An occasional form of the disease is that called pemphigus solitarius, where a single bleb rises on the hand or foot, often on one finger, and quickly attains a great size. Sometimes the bleb involves the whole of the hand. Mr. Naylor described a variety of pemphigus which he called " pomilholyx diutinus in children." This form begins like ordinary pem phigus as a small red spot, which becomes a bleb and rapidly enlarges. After the bladder has ruptured the sore still continues to spread, and be comes covered with a thin wrinkled crust with a narrow raised rim, the remains of the bleb. The disease appears to be a purely local one, and the general health is quite unaffected. Dr. E. Liveing has doubts if this af fection be a true pemphigus.
The sore of pemphigus, like other sores, may assume a gangrenous form in unhealthy, cachectic. children. The resulting condition is very much that already described as a consequence of gangrenous varicella (see page 49).
The duration of the disease is apt to be prolonged, and sometimes the eruption returns very rapidly after apparent cure. The nature of the affection can hardly be mistaken, for the large blebs or blisters surrounded by healthy skin are pathognomonic. Blebs are often seen in the course of other forms of skin disease, such as scabies, eczema, erysipelas, etc. In the latter malady the extensive reddened, brawny surface on which the bladder is seated will be a sufficient distinction. In the case of the two former complaints the characteristic appearances peculiar to these disorders will be observed. The bullous syphiloderm is distinguished from pemphigus by the presence of other signs of the constitutional disease. In infants bullous eruptions are commonly of syphilitic origin.
The best treatment for pemphigus is arsenic. The remedy should be given in full doses, for a child of six years and upwards will take doses as large as those usually prescribed for an adult. If the irritation and dis comfort of the skin and general nervous disturbance prevent sleep, opium is useful, more especially as in the opinion of experienced observers the drug has a direct curative influence upon the disease. It is especially serviceable in the early acute stage. The sores on the skin must be kept very clean and treated with some mild application, such as a lead lotion or zinc ointment. .
Ecthyniatous pustules are very common in early life. In children of all ages, irritation of the skin is very apt to be followed by the development of large flattened pustules seated on a broad base and surrounded by a red zone of inflammation. Their favourite seats are the face, hands, and feet. The subjects of the complaint are often under-nourished, and it is therefore very often seen amongst the children of the poor ; but in all ranks of life any derangement or other cause which determines a temporary re duction of strength appears to have a predisposing influence in inducing the eruption. Such children are usually pale and flabby, and in them any slight scratch may be followed by a festering sore which continues unhealed as long as the debility from which the patient is suffering re mains unrelieved. Quinine has a specific influence in removing this
troublesome affection. After the alkaloid has been taken for a few days or a week the pustules disappear, the sores heal, and the child is well. In all these cases the diet should be attended to and any error of feeding corrected. A little wine is often of service, and the child should have plenty of fresh air and exercise.
A mild form of psoriasis is met with in children. The eruption usually OMITS in the form of psoriasis guttata, the little patches being scattered about, not very thickly, on the trunk and limbs. The patches are usually small, of a pale red tint, and are more or less scaly on the surface. They may be attended with slight itching. Psoriasis is seldom obstinate at this period of life, and usually yields without difficulty to arsenical treatment. Sometimes, however, the perchloride of mercury seems to be more useful than arsenic. As a local application the unguentum picis, or a mild chrysophanic acid ointment (gr. x. to the ounce of lard), may be made use of.
The parasitic diseases of the skin will be described afterwards. In the present chapter reference may be made to the form of disease called alopecia areata, which is not unfrequently seen on the heads of children of five years of age and upwards. The disease is characterised by the loss of hair in spots on the scalp. At these spots the hair-bulbs atrophy, and the hairs, growing loose, are shed without undergoing any other alteration in structure. In this way bald patches are formed, in which the scalp is completely smooth, white, and hairless. At the circumference of the patch the hair grows thickly as on the unaffected parts of the head. The number of patches may be one or more, and they may spread so as to unite and almost denude the head of its hair. At one time the disease was thought to be parasitic, but it is now allowed by most pathologists to be a simple atrophy of the hair-bulb ; and the hairs examined microscopically are found to resemble in every respect those which are cast off in the natural process of decay.
The disease usually tends to spontaneous cure. The bald patches become eventually covered with a fine down which grows thicker and darker until at last the spot ceases to be recognised. In some cases the new hairs remain colourless and give a curiously variegated appearance to the head. In others the hair is only partially reproduced, so that in places the scalp may remain permanently bald.
The only treatment for this condition is energetic stimulation with irritating applications, such as tincture of iodine, cantharides, etc. Dr. Thin recommends sulphur ointment.
The above varieties of cutaneous eruption may be dismissed without further notice. There are, however, other forms of skin disease which from their frequency or importance require a more detailed description. The following chapters will therefore be devoted to the consideration of the erythemata, eczema, molluscum contagiosum, the parasitic diseases, and sclerema.