ALLERGY DIAGNOSTIC TESTS (Greek allos — another and ergon — action) — diagnostic methods of allergic diseases and diseases with an allergic component in a pathogeny. Tests are based on local or general reaction of a sensibilized organism in response to administration of specific allergen.
At diagnosis of allergic diseases in the course of collecting the anamnesis allocate alleged group of allergens which could cause hypersensitivity disease in the patient. With these allergens carry out Allergy Diagnostic Tests out of a phase of an exacerbation of a disease. Apply skin, provocative and eliminative Allergy Diagnostic Tests.
Skin tests (see) — the safest and simple look And. dative. Depending on a way of administration of allergen there are application, scarifying and intracutaneous tests.
Application tests apply at hypersensitivity to simple chemical substances, a nek-eye to medicines at patients with contact dermatitis.
To to scarifying tests resort at hypersensitivity to pollen, household and epidermal allergens at patients with pollinoses, bronchial asthma, allergic rhinitis, small tortoiseshell and a Quincke's edema.
Intracutaneous tests apply at hypersensitivity to bacterial and fungal allergens at patients with bronchial asthma, chronic recurrent small tortoiseshell and infectious diseases. These tests by 100 times are more sensitive, than scarifying, but are less specific and give more complications. It is necessary to remember that some allergens (penicillin and other antibiotics) at statement And. sick with hypersensitivity to these drugs heavy complications (shock) during the carrying out scarifying and especially intracutaneous tests can cause dative. Sometimes apply to diagnosis Prausnittsa — Kyustnera reaction (see).
Skin Allergy Diagnostic Tests use also at some infectious and the parasitic diseases which are followed by an allergic sensitization of an organism. At diagnosis of tuberculosis apply a scarifying Pirquet's test and an intracutaneous test to Mant (see. Tuberculinodiagnosis ). At diagnosis of a brucellosis apply an intracutaneous test of Byurne; as allergen serves the solution of brucellin containing an antigenic set of three various causative agents of a brucellosis. At diagnosis of an echinococcosis apply an intracutaneous test of Kasoni. As allergen serves the extract from contents of a bubble of an echinococcus. At positive reaction in the place of an injection of allergen inflammatory reaction with a hyperemia and puffiness develops. At diagnosis of a tularemia apply an intracutaneous test with tularin (a heat-killed suspension of bacteria), at diagnosis of dysentery — test with dizenteriny Tsuverkalova. Some tests apply to detection of predisposition to infectious diseases: Dick's reaction — at diagnosis of scarlet fever, a Schick's test — in diagnosis of diphtheria.
Provocative tests (see) apply when data of the allergological anamnesis do not correspond to results of skin tests. Provocative tests are most specific in diagnosis of allergic diseases. There are nasal, conjunctival, inhalation and other provocative tests.
Nasal provocative test apply at diagnosis of allergic rhinitis: a pipette dig in in both nostrils on 2 — 3 drops of control liquid; in the absence of reaction begin a research with the increasing concentration of allergen; at difficulty of nasal breath, sneezing, a rhinorrhea test is considered positive.
Conjunctival test apply at diagnosis of pollinoses with the phenomena of conjunctivitis: after trial test with control solution allergen is dug in a pipette in the lower conjunctival sac; reddening, dacryagogue and an itch a century — signs of positive reaction. The inhalation test is applied at diagnosis of bronchial asthma: solution of allergen is given to the patient by means of the aerosol sprayer: at positive test the vital capacity of lungs decreases, develops a bronchospasm which is stopped bronchial spasmolytics. At use of provocative tests consider also late reactions.
Provocative tests apply also at diagnosis of a physical allergy (see. Allergy ). Cold test — at diagnosis of a chronic recurrent small tortoiseshell: the piece of ice is fixed by means of bandage; at a positive take in 10 min. after removal of ice on skin the urtikarny blister is formed. Thermal test is used for diagnosis of a small tortoiseshell: the test tube with hot water (t ° 40 — 42 °) is placed for 10 min. on skin of a palmar surface of a forearm. Positive reaction is characterized by formation on site of contact of an urtikarny blister.
Eliminative tests (see) apply hl. obr. at food allergy. The exception of food of estimated allergen is the cornerstone.
Bibliography: Adrianova N. V. and Titov S. M. Allergological office, M., 1970; Modern practical allergology, under the editorship of A. D. Ado and A. A. Polner, M., 1963.
V. A. Tomilets.