Atopy T78.4

R. Coca and A. Cooke 1923

Familial, polygenic disposition to hypersensitivity of skin and mucous membranes. There is an increased tendency to type I sensitization to allergens. Atopy can manifest itself as rhinitis, conjunctivitis allergica, allergic bronchial asthma, atopic dermatitis or (preferably in children) food allergy. The prevalence of atopy is about 25-30% of the total population. The trend is considered to be increasing.

Atopy stigmata/indications are:

• White Dermographism
• Fur cap-like hair trimming
• Halonated eyes
• Hyperlinear palm relief, for delicate palms
• Grey-white skin colour
• Acrocyanosis
• Positive prick test for inhaled and nutritive allergens
• IgE elevated.

Atopic minimal forms

• Sebostasis with pityriasiform scaling
• Earlobe rags
• Hyperkeratotic fingertips with a tendency to form rhagades(dermatitis hiemalis)
• Hyperhidrosis of the hands and feet and dyshidrosis
• Double eyelid crease (Dennie Morgan crease)
• Eyelid eczema (usually accompanied by periorbital shading, see above)
• Thinned lateral eyebrows (Hertogesches sign)
• Cheilosis with scaly erosive changes of the lips up to the formation of oral rhagades(Perlèche)
• dirty neck
• atopic genital eczemas

The term "atopia" is derived from "atopos", the wrong place, and means the unusual.

It is discussed whether there is an association between atopy and urticaria. In one study it was reported that 23% of all patients with chronic recurrent urticaria were atopic (corresponds to the general population).

Atopy and anaphylaxis are not synonymous terms. Atopy denotes a characteristic, anaphylaxis a reaction.

An atopic person does not necessarily have to develop an allergy. An allergy sufferer does not necessarily have to have an atopic background to develop an allergic reaction!

1. Buss YA et al (2007) Chronic urticaria-which clinical parameters are pathogenetically relevant? A retrospective investigation of 339 patients. J Dtsch Dermatol Ges 5: 22-27
2. Jackola DR et al (2004) Allergen Skin Test Reaction Patterns in Children (≤ 10 Years Old) from Atopic Families Suggest Age-Dependent Changes in Allergen-IgE Binding in Early Life. Int Arch Allergy Immunol 132: 364-372
3. Montealegre F et al (2004) Comparative prevalence of sensitization to common animal, plant and mould allergens in subjects with asthma, or atopic dermatitis and/or allergic rhinitis living in a tropical environment. Clin Exp Allergy 34: 51-58
4. Peebles RS Jr (2004) Viral infections, atopy, and asthma: Is there a causal relationship? J Allergy Clin Immunol 113: S15-18
5. Rödinger C et al (2013) Atopic dermatitis - State of the Art. Compendium Dermatology 9: 6-8
6. Sackesen C et al (2004) Decreased prevalence of atopy in paediatric patients with familial Mediterranean fever. Ann Rheum Dis 63: 187-190
7. Wright AL (2004) The epidemiology of the atopic child: Who is at risk for what? J Allergy Clin Immunol 113: 2-7