CHAPTER XLVIII.

DISEASES OF THE SKIN.

THE skin diseases of children are so numerous, and the literature of dermatology is so extensive, that the subject does not readily lend itself to a manual which treats of general medicine. I must, however, refer shortly to those more common affections which are of every-day occurrence, and to some few of the rarer conditions such as I have met with personally. A fuller treatment of the subject will not be necessary, considering the many excellent manuals that have been written of recent years.

As a preliminary, let me say that perhaps there is no organ of greater importance than the skin in childhood. It is in many cases a most sensitive index of inefficient working elsewhere; its suggestions as to constitutional peculiarities are often of the utmost value to the physician; when not properly cared for it readily goes wrong; and rough handling is quickly resented.. Its very activity is a source of danger if it be neglected, and many of the diseases of the skin in infant life are directly chargeable to neglect. Therefore, as a general principle, it is of the first importance to attend to scrupulous cleanliness. A good bath once a day is not too much for any child, and a bath night and morning should be given to young children. Most children perspire readily and excessively, particularly during sleep, and retained perspiration about the neck or in the groin, etc., produces first miliaria, and then intertrigo. Plenty of bathing and the use of the sanitary rose powder, in such parts as are liable to retain the secretions, will no doubt avert many a

case of what would otherwise prove a troublesome eczema intertrigo.

Warmth is another essential. Custom has prescribed that young children shall wear low dresses, short sleeves, petticoats, and no covering at all for the lower part of the abdomen and thighs, save a pair of linen drawers. This is a custom framed upon a weakest-goes-to-the-wall principle, which is opposed to the very raison d'être of medicine. Children's clothing is to be light and loose and warm. The method of accomplishment of these aims hardly needs a more detailed statement.

The more common affections of the skin are: Lichenoften called strophulus or lichen urticatus, from its almost inseperable connection with urticaria-eczema, impetigo, ecthyma, furuncular eruptions, herpes of all patterns, erythema likewise, psoriasis, tinea, alopecia, and molluscum contagiosum.

Of rarer occurrence are pemphigus, ichthyosis, lupus, keloid, erysipelas, scleroderma, xanthelasma, and favus.

Lichen urticatus, or strophulus, the red gum and white gum sometimes talked of, occurs chiefly from the age of five or six months onwards through the period of dentition. It is not unusual from two to four years, but its history may then be traced from a much earlier date; and even in older children, of eight, nine, or ten, a persistent lichen urticatus is occasionally met with. As seen in infancy, it occurs as rather sharply raised, whitish, rounded papules of a peculiarly hard or shotty feel, and often with a translucent centre, looking like a vesicle, but from which no fluid comes when pricked. The forearms, legs, and trunk are its favorite sites. It is very irritable, and associated often with urticaria, and for this reason the appearances vary, the characteristic papules becoming lost in wheals or changed into a number of bleeding or crusted points, from the excoriation produced

by scratching. Closely allied to this disease and to urticaria. is another, which has been called urticaria pigmentosa, or xanthelasmoidea, in which the trunk more particularly becomes covered with yellowish-brown blotches, the skin at the affected spot being raised and thick, like soft leather. Urticaria wheals are frequently seen about the body, and the history is often that the pigmented thickenings have begun as such-a fact as to the truth of which I have on more than one occasion satisfied myself. This disease was first described by Dr. Tilbury Fox as xanthelasmoidea, and a good many cases have since then been recorded. Dr. Colcott Fox has given a careful summary of all these,* and in addition has added important information on two points -first, he shows that the disease tends to disappear as the child grows up; and secondly, that the microscopical structure of the affected tissue is that of a wheal.

It is important to recognize in all these three affections that the difficulties of treatment lie less in the actual structural changes in the skin than in the fact that all these children have what Hutchinson calls a pruriginous skin. The subjects of urticaria pigmentosa have, not only a pruriginous skin but, also, as some cases of pemphigus, a peculiar tendency to the deposition of pigment in the skin. It is the constitutional element, if it may be called so, which allows of lichen, while some slight disturbance is the immediate provocative. Most often this is gastric disturbance or indigestion during dentition; sometimes it is the irritation of flea-bites; sometimes, again, as Hutchinson suggests, a varicella or some other exanthem. Hutchinson distinguishes between a prurigo due to varicella and that due to other causes, by the former being vesicular the latter not; but I cannot think that this distinction is of much service. Some

* "Trans. Med. Chir. Soc.," vol. lxvi.

exceedingly practical and valuable remarks, however, are made concerning the production of a pruriginous skin by eruptions of any chronicity, for all must be familiar with the fact that to scratch an itching spot is not only to make the spot more irritable, but also to extend the actual area from which the abnormal sensation is transmitted. It is easy thus to make the body itch all over; and this condition begets a pruriginous habit of skin which is quite out of proportion to the external cause.

Treatment.-Lichen urticatus is very obstinate. It and all three affections in this group are for the most part best treated by the strictest attention to the diet; but it is in many cases very difficult to say exactly in what element the cause of indigestion lies. Some children are said to be worse when eating sugar, some when they have taken too much milk; but I must confess to having been unable to reduce a not inconsiderable experience into concrete and dogmatic statements.

Having already given full space to diet, I shall only say that it will require careful scrutiny and probably modification according to the rules already detailed. Next in importance comes the necessity to deprive the surface as far as possible of all excuse for itching. This may be done both by external and internal means. Externally, the most scrupulous attention is to be paid to cleanliness. The skin is to be bathed frequently; the linen is to be changed frequently to ensure the absence of such pests as fleas; and in hospital out-patients scabies and pediculi must be examined for and treated if present. The nature of the clothing next the skin must also be examined. Some people are unable to wear flannel, or particular kinds of flannel, merino, etc., and dyed flannels are sometimes in use which may account for external irritation. The itching of the papules may be mitigated by gently rubbing over them and the affected skin

a lotion of bicarbonate of sodium, glycerine, and elder-flower or rose-water (F. 46), or a lotion of corrosive sublimate; half a grain to each ounce is sometimes effective (F. 47). Borax and glycerine may be used for the same purpose, or the skin may be oiled with vaseline or carbolic oil (1 to 40). Hutchinson recommends a solution of the liquor carbonis detergens (one part to four or five of water).

For the more chronic cases, a tar bath may be given, by adding the liquor carbonis detergens to water; or sulphur baths are useful—a tablespoonful of sulphur, or more, to a bath.

For internal administration in the acute stages, bicarbonate of sodium or potassium may be given, or some fluid magnesia. Either of the F. 7-11 will answer the purpose.

For older children, quinine in full doses, or cod-liver oil, seems to be of most service. I think, also, that the confection of sulphur and euonymin are of value in regulating the bowels and stimulating the liver.

Acute Urticaria is far less common than the chronic conditions just described. It is readily recognized when the wheals are out, unless, as is sometimes the case, these are exchanged for a more or less general œdema, when the face becomes swollen, like the visage of a child with pertussis, and the subcutaneous tissues of the extremities are rendered somewhat brawny. When the wheals are not out, there may be also a difficulty, very little remaining but small red papules, with perhaps when the itching has been severe a subdued ecchymosis or dusky condition of the skin.

Acute urticaria is certainly due immediately to errors in diet, though it is not unlikely that idiosyncracy may be the remote cause. It is to be treated by attention to the diet, and usually some alkali, as in F. 8 or 11, is all that is necessary. To allay the severe itching, bicarbonate of sodium,