Heat and cold, sharp, biting winds, excessive use of water, strong soaps, vaccination, dyes and dyestuffs, chemical irritants, and the like. There is a growing belief that some cases presenting eczematous aspects are probably parasitic in origin. In fact, some observers hold to the microbic view of all cases of eczema. Contact with the rhus plants, while producing a peculiar dermatitis, usually running an acute course terminating in recovery, may, in those predisposed, provoke a veritable and persistent eczema. In fact, in our examination as to causes in a given case, especially of the hands and face, all possible exciting factors should be inquired into, such as the handling of plants, chemicals, dyes, etc.
Fig. 24.
Eczema of Face.
Is eczema contagious?
No. The acceptance of a parasitic cause for the disease, however, necessarily carries with it the possibility of contagiousness under favoring conditions. Such is not supported, however, by practical experience.
What is the pathology?
The process is an inflammatory one, characterized in all cases by hyperæmia and exudation, varying in degree according to the intensity and duration of the disease. The rete and papillary layer are especially involved, although in severe and chronic cases the lower part of the corium and even the subcutaneous tissue may share in the process.
Do the cutaneous manifestations of the eruptive fevers bear resemblance to the erythematous type of eczema?
Scarlatina and erysipelas may, to a slight extent, but the presence or absence of febrile and other constitutional symptoms will usually serve to differentiate.