patch test

(redirected from Patch tests)
Also found in: Dictionary, Thesaurus, Legal, Financial, Encyclopedia.
Related to Patch tests: TRUE test

patch

 [pach]
a small area differing from the rest of a surface.
Peyer's p's whitish, oval, elevated patches of closely packed lymph follicles in mucous and submucous layers of the small intestine.
salmon patch a salmon-colored nevus flammeus usually found over the eyelids, between the eyes, or on the forehead. It is the most common vascular lesion of infancy, found in 40 per cent of newborns, and usually fades in the first year of life. Called also nevus simplex.
patch test a type of skin test for hypersensitivity in which filter paper or gauze saturated with the substance in question is applied to the skin, usually on the forearm; a positive reaction is reddening or swelling at the site.
Patch test.

patch test

a test of skin sensitiveness: a small piece of paper, tape, or a cup, wet with nonirritating diluted test fluid, is applied to skin of the upper back or upper outer arm and after 48 hours the covered is compared with the uncovered surface; an erythematous reaction with vesicles occurs if the substance causes contact allergy.
See also: photo-patch test.

patch test

n.
A test for allergic sensitivity in which a suspected allergen is applied to the skin on a small surgical pad.

patch test

Allergy skin test, contact dermatitis skin test, patch skin test Immunology An epicutaneous test of contact-type–delayed hypersensitivity, which consists of applying a patch with a low dose of an allergen–antigen to an unexposed area of the skin, usually the back, and observing the site 1-2 days later; the most common sensitizing haptens in North America are poison ivy–Toxicodendron radicans, nickel, chromate, paraphenylenediamine–a dye constituent, ethylenediamine–a solvent and emulsifier, local anesthetics–eg, benzocaine, rubber, neomycin, and others; PT materials have been standardized and are available commercially, either as individual allergens, or as batteries of allergens, including those for specific occupations–eg, hairdressers, printers, and others; incorrect PT results are common in the form of false-positives, due to too high concentration of allergens in the patches, misinterpretation of irritant reactions, and generalized erythema of the skin testing site; false-negative results are linked to technical errors and failure to simulate the 'real-world' situation in which the person is exposed to the allergen

patch test

(pach test)
A test of skin sensitiveness: a small piece of paper, tape, or a cup, wet with a dilute solution or suspension of test material, is applied to skin of the upper back or upper outer arm, and after 48 hours the area previously covered is compared with the uncovered surface; an erythematous reaction with vesicles occurs if the substance causes contact allergy.
See also: photo-patch test

patch test

Enlarge picture
APPLYING PATCH TEST
Enlarge picture
APPLYING PATCH TEST
Enlarge picture
APPLYING PATCH TEST
A skin test in which a low concentration of a presumed allergen is applied to the skin beneath an occlusive dressing. The test is the primary method used to determine the presence of allergic contact dermatitis. If the concentration of the agent is too high or an allergy exists to the material used in the dressing, false-positive reactions can occur as a result of local irritation. False-negative reactions may result if the concentration of the suspected allergen is too low, or if the duration of the test is too short. Commercially available, standardized kits to facilitate patch testing include the T.R.U.E. test and Finn Chambers. See: illustration; skin test
illustration

Patch test

A skin test that is done to identify allergens. A suspected substance is applied to the skin. After 24-48 hours, if the area is red and swollen, the test is positive for that substance. If no reaction occurs, another substance is applied. This is continued until the patient experiences an allergic reaction where the irritant was applied to the skin.
Mentioned in: Dermatitis, Skin Lesions

patch test

(pach test)
A test of skin sensitivity; a small piece of paper, tape, or a cup, wet with a dilute solution or suspension of test material, is applied to skin of the upper back or upper outer arm, and after 48 hours the area previously covered is compared with the uncovered surface; an erythematous reaction with vesicles occurs if the substance causes contact allergy.
References in periodicals archive ?
Changing trends in patch test reactions to accelerators.
Table 2 Frequency of positive patch test with 5% nickel sulphate (n=50).
In this study, the patch test with TCD was positive at 1% in an aqueous solution.
The diagnosis of OACD was established in cases meeting the following criteria [14-16]: (A) confirmed as a case of occupation-related CD; (B) exposure to the relevant occupational allergens; (C) confirmed positive patch test reaction to the relevant occupational allergens; and (D) exposure confirmed as a cause or as an important aggravating factor in the development of the skin diseases.
The Patch test reactions were graded according to the recommendations of the International Contact Dermatitis Research Group (ICDRG).
It was found in this research that reasonably accurate MPD can be obtained by laser scanning within 60 seconds, which is typically less than the time required for conducting a sand patch test. The laser texture scanner MPD was found to have a higher correlation to the MTD from sand patch tests.
Key words: Patch test, Allergens, Allergic contact dermatitis, Hispanic population
The exact solutions of the displacement fields for linear, quadratic and cubic patch tests are given in Equations 6, 7, and 8 as follows:
The adhesives have passed cytotoxicity studies, primary skin irritation studies and repeat insult patch tests. Telephone: 800-328-2619; Fax: 330-688-1153; E-mail: Mactactechnical@bemis.com; Web: www.mactac.com.
Skin patch tests use the patient's glove or latex product to screen for an immediate or delayed hypersensitivity and to evaluate the cause of the skin irritation Use of the latex product in question helps to ensure an accurate diagnosis since no standardized patch test exists.
When contact leukoderma from a potent depigmenting chemical is suspected, patch tests done to determine the allergen should be done, Dr.