Discussion
In the AIT-workshop involving 46 doctors dealing with patients seeking care for seasonal allergic rhinitis, we found that the measurement of serum specific IgE to the major allergenic molecules of pollens (CRD) and the use of an eDiary significantly improved the accuracy of AIT prescription, not only among AS, but also in the group of GP.
In fact, when AS combined the “traditional approach” (anamnesis and SPT and/or IgE to pollen extracts) with these diagnostic tools (CRD and eDiary), they frequently modified and harmonized their AIT decision. The same trend was observed in the group of GP, who improved their clinical decision up to reproducing the standards of AS.
We have previously reported6 in another cohort (n=1271), that the inclusion of CRD in the diagnostic algorithm led to a change in AIT prescription for 44% of the patients. This might be explained by the presence of highly cross-reactive molecules from unrelated allergenic sources (e.g. profilins, polcalcins and LTPs), which may contribute to a confounding SPT-reactivity to extracts. Once this interference is ruled out by CRD, the clinical decision taking is simplified, especially for patients with various positive SPT results. Still, the clinical significance of individual sensitization profiles remains to be proven before prescribing the correct treatment. In order to overcome the inaccuracy of a retrospective symptom monitoring, the present study successfully assessed the use of digital symptom and medication recording. The access to this real-time clinical information increased the diagnostic precision of the GP and AS significantly.
In general, it is estimated that only a restricted minority (2-6%) of eligible patients currently receives AIT25. One reason for this condition may be the fact that most patients with seasonal allergic rhinoconjunctivitis are polysensitized26. The choice of the correct allergen for immunotherapy appears then often difficult, which may be the cause for clinicians to refrain from this therapeutic option. Yet, the differentiation between a pure polysensitization in mono-allergic patients and real poly-allergic subjects is fundamental, as an AIT prescription for the former is clearly recommended2. We found that also allergy specialists were more inclined to prescribe AIT when CRD and eDiary information were added to clinical history and SPT data. Therefore, more patients could benefit of AIT, which is currently the only disease-modifying treatment for SAR.
Our study may have several implications for the clinical practice. Even though CRD and eDiary have been available for more than one decade, guidelines for AIT have not yet adopted these diagnostic approaches. Our findings suggest that a more precise description of the patient’s sensitization profile before an AIT prescription should be taken into account. There is a need of controlled studies comparing the efficacy of AIT in patients in whom the therapeutic decision was based on SPT results vs SPT and CRD vs SPT, CRD and eDiary. Cost-benefit studies should also evaluate whether the immediate additional costs, implied by molecular analysis, are justified in the long-term period. Further, it is important to underline that the aim of CDSS should never be to replace a healthcare professional, but to enhance clinical routine by facilitating basic decisions and proper patient allocation at a primary care level.
We have to acknowledge some limitations of our study. First, the sample size is small, though 10% of whole population (200 patients) as suggested for pilot studies27. Second, our conclusions apply to settings with high pollen exposure for prolonged, seasonal periods, such as those of Mediterranean countries and the study should be repeated in other geographic areas on larger scale. Third, the forms filled by doctors were anonymous, so no sub-group analyses could be performed.
In conclusion, our findings suggest that in countries with high and prolonged exposure to various allergenic pollen sources, a clinical decision support system involving CRD and eDiary can improve the diagnostic precision of doctors in the clinical routine significantly. On one side, it can be useful in improving the diagnostic accuracy of AS with a positive impact on the therapeutic management and proper AIT prescriptions. On the other side, it can reinforce the crucial link between GP and AS by a more conscious referral to specialists by GP, which calls for a proper GP’s training and investigations regarding GP’s perceptions and expectations during the referral process. This conclusion might be useful to update national and international guidelines on the prescription of AIT in SAR. The hypotheses, that the precise identification of the proper allergen for AIT also improves its clinical efficacy, as well as cost-effectiveness, deserves to be tested.