Definition And Description

Ichthyosis is an affection characterized by an excessive development of the horny layer of the skin. As a rule it first manifests itself within a few months after birth by a preternatural dryness and roughness of the integument. This gradually increases until it is plainly seen that a marked change has occurred in the epidermis, which slowly thickens until at last the entire skin, or a portion of it, is found covered with a thick scaly coating adhering firmly, but divided i cracks and fissures into small, irregular areas. On removal of these thickened masses we do not find much change in the color of the skin, but simply a dry, sometimes slightly reddened surface, marked by exaggeration of the normal skin-lines.

In the beginning, when merely dry, and with but very moderate epidermic hypertrophy, the prevailing color of the skin, in cleanly persons, is light, although there appears to be some increase of pigment in the cells of the rete. Later, as Ichthyosis advances, the color of the surface changes, becoming tawny, dark, and at last almost black. This is due not so much to pigmentary discoloration of the skin proper, as to accumulation of dust and dirt among the epidermic scales. A remarkable pecu-liarity of this disease is the diminution or absence of perspiration. In many cases, this function is merely diminished, in others it appears to be-almost totally absent. This is undoubtedly due either to congenital absence of many of the sudoriparous glands, or to their faulty development or. early atrophy. In one case that I carefully examined, it was impossible to. detect, with an amplifying power of twenty diameters, any trace of the little depressions in the papillary ridges of the palmar surfaces of the hands and fingers, which correspond to the mouths of the sudoriparous follicles, and are so distinctly visible in the normal skin. At most, minute points of pearly lustre, not depressed, were observed in the situ-ations where the sweat-tubes should have opened. Upon the finger-tips alone were found a few normal tubes capable of properly discharging their function.

Course

The course of Ichthyosis is progressive, a spontaneous cure rarely if ever occurring.

Diagnosis

In advanced eases the diagnosis is not difficult, as the features of the disease are so well marked and sharply defined. The only affections that it at all resembles are Psoriasis, Pityriasis, and Xeroderma. In Psoriasis we find the eruption more patchy, and learn from the history that it developed from numerous small isolated foci. In Ichthyosis, on the other hand, the eruption is more diffuse, and although more marked in some situations than in others it never exhibits the sharpcircumscription met with in psoriasis. When the scales of psoriasis are removed, we find that they reposed on an infiltrated base to which they were firmly at-1 tached. The attachment is usually so close that slight oozing of blood follows its separation. This is not the case in Ichthyosis. Mild cases may sometimes resemble pityriasis at first glance, but in this latter affection there is a free furfuraceous desquamation not met with in the former.

Xeroderma simply means dry skin, and the name has improperly been applied to mild cases, or early stages of Ichthyosis. It should be reserved as the name of a condition or symptom only, and not as the name of a distinct disease. Conditions are not unfrequently met with for which the term may be appropriately employed, but which are not, and will not become, genuine Ichthyosis.

Prognosis

The prognosis of this affection is always grave. I am not aware that it is in any way prejudicial to life, but it rarely if ever disappears or is radically cured. The most that the patient has a right to expect is temporary amelioration.

Etiology

We know that in many cases the affection is hereditary and runs in families; beyond this its etiology is obscure.

Treatment

Treatment is wholly palliative. A perfect cure may generally be considered out of the question with our present means of treatment, and the most that we can hope to do is to ameliorate the patient's condition and to free him, to a greater or less extent, from its inconveniences. The first indication is to remove the thick masses of epidermic accumulation. The most prompt change that I have ever seen in this respect followed the use of daily drachm doses of fluid extract of Jaborandi. In two weeks the patient's skin was perfectly free from scales, was almost as soft as in health, and was only distinguishable from the normal condition by the exaggeration of the skin lines. How long this beneficial change continued I do not know, as the patient was shortly after lost sight of.

Lombroso reports a case of Ichthyosis cured by the daily administration of thirty grains of Ustilago maidis continued for four months, the treatment being suspended for one or two days in each week. The physiological action of the drug readily explains this effect. Although the result in these cases was unmistakable, I question whether it is prudent or right to continue either of these drugs for any great length of time.

Our main reliance, then, will be on local treatment. This may be initiated by a wet-pack administered as follows: The pack is prepared by placing four or five thick double blankets on the floor or bed. A cotton sheet is then wrung out in hot water and laid upon the blankets. The patient, in a nude condition, lies upon this, and the sheet and blankets are then wrapped snugly around him and retained in position with straps. The head alone protrudes and is supported by a suitable pillow. In this uncomfortable position the patient remains for two or three hours or more if he be not too seriously incommoded by his close quarters. The effect of the pack is to promote the exhalation of fluid from the surface of the skin, which macerates and loosens the scales. After the pack is over, the surface is dried and thoroughly anointed with some bland oil - purified cocoa-nut oil being the nicest application of the sort that I know of. The following day the pack is repeated in the same manner, and if necessary a third is taken. After this a thorough scrubbing with warm water, an alkaline soap, and a suitable brush will remove most if not all of the scales, leaving the skin comparatively smooth, but red and somewhat sore. Emollients should now be employed daily, and, if circumstances permit, a thorough inunction night and morning, or at least once a day, will do much to retard the re-establishment of the affection.