Non-Excoriated Eczematous Diseases-Skin Disorders

Impetigo often presents as a shallow, red erosion covered with crust. The presence of weeping, crusting, and pruritus allows the non bullous form of the disease to be morphologically placed within the group of eczematous diseases. Impetigo is identified by its location around the nose and mouth, by its rapid appearance and spread, by the presence of pus underneath the crust, and by its prompt response to antibacterial therapy. Other clues to correct diagnosis include history of contagion, paucity of inflammation compared with the magnitude of crusting, and recovery of streptococcal or staphylococcal bacteria Oil culture. The term infectious eczematoid dermatitis was originally used for those eczematous lesions that appeared ill the skin around infected, draining lesions. However, it is now apparent that this eczematization is due more to the macerating and irritating effect of the draining fluid than to any bacteria that it might contain. Thus the rash around an ileostomy (which drains sterile fluid) is similar in appearance to that around a colostomy (which drains fluid with a high bacterial count). Therefore, this process can be viewed as a variant of weak-irritant contact dermatitis; the term "infectious eczematoid dermatitis" is best left as an historical footnote in the annals of dermatology. The patches and plaques of perioral dermatitis are often covered with a small amount of yellow scale. As in seborrheic dermatitis, a disease to which it is related, the yellow is due to the exudation of small amounts of serum onto the surface of the skin. Minute pustules may stud the surface of the erythematous patches or plaques, and thus the condition is also considered . As the term "perioral" implies, this condition occurs on the lower half of the face. A characteristic feature is the presence of a narrow margin of normal skin that occurs between the lips and the beginning of the eruption. There are several types of sunlight-induced eczematous diseases. First, photosensitivity may be induced by internally administered medications such as the tetracyclines, phenothiazines, thiazide diuretics, sulfonamide antibiotics, and nalidixic acid. Second, photocontact dermatitis may occur in a small percentage of patients applying cosmetics containing musk ambrette, sunscreens containing para-raminobenzoic acid (PABA), PABA esters, cinnamates, or benzophenones; and in the past at least, soaps containing halogenated bacteriostatic agents. Third, chronic sun exposure occurring over years may result in the development of hundreds of small, closely set, slightly crusted actinic keratoses superimposed on an inflammatory background. This process can be considered conceptually as a form of actinic dermatitis. Finally, the photosensitivity eruption of systemic lupus erythematosus (the "butterfly eruption") is sometimes so intense it takes on an eczematous morphology in a sun-exposed distribution pattern.