhobie itch is a name used in certain tropical countries to designate a somewhat peculiar itching eruption of the genitocrural and axillary regions, and by some also a similar eruption about the feet. It consists of a dermat.i.tis of variable degree, usually with a festooned, irregular border, with considerable itching. It is believed that such cases are variously due to the trichophyton of ringworm, to the microsporon furfur of tinea versicolor, to the microsporon minutissimus of erythrasma, and to other parasites.

Actinomycosis.

Describe actinomycosis.

Actinomycosis of the skin is an affection due to the ray fungus, and characterized by a sluggish, red, nodular, or lumpy infiltration, usually with a tendency to break down and form sinuses. The affection may involve almost any part, but its most common site is about the jaw, neck, and face. As a rule, the first evidence is a hard subcutaneous swelling or infiltration, which may increase slightly or considerably.

The overlying skin gradually becomes of a sluggish or dark-red color.

Softening ensues, and the diseased area breaks down at one or more points, from which there oozes a discharge of a sero-purulent, purulent, or sanguinolent character. In this discharge can be usually noted minute, friable, yellowish or yellowish-gray bodies representing conglomerate collections of the causative fungus.

The course of the malady is commonly slow and insidious. Unless systemic pyemic infection occurs or the fungus elements find their way to the deeper organs or structures the general health remains apparently undisturbed.

What is the treatment?

The administration of moderate to large doses of pota.s.sium iodide, conjointly with curetting or excision of the diseased ma.s.s. Local applications of iodine solution can also be tried.

Blastomycetic Dermat.i.tis.

What do you understand by blastomycetic dermat.i.tis?

Blastomycetic dermat.i.tis is a rare disease beginning usually as a small papule or nodule, enlarging slowly, breaking down and developing into a verrucous or papillomatous-looking area, similar in appearance to tuberculosis cutis verrucosa. A muco-purulent or purulent secretion can visually be pressed out from between the papillomatous elevations. It may also present the appearance of a serpiginous lupus vulgaris or syphiloderm. As a rule it is slow in its course. Furuncular or abscess-like formations may develop, usually from secondary infection.

The disease is due to the invasion of the cutaneous tissues by the blastomyces.

[Ill.u.s.tration: Blastomycetic dermat.i.tis.]

Treatment consists in administration of moderate to large doses of pota.s.sium iodide, and in the employment of antiseptic and parasiticide applications; usually, however, radical treatment, such as employed in lupus vulgaris, may be necessary.

Scabies.

(_Synonym:_ The Itch.)

What is scabies?

Scabies, or itch, is a contagious animal-parasitic disease characterized by a multiform eruption of a somewhat peculiar distribution, attended by intense itching.

Describe the symptoms of scabies.

The penetration and presence of the parasites within the cutaneous structures besides often giving rise to several or more complete or imperfectly formed _burrows_, excite varying degrees of irritation, and in consequence the formation of vesicles, papules and pustules, accompanied with more or less intense itching. Secondarily, crusting, and at times a mild or severe grade of dermat.i.tis, may be brought about.

The parasite seeks preferably tender and protected situations, as between the fingers, on the wrists, especially the flexor surface, in the folds of the axilla, on the abdomen, about the a.n.a.l fissure, about the genitalia, and in females also about the nipples, and hence the eruption is most abundant about these regions. The inside of the thighs and the feet are also attacked, as, indeed, may be almost every portion of the body. The scalp and face are not involved; exceptionally, however, these parts are invaded in infants and young children.

Is the grade of cutaneous irritation the same in all cases of scabies?

No; in those of great cutaneous irritability, especially in children, the skin being more tender, the type of the eruption is usually much more inflammatory. In those predisposed a true eczema may arise, and then, in addition to the characteristic lesions of scabies, eczematous symptoms are superadded; in long-persistent cases, indeed, the burrows and other consequent lesions may be more or less completely masked by the eczematous inflammation, and the true nature of the disease be greatly obscured.

What do you mean by burrows?

Burrows, or _cuniculi_, are tortuous, straight or zigzag, dotted, slightly elevated, dark-gray or blackish thread-like linear formations, varying in length from an eighth to a half an inch.