Contact dermatitis to Asparagus officinalis

A 53-year-old farm worker presented with a 3-year history of an occupational allergic contact dermatitis to asparagus. The dermatitis cleared quickly with courses of systemic corticosteroids but relapsed within days of further exposure to asparagus. The genera Asparagus is made up of some 300 species. It belongs to the family Liliaceae which includes tulips, onions and garlic. Asparagus contains asparagin, coniferin and the glucoside vanillin. The allergen may be a plant growth inhibitor, 1,2,3-Trithiane-5-carboxylic acid, which is present in young shoots.     

Contact dermatitis from a presumed allergy to paraphenylenediamine

Paraphenylenediamine (PPD) is a potent skin allergen found in permanent hair dye and temporary henna tattoo ink. Several cases of adverse skin reactions to PPD have been reported in the literature. Here we present a case involving a patient who acquired a temporary tattoo while vacationing in Mexico and subsequently developed contact dermatitis at the tattoo site. He provided a history of permanent hair dye use in the past with associated cutaneous reaction. Temporary tattoos have become increasingly popular with travelers and as a result so have reports of associated allergic contact dermatitis. Of concern is cross‐reaction of PPD to related compounds, severe reactions in younger populations and sequelae including increased sensitization, permanent scarring, and persistent postinflammatory hyperpigmentation.     

Contact dermatitis to training toilet seat (potty seat dermatitis)

Allergic contact dermatitis from various components of toilet seats has been well described. We report a case of a young boy presenting with an atypical pattern of dermatitis who was found to be allergic to his training toilet seat. This case highlights the importance of recognizing this diagnosis and the role of potty seats as the causative factor.     

Contact dermatitis to aloe arborescens

A 66-Year-old Japanese male with allergic contact dermatitis to Aloe arborescens Mill var. natalensis had generalized nummular and papular dermatitis after 20 days use of topical aloe jelly. Patch testing with aloe jelly a strong reaction in the patient, but was negative in 8 controls.     

Contact dermatitis to chlorhexidine

In a 3-year period, 551 patients were patch tested with chlorhexidine gluconate 1% in water. 14 patients showed a strong and obviously relevant reaction. A severe dermatitis developed daring treatment with a chlorhexidine preparation in 10 patients with venous or traumatic ulcers of the leg, and in 4 patients with skin infection on the face and/or scalp. So far the sensitizing potential of chlorhexidine has probably been underestimated.     

The immunology of Contact dermatitis

This review summarizes current knowledge of the pathophysiological events which lie behind the development of contact dermatitis. The clinical distinction between allergic and irritant eczema is discussed. New observations are evaluated on our understanding of how allergic and irritant eczema may in many respects be similar, evolving through common physiological pathways of immune inflammation.