title: Anomalous cutaneous absorption of allergens as cause of skin prick testing adverse reactions in adult patients. Clinical and experimental evidence.
abstract: BACKGROUND
  Paediatric age, active eczema and high number of allergens tested in poly-sensitized patients have been pinpointed as possible risk factors of systemic reactions by skin prick testing. As far as atopic eczema concerns, the higher penetration of the allergens into the skin because of the scraping or micro-injuries is an intuitive rationalization. Purpose of the present study is to provide documentary evidence that adverse reactions elicited by anomalous absorption of allergens can occur also in adult patients with apparently normal skin.
  
  
  METHODS
  Report of some exemplifying clinical and experimental observations. Measuring the inoculum volume into impaired skin and its variability in relation to the variation of the chemical-physical characteristic of the solutions used for the tests by means of a method of direct assay based on the use of a gamma-camera.
  
  
  RESULTS
  Localized impairments of the skin permeability can cause a significant increase in inoculum volume by prick-test. Critical amounts of allergens can be introduced into the skin because of the possibility of direct absorption, also without pricking, of allergy diagnostic solutions. The greater water content of the solutions used for prick-testing can significantly increase the inoculum volume.
  
  
  CONCLUSIONS
  This study adds clinical and experimental evidences that localized impairments of permeability can occur in adult patients with apparently normal skin. Special precautions should be taken when a change of the drops' normal shape and cohesion is seen, because allergy prick-testing in such areas is potentially associated with increased risk of large local or systemic reactions.
authors.affiliation: Allergy Unit, Ospedale Civile, Volta Mantovana, MN, Italy. Servizio di Allergologia Ospedale Civile Srl Via Tonello 5 46049 Volta Mantovana, MN, Italy Fax: +39 0376 839 212 E-mail: antico47@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Antico
authors.affiliation: Physic Department, Cremona Hospital, Cremona, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Arisi
authors.affiliation: Nuclear Medicine Department, Cremona Hospital, Cremona, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Lima
mesh_terms: D000328:Adult; D000485:Allergens / Q000493:pharmacokinetics*; D005260:Female; D006801:Humans; D008297:Male; D012869:Skin Absorption; D012882:Skin Tests / Q000009:adverse effects*
chemical_list: D000485:Allergens
keywords: prick-test inoculum volume variability; skin absorption; skin permeability barrier; skin prick-test; skin tests adverse reactions