Diagnosis of eczema is based mostly on the history and physical examination. In uncertain cases, skin biopsy may be taken for a histopathologic diagnosis of<unk> . Those with eczema may be especially prone to misdiagnosis of food allergies. Patch tests are used in the diagnosis of allergic contact<unk> . Classification The term eczema refers to a set of clinical characteristics. Classification of the underlying diseases has been haphazard with numerous different classification systems, and many synonyms being used to describe the same condition. A type of<unk>  may be described by location (e.g., hand eczema), by specific appearance (eczema craquele or discoid) or by possible cause (varicose eczema). Further adding to the confusion, many sources use the term eczema interchangeably for the most common type: atopic<unk> . The European Academy of Allergology and Clinical Immunology (EAACI) published a position paper in 2001, which simplifies the nomenclature of allergy-related diseases, including atopic and allergic contact eczemas. Non-allergic eczemas are not affected by this proposal. Histopathologic classification By histopathology, superficial<unk>  (in the epidermis, papillary dermis, and superficial vascular plexus) can basically be classified into either of the following groups: * Vesiculobullous lesions * Pustular dermatosis * Non vesicullobullous, non-pustular :*With epidermal changes :*Without epidermal changes. These characteristically have a superficial perivascular inflammatory infiltrate and can be classified by type of cell infiltrate: ::*Lymphocytic (most common) ::*Lymphoeosinophilic ::*Lymphoplasmacytic ::*Mast cell ::*Lymphohistiocytic ::*Neutrophilic Terminology There are several types of<unk>  including atopic<unk> , contact<unk> , stasis<unk>  and seborrhoeic<unk> . Many authors use the terms<unk>  and eczema synonymously, and various dictionaries that treat the terms as differentiable nonetheless do not provide explicit criteria for differentiating them, as the aspects of inflammation, pruritus, and either exogenous or endogenous provoking agent all can apply to either term, and thus autoimmune components are not excluded from either. Others use the term eczema to specifically mean atopic<unk> . Atopic<unk>  is also known as atopic eczema. In some languages,<unk>  and eczema mean the same thing, while in other languages<unk>  implies an acute condition and eczema a chronic one. Common types Diagnosis of types may be indicated by codes defined according to International Statistical Classification of Diseases and Related Health Problems (ICD). Atopic Atopic<unk>  is an allergic disease believed to have a hereditary component and often runs in families whose members have asthma. Itchy rash is particularly noticeable on the head and scalp, neck, inside of elbows, behind knees, and buttocks. It is very common in developed countries and rising. Irritant contact<unk>  is sometimes misdiagnosed as atopic<unk> . Stress can cause atopic<unk>  to worsen. Contact Contact<unk>  is of two types: allergic (resulting from a delayed reaction to an allergen, such as poison ivy, nickel, or Balsam of Peru), and irritant (resulting from direct reaction to a detergent, such as sodium lauryl sulfate, for example). Some substances act both as allergen and irritants (wet cement, for example). Other substances cause a problem after sunlight exposure, bringing on phototoxic<unk> . About three-quarters of cases of contact eczema are of the irritant type, which is the most common occupational skin disease. Contact eczema is curable, provided the offending substance can be avoided and its traces removed from one's environment. (ICD-10 L23; L24; L56.1; L56.0) Seborrhoeic Seborrhoeic<unk>  or seborrheic<unk>  ("cradle cap" in infants) is a condition sometimes classified as a form of eczema that is closely related to dandruff. It causes dry or greasy peeling of the scalp, eyebrows, and face, and sometimes trunk. In newborns, it causes a thick, yellow, crusty scalp rash called cradle cap, which seems related to lack of biotin and is often curable. (ICD-10 L21; L21.0) Less common types Dyshidrosis Dyshidrosis (dyshidrotic eczema, pompholyx, vesicular palmoplantar<unk>  only occurs on palms, soles, and sides of fingers and toes. Tiny opaque bumps called vesicles, thickening, and cracks are accompanied by itching, which gets worse at night. A common type of hand eczema, it worsens in warm weather. (ICD-10 L30.1) Discoid Discoid eczema (nummular eczema, exudative eczema, microbial eczema) is characterized by round spots of oozing or dry rash, with clear boundaries, often on lower legs. It is usually worse in winter. The cause is unknown, and the condition tends to come and go. (ICD-10 L30.0) Venous Venous eczema (gravitational eczema, stasis<unk> , varicose eczema) occurs in people with impaired circulation, varicose veins, and edema, and is particularly common in the ankle area of people over 50. There is redness, scaling, darkening of the skin, and itching. The disorder predisposes to leg ulcers. (ICD-10 I83.1) Herpetiformis<unk>  herpetiformis (Duhring's disease) causes an intensely itchy and typically symmetrical rash on arms, thighs, knees, and back. It is directly related to celiac disease, can often be put into remission with an appropriate diet, and tends to get worse at night. (ICD-10 L13.0) Neurodermatitis Neurodermatitis (lichen simplex chronicus, localized scratch<unk>  is an itchy area of thickened, pigmented eczema patch that results from habitual rubbing and scratching. Usually, there is only one spot. Often curable through behaviour modification and anti-inflammatory medication. Prurigo nodularis is a related disorder showing multiple lumps. (ICD-10 L28.0; L28.1) Autoeczematization Autoeczematization (id reaction, auto sensitization) is an eczematous reaction to an infection with parasites, fungi, bacteria, or viruses. It is completely curable with the clearance of the original infection that caused it. The appearance varies depending on the cause. It always occurs some distance away from the original infection. (ICD-10 L30.2) Viral There are eczemas overlaid by viral infections (eczema herpeticum or vaccinatum), and eczemas resulting from underlying disease (e.g., lymphoma). Eczemas originating from ingestion of medications, foods, and chemicals, have not yet been clearly systematized. Other rare eczematous disorders exist in addition to those listed here.
Dermatitis
Psoriasis
Photokeratitis
Scabies
Keratitis
Dermatitis herpetiformis
Arthralgia
Lichen simplex chronicus