Cocksfoot

  • Allergen search puff

    SEARCH FOR ALLERGENS

    Search ImmunoCAP allergens and allergen components. Note that all information is in English.

Code: g3
Latin name: Dactylis glomerata
Source material: Pollen
Family: Poaceae (Gramineae)
Sub family: Pooideae
Tribe: Poeae
Common names: Cocksfoot grass Cock's foot grass, Cock's-foot, Orchard Grass, Orchardgrass
Recognized varieties include:
  • D. g. var. ciliata Peterm
  • D. g. var. detonsa Fries
A grass species producing pollen, which often induces hayfever, asthma and conjunctivitis in sensitised individuals.

Allergen Exposure

Geographical distribution
Of Eurasian temperate zone origin, Cocksfoot was introduced to the eastern United States in 1760. It is now found throughout most of U.S., except for desert or arctic regions, and also grows in the temperate regions of Africa (Kenya, Tanzania, Rhodesia, S. Africa), Australia (NSW, Victoria, and other areas of southern Australia) and South America (Brazil, Colombia, Venezuela, Argentina). It is widespread in Europe and temperate Asian regions such as Japan, where it is a major pollen source. It is one of the commonest grasses, and is widely used for forage and hay. It is one of the best grasses for cultivating in shady areas.

Cocksfoot is an evergreen perennial bunchgrass growing to 1.4 m tall and with a deep root system. The plant is non-rhizomatous, reproducing by seeds and tillers. It has erect, glabrous culms, and blades 10 to 60 cm long and 0.2 to 1.1 cm wide. The inflorescence is a panicle 8 to 20 cm long with 2 to 6 florets per spikelet, and the spikelets tightly clustered on one side of the blade. This arrangement has been compared to the foot of a cockerel.
 
In North America it flowers from April/May to August, and in Europe from June to September. The flowers are hermaphrodite (have both male and female organs) and are pollinated by wind. The seeds ripen from July to September.
 
Environment
The plant grows on roadsides, lawns, fields, ditch banks, meadows, and waste places, often in the wake of disturbance. It prefers woodland and other dappled shade, and even occasionally occurs in desert shrub communities. It is frequently planted for ground cover, soil stabilization and biomass, but especially for pasture and hay.
 
The plant is a folk remedy for treating tumours and kidney and bladder ailments.
 
Allergens
To date many IgE-binding components have been isolated, major allergen groups identified, and allergens indicated by cross-reactive studies (1-8).  
  • Dac g 1 (9-11) 
  • Dac g 2 (12)
  • Dac g 3, a 14 kDa protein (13) 
  • Dac g 4, a major 59 kDa protein (14-15) 
  • Dac g 5 (16-17) 
Dac g 3 is recognised by more than 60% of sera from Dactylis glomerata pollen-allergic individuals (13).
 
In the Dactylis glomerata plant, allergenic components are most highly concentrated in the pollen, but are also present in the leaves and show traces in the stems (18).

Potential Cross-Reactivity

An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Poaceae; and is especially likely for members of the subfamily Pooideae (Rye grass (g5), Canary grass (g71), Meadow grass (g8), Timothy (g6), Cocksfoot (g3), Meadow Fescue (g4), Velvet grass (g13), Redtop (g9), Meadow Foxtail (g16), Wild Rye grass (g70)) (19-20).  
 
This grass contains Group 1 allergens, to which more than 95% of patients allergic to grass pollen possess IgE antibodies. These are highly cross-reactive glycoproteins exclusively expressed in the pollen of many grasses (21-23).
 
Group 1 allergens are highly homologous, but not all of the antigenic epitopes are crossreactive (24). For example, Group 1 allergens from eight different clinically important grass pollens of the Pooideae (Rye grass, Canary and Meadow grass, Cocksfoot and Timothy), Chloridoideae (Bermuda grass) and Panicoideae (Johnson grass, Maize) were isolated, and IgE binding to an allergic human serum pool was conducted to determine the degree of antigenic and IgE-binding similarities. The highest IgE-binding similarity was observed between Cocksfoot and Rye grass (53%) and between Rye grass and Canary grass (43%). No IgE-binding similarity was observed between Maize and other grasses. The highest antigenic similarity was also observed between Rye grass and Cocksfoot grass (76%), and the lowest similarity between Maize (23%) and Bermuda (10%) (25). 

The major Timothy grass pollen allergen Phl p 1 also cross-reacts with most grass-, Corn- and monocot-derived Group 1 allergens including Dac g1 (26). Monoclonal antibodies of Cyn d 1 (Bermuda grass) recognised cross-reactive epitopes on proteins from eight other grasses including Cocksfoot, Rye grass, Timothy grass, Meadow grass and Johnson grass (27).
 
T-cell lines specific for Phl p 1 (the Group I allergen of Timothy grass, Phleum pratense) from the sera of 9 patients allergic to grass pollen displayed IgE binding with grass pollen extracts from Dactylis glomerata (Cocksfoot), Poa pratensis (Meadow grass), Lolium perenne (Rye grass), and Secale cereale (Cultivated Rye), and selected amino acid sequence-derived peptides. Cross-reactivity studies revealed cross-reacting and non-cross-reacting T-cell epitopes (28).
 
Immunological identity between recombinant Dac g 2 (from Cocksfoot grass) and Lol p 1 and Lol p 2 (both from Rye grass) has been demonstrated. Similar cross-identity was observed with pollen extracts from three other grass species: Festuca rubra (Red Fescue), Phleum pratense (Timothy grass) and Anthoxanthum odoratum (Sweet Vernal grass). Recombinant Dac g 2 was recognised by species- and group-cross-reactive human IgE antibodies in 33% (4/12) of sera randomly selected from grass-sensitive individuals and in 67% (14/21) of sera from patients receiving grass pollen immunotherapy (12).
 
A sequence identity of 65% was found between Dac g 3 allergen and Lol p 3 (Rye grass), suggesting that these allergens are homologues. Computer analyses showed that, in spite of a high degree of sequence homology, even closely related allergens such as Dac g 3 and Lol p 3 have dissimilar predictive secondary structures and different potential antigenicity (13).
 
Cocksfoot grass also contains a Group 4 allergen. Group 4 grass pollen allergens are glycoproteins with a molecular weight of 50 to 60 kDa, which are present in many grass species. Almost 75% of patients allergic to grass pollen display IgE reactivity to Group 4 allergens, which hence can be regarded as major grass pollen allergens (29). Phl p 4 represents a trypsin-resistant major Timothy grass pollen allergen with immunologic similarities to the major ragweed allergen Amb a 1 and therefore must be considered an important cross-reactive component in grass pollen and weed pollen allergy (29). Inhibition studies of IgE antibody binding to Dac g 4 (Dactylis glomerata - Cocksfoot grass) and to other pollen extracts confirmed the presence of cross-reactive allergens in Secale cereale (Cultivated Rye), Lolium perenne (Rye grass), Festuca elatior (Meadow Fescue), Holcus lanatus (Velvet grass), Bromus arvensis (Field Brome), Poa pratense (Meadow grass), Hordeum sativum (Barley), and Phleum pratense (Timothy grass) (14).

Phl p 4 homologes with similar molecular weight were detected in Dactylis glomerata (Cocksfoot grass), Festuca pratensis (Meadow Fescue), Holcus lanatus (Velvet grass), Poa pratensis (Meadow grass), and Lolium perenne (Rye grass).

Group 4 homologes were present in the various grass extracts, but to different extents (15).
 
Cocksfoot grass pollen also contains a Group 5 allergen. Almost 90% of grass pollen-allergic patients are sensitised against Group 5 grass pollen allergens. Group 5 allergens have been detected in Timothy, Rye grass, Meadow grass and Cocksfoot extracts. The major components in these fractions were found to be 25-28 kDa proteins, and IgE binding to these components was confirmed using a pool of grass-allergic sera (30).
 
The variability of cross-reactivity of IgE antibodies to Group 1 and 5 allergens in Dactylis glomerata (Cocksfoot), Festuca rubra (Red Fescue), Phleum pratense (Timothy), Anthoxanthum odoratum (Sweet Vernal grass), Secale cereale (Cultivated Rye), Zea mays (Maize), and Phragmites communis (Common Reed) to IgE antibodies against Lol p I or Lol p V (from Rye grass) was investigated by means of RAST-inhibition. The degree of cross-reactivity was demonstrated to be highly variable. Individual sera were not always equally cross-reactive to all pollen species. A high degree of cross-reactivity for Group 1 allergens did not necessarily imply the same for Group 5. Group 1 and Group 5 representatives were found to be present in all 8 species (31).
 
An inhibition test has shown that the reactivity of the IgE antibody specific for Olive tree pollen antigen was inhibited dose-dependently by an extract of Cocksfoot grass pollen. These findings show that there is a reaction in some patients with grass pollinosis that might be induced by Olive tree pollen (32).
 
Sera from 3 patients with confirmed allergy to Melon, Cocksfoot and English Plantain pollens revealed that several distinct protein bands were shared by the three extracts at 14, 31, and a spectrum between 40 and 70 kDa, approximately. Extracts of Melon, Plantain and Cocksfoot showed that all allergens of Melon blotting were almost completely inhibited by grass and Plantago pollen extracts, supporting the theory that there are structurally similar allergens, and that all allergenic epitopes of Melon are present in these pollens (33-34).  
 
Sera from subjects diagnosed as allergic to White Cypress Pine, Italian Cypress, Rye grass or Birch pollen were shown to have IgE antibodies that reacted with pollens from these 4 species and from Cocksfoot, Couch grass, Lamb's Quarters, Wall Pellitory, Olive, Plantain and Ragweed. The authors conclude that the presence of pollen-reactive IgE antibodies may not necessarily be a true reflection of sensitising pollen species (35).
 
Four monoclonal antibodies raised to Cyn d 1 (Bermuda grass) were shown to cross-react with pollen components from other grass species, especially Meadow grass and Cocksfoot (27).
 
An early study suggested that Birch, Cocksfoot, Mugwort and Ragweed pollen might have shared allergens with an extract of Apple pulp (36).

Clinical Experience

IgE mediated reactions
Cocksfoot grass pollen is a very common allergen inducing asthma, allergic rhinitis and allergic conjunctivitis (37-39).  
 
In 187 patients in Madrid, Spain, with rhinitis and/or seasonal asthma, 92% were shown to have specific IgE to Cocksfoot pollen (40).
 
In a Polish study, 22 patients with seasonal allergic rhinitis between 13 and 53 years of age were examined for specific IgE to 5 grass and 3 weed pollens. The most common sensitisation was to Meadow Fescue (Festuca elatior), Meadow grass (Poa pratensis) and Cocksfoot (Dactylis glomerata) (41).
 
Cocksfoot grass has also been reported to be an important aeroallergen in Greece. In Athens, the most prevalent aeroallergen in patients with allergic rhinitis as shown by specific IgE determination was to Dactylis glomerata (Cocksfoot), Parietaria (Pellitory), Olea europea (Olive), Dermatophagoides (House Dust Mite) and several molds (42).
 
Similarly, in Turkey, as shown by specific IgE tests on 614 respiratory-allergic patients. Cocksfoot grass was among important grass pollens (43).
 
Cocksfoot grass is a very important aeroallergen in Japan, resulting in a high prevalence of sensitisation as determined by specific IgE determination (44-47). In 226 children attending an allergy clinic, overall average sensitisation rates were 38.5% for D. glomerata. Among children aged 12 or more, sensitisation rates for D. glomerata were much higher (56.3%) (48). Cocksfoot grass pollen was also shown to be a major cause of seasonal allergic rhinitis in a farming community in central Japan where Cocksfoot grass was planted for apple farming (49).
 
In Thailand, 18% of 100 patients with allergic rhinitis were shown by specific IgE determination to be sensitised to Cocksfoot grass (50).
 
One study indicated that Dactylis glomerata pollen is a trigger for or exacerbates atopic eczema (51).
 
Compiled by Dr Harris Steinman, harris@zingsolutions.com

References

  1. Brodard V, David B, Gorg A, Peltre G. Two-dimensional gel electrophoretic analysis with immobilized pH gradients of Dactylis glomerata pollen allergens. Int Arch Allergy Immunol  1993;102(1):72-80 
  2. Walsh DJ, Matthews JA, Denmeade R, Maxwell P, Davidson M, Walker MR. Monoclonal antibodies to proteins from cocksfoot grass (Dactylis glomerata) pollen: isolation and N-terminal sequence of a major allergen. Int Arch Allergy Appl Immunol 1990;91(4):419-25 
  3. Urisu A, Kodama H, Kanamori S, Kozawa T, Masuda S, Ichikawa Y, Imai K, Yazaki T, Torii S. Identification of orchard grass (Dactylis glomerata) pollen allergens by immunoblotting. [Japanese] Arerugi 1988;37(4):197-203 
  4. Mecheri S, Peltre G, Weyer A, David B. Production of a monoclonal antibody against a major allergen of Dactylis glomerata pollen (Dg1). Ann Inst Pasteur Immunol;136C(2):195-209 
  5. Mecheri S, Peltre G, David B. Purification and characterization of a major allergen from Dactylis glomerata pollen: the Ag Dg1. Int Arch Allergy Appl Immunol 1985;78(3):283-9 
  6. Ford SA, Tovey ER, Baldo BA. Identification of orchard grass (Dactylis glomerata) pollen allergens following electrophoretic transfer to nitrocellulose. Int Arch Allergy Appl Immunol 1985;78(1):15-21 
  7. Calam DH, Davidson J, Ford AW. Investigations of the allergens of cocksfoot grass (Dactylis glomerata) pollen. J Chromatogr 1983;266:293-300 
  8. Topping MD, Brostoff J, Brighton WD. Allergenic activity of fractions of cocksfoot (Dactylis glomerata) pollen. Definition of active components by skin testing, and inhibition RAST. Clin Allergy 1981;11(3):281-6
  9. van Ree R, Clemens JG, Aalbers M, Stapel SO, Aalberse RC. Characterization with monoclonal and polyclonal antibodies of a new major allergen from grass pollen in the group I molecular weight range. J Allergy Clin Immunol 1989;83(1):144-51 
  10. Mourad W, Mecheri S, Peltre G, David B, Hebert J. Study of the epitope structure of purified Dac G I and Lol p I, the major allergens of Dactylis glomerata and Lolium perenne pollens, using monoclonal antibodies. J Immunol 1988;141(10):3486-91 
  11. Mecheri S, Peltre G, Weyer A, David B. Production of a monoclonal antibody against a major allergen of Dactylis glomerata pollen (Dg1). Ann Inst Pasteur Immunol 1985;136C(2):195-209 
  12. Roberts AM, Van Ree R, Cardy SM, Bevan LJ, Walker MR. Recombinant pollen allergens from Dactylis glomerata: preliminary evidence that human IgE cross-reactivity between Dac g II and Lol p I/II is increased following grass pollen immunotherapy. Immunology 1992;76(3):389-96 
  13. Guerin-Marchand C, Senechal H, Bouin AP, Leduc-Brodard V, Taudou G, Weyer A, Peltre G, David B. Cloning, sequencing and immunological characterization of Dac g 3, a major allergen from Dactylis glomerata pollen. Mol Immunol 1996;33(9):797-806 
  14. Leduc-Brodard V, Inacio F, Jaquinod M, Forest E, David B, Peltre G. Characterization of Dac g 4, a major basic allergen from Dactylis glomerata pollen. J Allergy Clin Immunol 1996;98(6 Pt 1):1065-72 
  15. Fahlbusch B, Muller WD, Rudeschko O, Jager L, Cromwell O, Fiebig H. Detection and quantification of group 4 allergens in grass pollen extracts using monoclonal antibodies. Clin Exp Allergy 1998;28(7):799-807 
  16. Klysner S, Welinder KG, Lowenstein H, Matthiesen F. Group V allergens in grass pollens: IV. Similarities in amino acid compositions and NH2-terminal sequences of the group V allergens from Lolium perenne, Poa pratensis and Dactylis glomerata. Clin Exp Allergy 1992;22(4):491-7 
  17. van Oort E, de Heer PG, Lerouge P, Faye L, Aalberse RC, van Ree R. Immunochemical characterization of two Pichia pastoris-derived recombinant group 5 Dactylis glomerata isoallergens. Int Arch Allergy Immunol 2001;126(3):196-205 
  18. D'Amato G, De Palma R, Verga A, Martucci P, Liccardi G, Lobefalo G. Antigenic activity of nonpollen parts (leaves and stems) of allergenic plants (Parietaria judaica and Dactylis glomerata). Ann Allergy 1991;67(4):421-4 
  19. Yman L. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. 1982: ISBN 91-970475-09 
  20. Yman L. Pharmacia: Allergenic Plants. Systematics of common and rare allergens. Version 1.0. CD-ROM. Uppsala, Sweden: Pharmacia Diagnostics, 2000. 
  21. Grobe K, Becker WM, Schlaak M, Petersen A. Grass group I allergens (beta-expansins) are novel, papain-related proteinases. Eur J Biochem 1999;263(1):33-40 
  22. Schenk S, Breiteneder H, Susani M, Najafian N, Laffer S, Duchene M, Valenta R, Fischer G, Scheiner O, Kraft D, Ebner C. T cell epitopes of Phl p 1, major pollen allergen of timothy grass (Phleum pratense). Crossreactivity with group I allergens of different grasses. Adv Exp Med Biol 1996;409:141-6 
  23. Hiller KM, Esch RE, Klapper DG. Mapping of an allergenically important determinant of grass group I allergens. J Allergy Clin Immunol 1997 Sep;100(3):335-40 
  24. Esch RE, Klapper DG. Cross-reactive and unique Group I antigenic determinants defined by monoclonal antibodies. J Allergy Clin Immunol 1987;78:489-95 
  25. Suphioglu C, Singh MB, Knox RB. Peptide mapping analysis of group I allergens of grass pollens. Int Arch Allergy Immunol 1993;102(2):144-51 
  26. Focke M, Mahler V, Ball T, Sperr WR, Majlesi Y, Valent P, Kraft D, Valenta R. Nonanaphylactic synthetic peptides derived from B cell epitopes of the major grass pollen allergen, Phl p 1, for allergy vaccination. FASEB J 2001;15(11):2042-4 
  27. Smith PM, Avjioglu A, Ward LR, Simpson RJ, Knox RB, Singh MB. Isolation and characterization of group-I isoallergens from Bermuda grass pollen. Int Arch Allergy Immunol  1994;104(1):57-64 
  28. Schenk S, Breiteneder H, Susani M, Najafian N, Laffer S, Duchene M, Valenta R, Fischer G, Scheiner O, Kraft D, et al. T-cell epitopes of Phl p 1, major pollen allergen of timothy grass (Phleum pratense): evidence for crossreacting and non-crossreacting T-cell epitopes within grass group I allergens. J Allergy Clin Immunol 1995;96(6 Pt 1):986-96 
  29. Fischer S, Grote M, Fahlbusch B, Muller WD, Kraft D, Valenta R. Characterization of Phl p 4, a major timothy grass (Phleum pratense) pollen allergen. J Allergy Clin Immunol 1996;98(1):189-98 
  30. Klysner S, Welinder KG, Lowenstein H, Matthiesen F. Group V allergens in grass pollens: IV. Similarities in amino acid compositions and NH2-terminal sequences of the group V allergens from Lolium perenne, Poa pratensis and Dactylis glomerata. Clin Exp Allergy 1992;22(4):491-7 
  31. Van Ree R, Driessen MN, Van Leeuwen WA, Stapel SO, Aalberse RC. Variability of crossreactivity of IgE antibodies to group I and V allergens in eight grass pollen species. Clin Exp Allergy 1992;22(6):611-7 
  32. Miyahara S, Nakada M, Nishizaki K, Kawarai Y, Nishioka K, Hino H. Cross-reactivity to olive tree pollen and orchard grass pollen in patients with pollinosis. Acta Med Okayama 1997;51(3):167-71 
  33. Garcia Ortiz JC, Ventas P, Cosmes P, Lopez-Asunsolo A. An immunoblotting analysis of cross-reactivity between melon, and plantago and grass pollens. J Investig Allergol Clin Immunol 1996;6(6):378-82 
  34. Garcia Ortiz JC, Cosmes Martin P, Lopez-Asunolo A. Melon sensitivity shares allergens with Plantago and grass pollens. Allergy 1995;50(3):269-73 
  35. Pham NH, Baldo BA. Allergenic relationship between taxonomically diverse pollens. Clin Exp Allergy 1995;25(7):599-606 
  36. Sakamoto T, Hayashi Y, Yamada M, Torii S, Urisu A. A clinical study of two cases with immediate hypersensitivity to apple-pulp and an investigation of cross-allergenicity between apple-pulp allergen and some other pollen allergens. [Japanese] Arerugi 1989;38(7):573-9 
  37. Kitao Y, Sadanaga Y, Uno M, On N, Masuyama K, Ishikawa T. Investigation of the genetics in allergic rhinitis. The 4th report--HLA class I and II specificities of orchard grass pollinosis. [Japanese] Nippon Jibiinkoka Gakkai Kaiho 1988;91(4):516-20 
  38. Shimada T. Four years study on Japanese cedar, orchard grass and ragweed pollinosis in Yotsukaido City--radioallergosorbent test (RAST) results of 361 patients. [Japanese] Nippon Jibiinkoka Gakkai Kaiho 1986;89(7):864-71 
  39. Yamamoto Y, Tada R, Sakashita M, Sasabe T, Nakagawa Y, Yamada M, Wakano I, Yuasa Allergic reactivity in cases of Japanese cedar and orchard grass pollenosis of the conjunctiva. [Japanese] Nippon Ganka Gakkai Zasshi 1984;88(3):473-7 
  40. Subiza J, Cabrera M, Valdivieso R, Subiza JL, Jerez M, Jimenez JA, Narganes MJ, Subiza E. Seasonal asthma caused by airborne Platanus pollen. Clin Exp Allergy 1994;24(12):1123-9 
  41. Silny W, Kuchta D, Siatecka D, Silny P. Antigen specific immunoglobulin E to grass and weed pollens in the plasma of patients with seasonal allergic rhinitis. [Polish] Otolaryngol Pol 1999;53(1):55-8 
  42. Kontothanasi G, Moschovakis E, Tararas V, Delis A, Anagnostou E. Determination of sensitivity of inhalant allergens in patients with allergic rhinitis in West Athens. Rhinology 1995;33(4):234-5 
  43. Guneser S, Atici A, Cengizler I, Alparslan N. Inhalant allergens: as a cause of respiratory allergy in east Mediterranean area, Turkey. Allergol Immunopathol (Madr) 1996;24(3):116-9 
  44. Shida T, Akiyama K, Hasegawa M, Maeda Y, Taniguchi M, Mori A, Tomita S, Yamamoto N, Ishii T, Saito A, Yasueda H. Change in skin reactivity to common allergens in allergic patients over a 30-year period. Association with aeroallergen load. [Japanese] Arerugi 2000;49(11):1074-86 
  45. Masuda S, Takeuchi K, Yuta A, Okawa C, Ukai K, Sakakura Y. Japanese cedar pollinosis in children in our allergy clinic. [Japanese] Arerugi 1998;47(11):1182-9 
  46. Ishizaki T, Fueki R, Saito A, Egawa K, Doi I. A study of skin test with regard to age differences and agreement with positive results from the RAST and ELISA methods. [Japanese] Arerugi 1992;41(6):668-75 
  47. Masuda S, Urisu A, Kondo Y, Ichikawa Y, Horiba F, Tsuruta M, Yasaki T, Ishihara M, Iwata S, Suetsugu S. Allergic individuals to Japanese cedar or orchard grass consist of two subgroups based on the sensitization to Dermatophagoides pteronyssinus. [Japanese] Arerugi 1990;39(6):520-5 
  48. Kusunoki T, Korematsu S, Harazaki M, Ito M, Hosoi S. Recent pollen sensitization and its possible involvement in allergic diseases among children in a pediatric allergy clinic. [Japanese] Arerugi 1999;48(10):1166-71 
  49. Yokouchi Y, Shibasaki M, Noguchi E, Nakayama J, Ohtsuki T, Kamioka M, Yamakawa-Kobayashi K, Ito S, Takeda K, Ichikawa K, Nukaga Y, Matsui A, Hamaguchi H, Arinami T. A genome-wide linkage analysis of orchard grass-sensitive childhood seasonal allergic rhinitis in Japanese families. Genes Immun 2002;3(1):9-13 
  50. Pumhirun P, Towiwat P, Mahakit P. Aeroallergen sensitivity of Thai patients with allergic rhinitis. Asian Pac J Allergy Immunol 1997;15(4):183-5
  51. Darsow U, Behrendt H, Ring J. Gramineae pollen as trigger factors of atopic eczema: evaluation of diagnostic measures using the atopy patch test. Br J Dermatol 1997;137(2):201-

 

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.