Systemic Contact Dermatitis

Cardiac implantable electronic devices (CIEDs) and allergy

Advances in cardiac implantable electronic devices (CIEDs) have prolonged life expectancy in various medical settings. However, the issue of hypersensitivity to components of CIEDs is still a concern. Since 1970, allergic reactions to metallic and nonmetallic components of CIEDs have been reported. Hypersensitivity reactions to medical devices are rare and not fully understood. In some cases, diagnosis and treatment are difficult. Cardiologists should always keep in mind pacemaker allergy when a patient appears with wound complications and no signs of infection. Patch testing should be tailored toward the specific biomaterials used in a device, in addition to testing with standard screening allergens in select cases.

Contact Dermatitis: Classifications and Management

Contact dermatitis (CD) is a common inflammatory skin disease caused by exposure to contact allergens and irritants. It is also the most common reason of occupational dermatitis and contributes greatly to hand dermatitis and facial dermatitis. Besides the two major forms of contact dermatitis: allergic contact dermatitis and irritant contact dermatitis, other subtypes of CD have been recognized including immediate skin reactions, photoinduced contact dermatitis, systemic contact dermatitis, and non-eczematous contact dermatitis. CD is a great imitator which can mimic many kinds of skin diseases, such as atopic dermatitis, lichen planus, and angioedema. For the diagnosis of CD, a complete medical history, including occupational history, is very important. It can give a clue of CD and provide a list of suspected substances. Besides the well-known diagnostic test, patch testing, there are many other diagnostic tests can be used to help diagnosis of CD and identify the causative allergens, including photopatch test, skin tests for detecting of immediate contact reactions, serum allergen-specific IgE test, and qualitative and quantitative testing of allergen in the suspected materials patients exposed to and challenge test. Before the treatment, the suspected irritants or allergens should be avoided completely. This includes both the removal of the patient from the environment that contains those substances and the promotion of the metabolism and expulsion of the allergens that have been absorbed by the body. In addition, it is also important to restore the skin barrier and reduce skin inflammation through multiple treatments, such as emollients, topical corticosteroids, and antihistamines, as well as systemic corticosteroids and immunosuppressants. Early and appropriate treatments are important to prevent further deterioration and persistence of the skin condition.

Systemic contact dermatitis

Systemic contact dermatitis is an inflammatory skin disease that may occur in persons with contact allergy when they are exposed to the hapten orally, transcutaneously, per rectum, intravesically, intravenously, or by inhalation. The most common causes of systemic contact dermatitis are drugs used both topically and systemically. Other causes are ubiquitously occurring haptens, such as the metals nickel, cobalt, gold, and chromate, and aromatic substances such as spices. Avoidance of the offending hapten is the most obvious treatment. For some haptens, such as nickel, diet treatment may be effective. Chelation therapy with disulfiram is another therapeutic option in nickel-allergic patients with systemic contact dermatitis. Hyposensitization therapy has been attempted with some success in systemic contact dermatitis caused by nickel and Parthenium hysterophorus.

Hand eczema guidelines based on the Danish guidelines for the diagnosis and treatment of hand eczema

BACKGROUND

Classification of hand eczema has traditionally been based both on aetiology and clinical appearance. For 20% of cases, the aetiology is unknown.

OBJECTIVES

To suggest a classification based on well-defined aetiology as well as on predefined clinical patterns and on the dynamics of hand eczema.

METHODS

Literature studies and discussions among members of the Danish Contact Dermatitis Group.

RESULTS

Criteria are given for the aetiological diagnoses of allergic contact dermatitis of the hands, irritant contact dermatitis of the hands, protein contact dermatitis of the hands, atopic hand eczema and aetiologically unclassifiable hand eczema. Six different clinical patterns are described and illustrated. Suggestions for general treatment principles are given.

CONCLUSION

Operational guidelines for the diagnosis and treatment of hand eczema are described.