On the psoriasis or lepra / by George Gaskoin.

Date:
1875
Catalogue details

Licence: Public Domain Mark

Credit: On the psoriasis or lepra / by George Gaskoin. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    24/258 (page 4)
    exfoliation of skin^ but only in small and ragged bits, and not in one large piece as seen in Eczema exfoliativa, and it extends no deeper than the cuticle. As a general rule of some practical utility, we may say, no scale, no psoriasis ; for instance, with localised erythema, if it lasts any time it is wont to cast and also to heap up some scale, and then it is ill distinguished from psoriasis; they are parted by no hard and fast line, but an erythema devoid of scale we may hesitate to call psoriasis ; this could only be excused and justified by certain attendant conditions. Just so with lupus in its early stage; many times with great difficulty it will be divided from psoriasis; true that lupus with a dry white’ scale will mostly lie in part beneath the superficies, and nearly always it betrays itself in a scar. The complaint called Ichthyosis, the fish-skin disease, was originally con- founded with psoriasis, and this latter, or rather lepra, was always described as exhibiting scales like those of a fish. The diseases, in fact, are very different, though having some points of analogy, especially in their causation. The scale in both is nacreous and opaque, but in neither of the two does it show little diversity; and the popular idea in the way of eomparison connects the exuviie of psoriasis rather with plumage of birds than with the scale of fish or reptile. But using the word scale as a general term, including in its meaning all of scurf, fluff, lamina, or crust, one may say it is indeed the true epidermic scale diseased, that is to say, altered or perverted in its formation or nutrition, and in such sense it differs wholly from the scale of eczema, which is scarce other than the dry residuum of serous exudation; and especially these scales come early in psoriasis, and, as one may say, at the very first, whereas in eczema they come after and succeed to a serous discharge. Besides being free from moisture compared with eczema, the scale of psoriasis is more thick and opaque and smaller in size; in this way it is well distinguished from the thin, flat, large semitrans- parent scale of the latter disease. Than the scale or scurf of pityriasis and lichen it is also more thick and gross. In these distinctions we must use discretion rather than