A system of practical medicine. By American authors. Vol. 4

by Unknown

The number of patches varies; as a rule, a half dozen or more are present; in other cases they may be numerous. They show more or less furfuraceous scaling, varying with the amount of perspiration and the frequency with which the parts are washed. The scaling, even when it is insignificant or when the patches are apparently smooth, may be easily detected by scratching or scraping the surface. Slight itching is ordinarily present, especially when the parts are unusually warm; it is rarely marked. The color is usually a pale or brownish yellow. In sensitive skins at times the affection causes more or less hyperæmia, and the spots have a reddish hue. The course of the disease is variable, sometimes spreading rapidly, while in most cases its progress is slow. It is, as a rule, persistent, existing years. Relapses are not uncommon.

The cause of the disease is the vegetable fungus, the microsporon furfur. It invades the superficial portion of the epidermis. The affection is but slightly contagious. Those between the ages of twenty and forty, of either sex indifferently, are most frequently the subjects of the disease; it rarely if ever occurs in children or in elderly people. It is commonly observed in those whose nutrition is below the standard, especially in persons having pulmonary phthisis. It is a common affection, and occurs, in varying proportions, in all parts of the world. Scrapings or scales moistened with liquor potassæ may be examined with a power of three to five hundred diameters, and the peculiar features of the fungus well brought out, as the fungus exists in abundance. It consists of mycelium and spores, the former appearing as short, slender, variously-sized, straight or curved, twisted, wavy, or angular threads, crossing one another in all directions. In appearance they are homogeneous or granular, and often contain spores, especially about the joints. The spores are ovalish or round, sharply contoured, small in size, with a nucleus and slightly granular plasma. They show a marked tendency to aggregate and form groups—an arrangement which is characteristic of this fungus. The growth is found in every stage of development from mycelium to spores.

There should be no difficulty in recognizing the disease if its characters and distribution are kept in mind. In doubtful cases the microscope will prevent error. It is at times confounded with chloasma, vitiligo, and the macular syphilide. In chloasma, in which there is merely an increase of pigment in the rete, there is no scaling, the outlines are ill defined, and it is usually seen about the face—a region that is practically exempt in tinea versicolor. Moreover, the coloration in the parasitic disease is due to the fungus, which has its seat in the superficial epidermis and can be readily scraped off. With ordinary care it is impossible to mistake vitiligo for the disease in question. The macular syphiloderm is to be distinguished by attention to the distribution, character, and size of the lesions. Tinea versicolor is practically a disease of the trunk; the macular syphiloderm is usually distributed over the whole surface; and if it is the latter disease concomitant symptoms of syphilis are almost invariably present.

The disease is readily curable; any simple parasiticide properly and thoroughly applied will soon effect its removal. Lotions, as a rule, are to be preferred, inasmuch as they are more cleanly and more satisfactory. Washing the parts involved frequently with green soap (sapo viridis) and warm water is to be advised as an adjuvant, and will in some cases suffice to remove the disease. Alkaline baths, three or four ounces of carbonate of sodium or potassium to thirty gallons of water, are also useful. Various parasiticides are employed. Sulphite or hyposulphite of sodium, a drachm to the ounce; corrosive sublimate, two or four grains to the ounce of alcohol and water; sulphurous acid, pure or diluted; a saturated solution of boric acid; Vleminckx's solution, diluted with three to six parts of water,—are among the most useful. Sulphur and ammoniated mercury ointments, carbolic acid, ten to twenty grains to the ounce of lard, may be mentioned as serviceable. The frequency of application depends upon the extent and obstinacy of the disease, once or twice daily usually sufficing. After the disease is apparently cured treatment should be continued, although less actively, for a few weeks or a month, in order that a relapse may be avoided.

Scabies.

Scabies, or itch, is a contagious animal parasitic disease, due to the Sarcoptes scabiei, characterized by the formation of cuniculi, papules, vesicles, and pustules, followed by excoriations, crusts, and general cutaneous inflammation, and accompanied with itching. The amount of disturbance depends upon the duration of the disease and the sensitiveness of the skin. The itch mite (Acarus scabiei, Sarcoptes scabiei, or Sarcoptes hominis) through contagion finds its way upon the skin, and begins to burrow its way through the upper layers of the epidermis. The female only is found within the epidermis, the male, as generally supposed, never penetrating the skin. As the female burrows she lays a varying number of eggs, a dozen or more; by this time the burrow, or cuniculus, has usually attained its full length of several lines. It is to be seen as a narrow whitish or yellowish linear epidermic elevation, as a rule irregular and tortuous, and with a dotted or speckled look. It contains the female, its excrement, and a variable number of eggs. In a short time the ova are hatched, and the mites are rapidly multiplied. New burrows appear and are to be seen in all stages of development, and thus the disease progresses.

According to the sensitiveness of the skin will the lesions produced in consequence of the irritation of the mite vary. Usually, inflammatory points, papules, vesicles, pustules, and excoriations are to be seen scattered over the regions involved. The hands, especially the sides of the fingers, are almost invariably the parts first attacked, the mite gradually invading other parts of the body, as the anterior surfaces of the wrists, forearms, elbows, and arms, the axillary folds, about the mammæ in females, between the buttocks, about the penis, the inner sides of the thighs. The face and scalp are never invaded, except in infants. Itching is a marked symptom, usually worse at night. In well-advanced cases the secondary symptoms, such as papular elevations, vesicles, impetiginous and ecthymatous pustules, which are often torn by the scratching invoked, the crusts and excoriations of various characters, and a variable amount of cutaneous inflammation, with infiltration and pigmentation, taken together with the presence of burrows, constitute a clinical picture of the disease. In many cases the cuniculi are in a great measure obliterated by the scratching; their remains, however, may usually be detected. In persons with eczematous skin true eczema may be developed.

The disease is due solely to the presence of the itch mite. It is met with in persons of all ages and in every station of life, but for obvious reasons is more common and its ravages more marked among the poor. It is encountered in all parts of the world, but is especially frequent in the various European countries. In the United States it is comparatively infrequent, and is seen chiefly in the seaboard cities, and many of the cases can be traced to direct importation from abroad. It is markedly contagious. The Sarcoptes scabiei is almost microscopic in size, appearing as a yellowish-white rounded body. The male is but half the size of the female, and is rarely met with, apparently having no direct part in producing the cutaneous disturbance seen in the disease. The full-grown female, as may be determined by microscopical examination, is ovoid or crab-shaped, the dorsal surface convex and the ventral surface flattened, the back being studded with a varying number of short, thick spines and several long spike-shaped processes, all with their points directed backward. The head is small, rounded, or oval, without eyes, and closely set in the body, and is provided with palpi and mandibles. There are eight legs, four situated close to the head and four posteriorly. The entire parasite scarcely exceeds a fifth of a line in length. The female mite is to be looked for at the blind end of a burrow or at the roof of a vesicle.

Scabies when fully developed may usually be recognized without difficulty. The pathognomonic symptom is the presence of the parasites or the burrows. In the early stage cuniculi are not yet fully formed, but often the mite may be extracted from a recent vesicle. Burrows are usually most typically seen upon the sides of the fingers. The distribution of the eruption, however, is, in most cases, a sufficient basis for a diagnosis, the fingers, hands, flexor surface of the wrists, elbows, axillæ, buttocks, penis, mammæ in females, being especially invaded. It may be remembered also that the face and scalp, except in infants, are not involved. The multiform nature of the eruption is one of its prominent characteristics. It is a progressive disease. A history of contagion is often obtainable. It is to be distinguished from vesicular and pustular eczema and pediculosis. The more or less discrete vesicles and pustules of scabies, the localities affected, its progressive course, and the presence of burrows and a history of contagion will serve to differentiate from eczema. Pediculosis corporis involves the covered portions of the surface only, and the regions usually involved are different from those invaded in scabies. In scabies the hands are almost invariably the parts first and most markedly involved. The characters of the lesions are also different.

The disease yields rapidly to proper treatment. Various remedies are employed for the destruction of the parasite and its ova. The most common, and one that is thoroughly efficient, is sulphur. It is usually prescribed in ointment, one to four drachms to the ounce. In irritable skins, or where the secondary dermatitis is marked, the weaker proportions are advisable. A proportion of two drachms to the ounce is the average strength, and will be found suitable for the majority of cases. For children a drachm to the ounce is sufficiently strong; in these cases a half drachm of balsam of Peru may be added. This latter remedy is of itself a parasiticide. A compound sulphur ointment, known as Hebra's modification of Wilkinson's ointment, frequently employed abroad, is made up as follows: