Changes in the Sensitization Pattern to Alternaria alternata Allergens in Patients Treated with Alt a 1 Immunotherapy

Abstract

Alternaria alternata is the most important allergenic fungus, with up to 20% of allergic patients affected. The sensitization profile of patients sensitized to A. alternata and how it changes when treated with immunotherapy is not known. Our objective is to determine the allergen recognition pattern of allergic patients to A. alternata and to study its association to the parameters studied in a clinical trial recently published. Sera of 64 patients from the clinical trial of immunotherapy with native major allergen Alt a 1 were analyzed by immunoblotting; 98. 4% of the patients recognized Alt a 1. The percentage of recognition for Alt a 3, Alt a 4, and/or Alt a 6, Alt a 7, Alt a 8, Alt a 10 and/or Alt a 15 was 1.6%, 21.9%, 12.5%, 12.5%, and 12.5% respectively. Of the 64 patients, 45 (70.3%) only recognized Alt a 1 among the allergens present in the A. alternata extract. Immunotherapy with Alt a 1 desensitizes treated patients, reducing their symptoms and medication consumption through the elimination of Alt a 1 sensitization, which is no longer present in the immunoblotting of some patients. There may be gender differences in the pattern of sensitization to A. alternata allergens, among others.

Molecular allergy diagnosis is sensitive and avoids misdiagnosis in patients sensitized to seasonal allergens

“…In addition, multiple studies have demonstrated that the use of molecular allergology leads to different therapeutic decisions compared to extract‐based testing 11–13 . The reported sensitivities of molecular pollen marker allergens are promising; 14–39 however, their transferability to routine diagnostics was questionable, because percentages varied considerably and many of the studies were performed with tests which are not routinely available such as immunoblotting, ELISA or prick testing with molecular allergens.…”

“…The benefit of molecular allergology and its impact on specific allergy diagnosis and therapy selection have been reported in several studies. [10][11][12][13] Previous sensitization rates to molecular marker allergens reported were as high as 80.7%-98.4% for Alt a 1, [14][15][16][17] 90%-100% for Amb a 1, [18][19][20][21][22] >70%->95% for Art v 1, [22][23][24][25][26] 88.5%-97% for Bet v 1, [27][28][29][30] 97.7% for Fra e 1 31 and 87.6%-88% for Ole e 1, 32,33 74.8%-98% for Phl p 1, [34][35][36][37][38][39] and 27.2%-80% for Phl p 5. 8,[34][35][36][37]40 However, most of these studies were based on experimental methods not routinely used or available such as immunoblotting, ELISA, or prick testing with molecular allergens.…”

Fungal Allergen and Mold Allergy Diagnosis: Role and Relevance of Alternaria alternata Alt a 1 Protein Family

“…According to data reported in the literature only Alternaria , Aspergillus , Penicillium and Cladosporium seem to be the strongest candidates for the development of severe asthma and rhinitis [ 4 , 13 , 36 , 47 , 48 , 49 , 50 ]. There are only a few case reports about the association between occupational fungal exposure and asthma involving the species: Pleurotus cornucopiae , Lycopodium clavatum , Dictyostelium discoideum , Rhizopus nigricans and Neurospora [ 13 ], whereas sensitization to Alternaria, Cladosporium and Aspergillus has a strong link with asthma severity [ 51 , 52 , 53 , 54 ]. Patients monosensitized to fungal allergens are associated with a high risk of developing clinical symptoms [ 55 ], while those who present multiple sensitizations to fungi are associated with poor asthma control [ 56 ].…”

“…This is especially important in the management of the allergic patient, including the decision on immunotherapy. According to Rodriguez et al, specific IgE to Alt a 1 should be assessed before considering the prescription of AIT in a patient with a clinically relevant sensitization to Alternaria [ 53 ]. In these cases, the major allergen Alt a 1, should be recognized as a marker of primary sensitization to this fungus.…”

Special Issue: Alternaria alternata: Should We Still Consider This Fungus as a Minor Brother in the Etiology of Respiratory Allergy?

“…This Special Issue features two articles of interest to clinicians who manage allergic patients. Lopez Couso and colleagues [ 9 ] highlight the importance and efficacy of Alt a 1 in the diagnosis of respiratory allergy due to Alternaria , as the most relevant fungal allergenic source, and, Rodriguez and colleagues [ 10 ] demonstrate that immunotherapy with Alt a 1 desensitizes treated patients, reducing their symptoms and medication consumption through the elimination of Alt a 1 sensitization.…”