Part 89

Yes; the upper part of the trunk, especially anteriorly, is the usual seat of the eruption, but in exceptional instances the neck, axillæ, the arms, the whole trunk, the genitocrural region and poplitea, and in rare cases even the lower part of the face, may become invaded.

#What course does tinea versicolor pursue?#

Persistent, but somewhat variable; as a rule, however, slowly progressive and lasting for years.

#To what is tinea versicolor due?#

To a vegetable fungus--the microsporon furfur.

The affection is tolerably common, and occurs in all parts of the world. With rare exceptions, it is a disease of adults, and while looked upon as contagious, must be so to an extremely slight degree.

#What is the pathology?#

The fungus, consisting of mycelium and spores, the latter showing a marked tendency to aggregate, invades the superficial portion of the epidermis.

#Is tinea versicolor readily diagnosticated?#

Yes; if the color, peculiar characters and distribution of the eruption are kept in mind.

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 scrapings are taken from a patch, moistened with liquor potassæ, 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.

#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:--

Sulphur, præcip., .................... iv Saponis viridis, ..................... 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, anal and genitocrural regions. It is slowly progressive and persistent, but is without disturbing symptoms other than occasional slight itching.

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 dermatitis 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.