Tinea Trichophytina.
Tinea trichophytina, or ringworm, is a contagious vegetable parasitic disease, due to the trichophyton, its clinical characters varying according to the part invaded. It is a common disease, more frequent in children than in adults, and is met with to a varying extent in all countries. It is contagious, but individuals vary as regards susceptibility. The fungus (the trichophyton) consists of spores and mycelium. The latter consists of long, slender, delicate, sharply-contoured, pale-grayish, straight or crooked, branching, ribbon-like threads, containing spores and granules. They are remarkable for their length. The spores are round, small, highly refractive, grayish or pale-greenish bodies, and are either single or arranged in rows, which may be isolated or joined to mycelium. The appearances of the disease, and to a certain extent its treatment, are so different when affecting the general surface, the scalp or the bearded region that separate descriptions are called for. When seated upon the general surface the disease is commonly known as tinea circinata (tinea trichophytina corporis); on the scalp, tinea tonsurans (tinea trichophytina capitis); on the bearded region, tinea sycosis (tinea trichophytina barbæ).
TINEA CIRCINATA, or ringworm of the body, is characterized by one or more circular or irregularly-shaped, variously-sized, inflammatory, slightly vesicular or squamous patches. It usually begins by the formation of one or more roundish, slightly-elevated, sharply-limited, somewhat scaly, hyperæmic spots, which in some cases show minute papules or vesicles, especially about the periphery. As the process advances, usually in the course of a few days, the inflammation is more marked and the scaliness increased. The patches assume, as a rule, a distinctly annular character, and as they grow by extending peripherally, their centres clear up, so that when fully developed they are usually about an inch in diameter, and consist of a more or less normal central area, then an intermediate pale-reddish scaly portion, and the red, elevated, and scaly or papulo-vesicular or vesicular border defined against the healthy skin. In rare instances vesico-pustules may form. There may be one, several, or many patches present, but as a rule they are not numerous. After attaining a certain size they may remain stationary for a short time or may begin to disappear spontaneously. Where two or more are in close proximity, they may increase in size, gradually coalesce, and form gyrate or irregularly-shaped lesions. At times, instead of the typical annular patches, the disease may appear in the form of disseminated, small, reddish, slightly scaly, ill-defined spots, which may appear and disappear rapidly, the patient rarely being free of lesions. Although any portion of the general surface may be invaded, there are certain regions of predilection, as the face, neck, and backs of the hands. It is commoner in children than in adults.
Involving surfaces that are in close contact, as the axillæ, between the buttocks, and the inner surfaces of the thighs, it tends to spread extensively, is more inflammatory, and often proves rebellious to treatment. Invading these parts, the condition, under the impression that it was an eczema, was described by Hebra as eczema marginatum. It is most common, however, about the thighs, and seated here is termed tinea circinata cruris. It begins usually in the same manner as ringworm on other regions, but on account of the heat, moisture, and friction of the parts its characters become changed. The patch becomes inflamed, slightly elevated, coalescing with similar patches, until the greater part of the inner surface of the thighs and buttocks may be involved. The groins and mons veneris may also be invaded. When fully developed it is characterized by extensive, irregularly-shaped, inflammatory patches, with at times a slightly moist surface, and is usually well defined against the surrounding healthy skin by a more or less raised border, which may show papules or vesicles. Sometimes beyond the general area involved may be seen more or less typical ringworm patches. As met with in this country, it is usually mild in character. In Southern Europe it is encountered more frequently, is of a severer type, and is often intractable. It is met with usually in adults. Relapses are not uncommon.
The course of ringworm of the general surface may be acute or chronic. It may disappear in a few weeks, or, on the other hand, may continue indefinitely. As commonly met with in this country, it is, as a rule, readily responsive to treatment. It is frequently seen in association with ringworm of the scalp. Itching in variable degree is usually present. Invading the nails, the affection is designated tinea trichophytina unguium. These structures become dry, opaque, dirty white or yellowish, thickened, of irregular shape, bent, soft, or brittle and laminated, the changes taking place especially about the free border. The nails of the toes are seldom affected. As a rule, not more than two or three of the finger-nails are attacked. It is commonly associated with chronic ringworm on other parts of the body.
The fungus (trichophyton) in tinea circinata has its seat in the epidermis, especially in the corneous layer. The first effect of its invasion is hyperæmia, subsequently inflammation, usually mild in character, with more or less scaling. A microscopical examination, with a power of two to five hundred diameters, of scales from the periphery of a patch, moistened with liquor potassæ, will show both mycelium and spores, the latter comparatively few in number. In fact, the fungus in ringworm of the body is rarely to be found in abundance. In tinea trichophytina unguium the substance of the nail is invaded, scrapings of which will show the fungus, usually the mycelium, generally but few spores being present.
The affection is to be recognized by its peculiar clinical features, and, if necessary, by means of the microscope. This instrument should always be employed in cases of doubt. At times it bears resemblance to eczema and seborrhoea, and to psoriasis. From eczema it may be distinguished by its circular or annular form, its sharply-defined margins, its tendency to clear up in the centre, its slight desquamation, and its history and course; the itching is usually less marked than in eczema. Seborrhoea, when occurring on the chest and back, often consists of circular patches similar in general features to ringworm, but the scales are greasy, and are seated upon non-inflamed skin; the scaliness of ringworm is the result of inflammation, while that of seborrhoea consists of dried sebaceous matter. Moreover, in the latter affection the sebaceous follicular openings are perceptibly enlarged, and are indicative of the nature of the disease. In psoriasis at times the patches clear up in the centre, and in such instances a mistake in diagnosis might occur. The scaliness of psoriasis, however, is always a marked feature; it is usually insignificant in ringworm. Moreover, the characters of the scales are different. Occasionally the circinate tubercular syphiloderm has been confounded with ringworm, but the nature of the patch in the former disease, consisting of an irregular and incomplete ring of elevated tubercles or infiltrations, with, at times, ulceration, is so entirely different from the latter affection that an error should not occur. It can scarcely be confounded with favus if the peculiar yellowish, cup-shaped crusts of that disease are kept in mind; the clinical features of the two affections are also in other respects dissimilar.
The treatment consists in the application of the milder parasiticides, the disease rarely proving obstinate. In exceptional cases, where the affection is persistent, it will sometimes be found that the general nutrition is below the standard; and in such instances constitutional remedies of a tonic nature, as cod-liver oil, iron, quinine, and arsenic, are serviceable. In children the skin is delicate and strong remedies are not well borne; nor are they, as a rule, necessary. The parts should be first washed with soap and water, and then the remedial applications made; the lotion or ointment should be applied two or three times daily. If a lotion, it should be dabbed on thoroughly; if an ointment, it should be thoroughly rubbed into the patches. The sulphite or hyposulphite of sodium, in lotion or ointment form, a drachm to the ounce; sulphurous acid, full strength or diluted; ammoniated mercury, thirty to sixty grains to the ounce of lard or vaseline; corrosive sublimate, two to four grains to an ounce of alcohol or water; an ointment of sulphur, a drachm or two to the ounce; tar ointment, a drachm or two to the ounce; carbolic acid, ten to thirty grains to the ounce of water or lard,—are all parasiticides of value which may be employed in this disease. In obstinate cases chrysarobin, five to thirty grains to the ounce of lard, may be cautiously used, or it may be applied in collodion or gutta-percha solution, 5 to 10 per cent. strength. In tinea circinata cruris applications such as the above, but stronger, are serviceable. R. W. Taylor speaks well of a solution of corrosive sublimate in tincture of benzoin, two to four grains to the ounce, painted over the parts. The chrysarobin ointment or solution already mentioned may also be especially referred to. Hebra's modification of Wilkinson's ointment (see Scabies for formula) is useful in these cases. In tinea trichophytina unguium the nail should be pared or scraped, and one of the parasiticides applied.
TINEA TONSURANS.—Tinea tonsurans, or ringworm of the scalp, is characterized by circular or irregularly-shaped, variously-sized, scaly, more or less bald patches, showing the hair to be diseased and usually broken off close to the scalp. It is met with in children, especially in those under the age of twelve years; it is rarely seen after puberty. It begins as one or more small, round, erythematous, scaly spots, which may be minutely papulo-vesicular or vesicular about the periphery. Soon by peripheral growth typical circular patches of various sizes are formed, averaging about an inch in diameter. More or less itching is usually complained of. A typical patch is circumscribed, slightly elevated, reddish, grayish or slate-colored, with more or less scaling, usually thin or bran-like in character, with the hairs broken off close to the scalp. The color varies with the complexion of the individual; in marked blondes it has usually an inflammatory tint, while in those of dark hair and skin it is bluish-gray or the color of slate. The hairs on the affected areas are involved early in the disease, becoming lustreless, dry, brittle, twisted, breaking off close to the skin, with their free extremities ragged and uneven, having a gnawed or nibbled look. They are easily extracted, or often break off within the follicles, appearing then as blackish dots. A variable degree of baldness occurs, which, however, is rarely permanent. In some instances the patch is non-inflammatory and free of scales, the loss of hair, which is more or less complete, taking place rapidly, such cases bearing resemblance to alopecia areata. As a rule, several patches varying in duration and size are present. They may remain discrete, or coalesce and form irregular areas. The vertex and parietal regions are favorite localities, although any region of the scalp may be invaded. It is not uncommon to see patches of the disease on the non-hairy portions of the body at the same time.