Sensitization to chloramphenicol

Systemic allergic dermatitis (systemic contact dermatitis) from pharmaceutical drugs: A review

The literature on systemic allergic dermatitis (SAD; also known as systemic contact dermatitis) is reviewed. Both topical drugs (from absorption through mucosae or skin) and systemic drugs (oral, parenteral, rectal) may be responsible for the disorder. The topical route appears to be rare with 41 culprit topical drugs found to cause SAD in 95 patients. Most reactions are caused by budesonide (especially from inhalation), bufexamac, and dibucaine. SAD from systemic drugs is infrequent with 95 culprit drugs found to cause SAD in 240 patients. The drugs most frequently implicated are mitomycin C, methylprednisolone (salt, ester), and hydrocortisone (salt). The largest group of culprit drugs consisted of corticosteroids (19%), being responsible for >30% of the reactions, of which nearly 40% were not caused by therapeutic drugs, but by drug provocation tests. The most frequent manifestations of SAD from drugs are eczematous eruptions (scattered, widespread, generalized, worsening, reactivation), maculopapular eruptions, symmetrical drug-related intertriginous and flexural exanthema (SDRIFE [baboon syndrome]) and widespread erythema or erythroderma. Therapeutic systemic drugs hardly ever cause reactivation of previously positive patch tests and infrequently of previous allergic contact dermatitis. The pathophysiology of SAD has received very little attention. Explanations for the rarity of SAD are suggested.

Allergic contact dermatitis to topical antibiotics: Epidemiology, responsible allergens, and management

Topical antibiotics are widely used to treat cutaneous, ocular, and otic infections. Allergic contact dermatitis to topical antibiotics is a rare but well-documented side effect, especially in at-risk populations. The purpose of this article is to review the epidemiology, responsible allergens, and management of allergic contact dermatitis to topical antibiotics.

LEARNING OBJECTIVE

After completing this learning activity, participants should be able to describe the epidemiology of allergic contact dermatitis related to topical antibiotics; show knowledge of the most common allergenic topical antibiotics; and understand the allergenic cross-reactivity pattern amongst topical antibiotics.

Intradermal testing in the diagnosis of allergic contact dermatitis. A reappraisal

Contact hypersensitivity may be diagnosed with patch testing or intradermal testing. Although these methods have been used earlier in parallel, patch testing has gradually become the only method in routine diagnosis of contact allergy. Recent findings in corticosteroid contact hypersensitivity have shown that patch testing is not always an optimal method, especially when poor penetrants are used. Therefore, a reappraisal of intradermal testing is presented, based on the literature. Studies employing both patch and intradermal testing are reviewed and the advantages and disadvantages of intradermal tests as compared to patch tests in contact allergy diagnostics are discussed. We find that it might be worthwhile to evaluate whether contact allergy to compounds other than corticosteroids may be easier to detect with intradermal than patch test.