Allergen immunotherapy is safe during pollen season. Results of a 10-year, real-life prospective study

• Published in: Revue française d'allergologie (2009) 2017-06, Vol.57 (4), p.302-307
• Main Authors: Pitsios, C., Lefoussis, C., Dimitriou, A., Giannakopoulos, D., Ergazakis, M., Vartholomaios, S., Kouri, M., Larenas-Linnemann, D., Kompoti, E.
• Format: Article
• Language: English
• Subjects: Allergen immunotherapy; Anaphylaxie; Anaphylaxis; Dose d’entretien; Effets secondaires; Immunothérapie allergénique; Maintenance dose; Pollen season; Saison pollinique; Side-effect
• ISSN: 1877-0320; 1877-0320
• DOI: 10.1016/j.reval.2017.01.008

Although systemic reactions (SRs) due to allergen immunotherapy (AIT) are rare, preventing them is a major concern for allergologists. Natural exposure during pollen season is a controversial risk factor, so some centers reduce AIT's maintenance dose in-season. The aim of this study was to examine whether administering the maintenance dose of subcutaneous AIT (SCIT) during pollen season, without adjustment, is safe. Initially, a retrospective pilot study was conducted, that included thirty-four monosensitized patients treated with perennial SCIT without in-season dose adjustment during maintenance. Pollen counts were monitored with a Burkard trap, to validate the pollen season. Two SRs were registered; one during and the other out of season, showing no seasonal effect on SCIT's safety. A ten-year-long, prospective study using the same SCIT protocol, followed the pilot one. Seventy-eight monosensitized patients, allergic to Grasses or Parietaria or Olive pollen, completed this study, while 28 monosensitized mite-allergic patients served as a control group. Only standardized depot solutions were used. A total of 2910 pollen-extracts maintenance-dose injections were administered. Four SRs (Grade 1 or 2, WAO Classification) were registered; 2/1210 during pollen season and 2/1700 off-season. One (Grade 4) reaction, out of 880 mite extract injections, was registered. The presence of SRs did not correlate with any AIT brand. In our study population pollen season does not seem to be a risk factor for SRs for monosensitized allergic patients. SRs due to pollen AIT presented with a similar frequency as with mite AIT. Bien que les réactions systémiques (RS) de l’immunothérapie allergénique (ITA) soient rares, leur prévention est une préoccupation majeure des allergologues. L’exposition naturelle aux allergènes pendant la saison pollinique constitue un facteur de risque controversé, mais quelques centres diminuent la dose d’entretien de l’ITA pendant cette saison. L’objectif de cette étude était de savoir si, au cours de l’ITA par voie-sous-cutanée (ITA-SC), l’administration d’une dose d’entretien sans ajustement pendant la saison pollinique était sans risque. Initialement, une étude pilote fut effectuée incluant 34 patients monosensibilisés traités par une ITA-SC perannuelle sans ajustement pendant la saison pollinique. Les pollens étaient comptés à l’aide d’un capteur de Burkard pour valider la saison pollinique. Deux SR furent enregistrées, l’une pendant la saison