The new diagnosis of parasitoses and allergies, this new the diagnosis of parasitoses and allergies with the aid of the reactant

摘要

Test for parasitosis and allergies associated with increased IgE levels is carried out by (a) treating a blood sample to obtain a suspension contg. 300-1000 polynuclear basophil cells per cubic mm, (b) incubating the suspension with various dilutions of specific antigen at 37 deg. C for 15 min. in wells on a test plate, (c) rapidly drying the test plate, (d) simultaneously fixing and staining the plate by contacting for 5-15 min. with an aq. alcohol soln. contg. a metachromic dye which selectively stains the cytoplasmic granules of basophil cells, and (e) counting the stained cells and calculating the degranulation index (DI), i.e. the % decrease in basophil cell count in the presence of the antigen. A DI of more than 35% represents a positive result. Step (a) is effected by (i) centrifuging the blood sample to obtain a leucocyte layer, (ii) homogenising the leucocyte layer with a non-destructive buffer (I), (iii) centrifuging with a liq. (II) having a specific gravity of 1.079-1.085 and an osmolarity of 280-320 milliosmoles to form a basophil-rich upper layer, and (iv) washing the upper layer with (I).. The test is esp. useful for early diagnosis of helminthiasis.