16 TILBURY FOX';
A CLINICAL STUDY ON HYDROA.
BY THE LATE TILBURY FOX, M.D., F.R.C.P.
EDITF.D WITH NOTES BY T. COLCOTT FOX, B.A. (Cantab.), Physician to Saint George's and Saint James' Dispensary.
SECTION I.—INTRODUCTORY.
THE term Hydroa has of late come into use among certain dermatologists as one which is conveniently applicable to a special set of cases of vesicular or semi-buUous eruption which, clini- cally, need recognition as a distinct and separate class of cutaneous disorders.
That such a group exists is certain, the components of which do not truly answer in their main characters either to the exceptional development of an erythema, to herpes, or to pemphigus; but that the utmost uncertainty and haziness also is prevalent as to the exact components of the group, must be evident to any one who has read the divergent descriptions of hydroa to be found in books; or who has listened to the opinions expressed concerning the rarer and anom- alous instances of vesicular eruptions brought before societies ; or who is aware of the widely different teaching on the subject in the dermatological chairs in the various medical schools.
The object of this paper is the endeavor to remove some of the confused notions which exist generally regarding the nature and affinities of these unusual phases of vesicular or bullous eruptions, which may be designated by the term Hydroa, and to define their clinical characters with more precision than has been the case hitherto.
Bazin* was the first to attempt to define this group, as signifying an eruption of vesicular character, which he found a difficulty in associating with certain forms of erythema on the one hand, and with herpes and pemphigus on the other, — a difficulty which, guided by Bazin's admirable remarks, I long ago felt. Bazin considered the group hydroa one of the manifestations of a special "arthritic" diathesis, and hence his term "hydroa arthritique." He described an acute and two chronic phases of the disease, which he termed respectively (i) hydroa vesiculeux; (2) H. vacciniforme; and (3) H. bulleux. He says the disease is analogous to the herpes phlyc- tenodes of Willan, and is a herpes successif et chronique, which has not sufficiently attracted the attention of authors. The features common to the three phases are, that there is an eruption of vesicles or little bullre, of marked inequality in size, or, as he calls them in another place, "large vesicles," arranged in groups here and there, with intervals of healthy skin. This eruption has a special predilec-
- Lemons theoretiques et cliniques sur les Affections cutanees de Nature
arthritique et dartreuse, i860.
