Allergology assessment prior to administration of COVID-19 vaccine in patients with allergy history

Background: The diagnosis of drug allergy requires a previous medical history suggestive of a Drug Hypersensitivity Reaction (DHR). DHRs caused by vaccines are rare (< 1/100.000 doses) and are mainly due to excipients. At the beginning of the COVID-19 vaccination, occasional cases of severe reactions were reported in patients with allergy history. This warning led to an increased demand for allergy testing to evaluate pre-vaccination risk assessment, especially due to the refusal of allergic patients to receive the vaccine. Method(s): Twenty patients were evaluated between May to July 2021, referred for allergology study prior to receiving the vaccine against COVID-19. All patients tested had allergy history. Skin tests were performed with the available excipients of the COVID-19 vaccine: polyethylene glycol (PEG-1500, 10% prick ROXALL), polysorbate 80 (tween 80 prick 0.04 -ID 0.004 mg/ml), and trometamol (prick 1 -ID 0.1 mg/ml). A telephone follow-up was subsequently performed to assess tolerance to the vaccine. Result(s): The median age of the patients was 54.5 years and ninety percent were female. (Table 1) The most frequent allergy history was adverse drug reactions (ADRs) in 18 patients (90%), followed by bronchial asthma (35%), rhinitis (25%), food allergy (25%), and dermatitis (15%). 12 patients (60%) had multiple allergic diseases. The drugs implicated in these ADRs were beta-lactam antibiotics (40%), NSAIDs (20%), radiographic contrast media (15%), and vaccines (15%). Skin tests with the excipients studied were negative in all cases. Subsequently, the COVID-19 vaccine was administered in 16 patients (80%). Six patients (30%) reported side effects expected from the vaccine and no DHRs were described. Although vaccination was recommended to all patients after the study, 4 patients (20%) refused the administration. Conclusion(s): Patients with atopic history do not require an allergology study prior to the administration of the COVID-19 vaccine. Exceptionally, it may be necessary if the patient has a history of suspected DHRs to the excipients involved. The previous allergology assessment did not prevent refusal of vaccination in 20% of the patients. (Table Presented).

Practices of French and Francophones allergists in the management of allergic risks and complications of anti-SARS- COV- 2 vaccination

Background: The SARS-COV- 2 vaccination campaign has massively mobilized the allergists' community to screen patients deemed at risk for the SARS-COV- 2 vaccines. To describe data regarding the management of medical calls regarding the allergic risk for the SARS-COV- 2 vaccination, amongst French allergists. Method(s): A questionnaire-based survey was launched on the AdviceMedica platform (a platform of medical advice exchange between peers) between July and October 2021 (including two reminders). Result(s): Fifty-four allergists answered the survey. Three quarters of the responders were full-time allergists. Overall, 42% and 35% had an exclusive hospital or private practice, respectively. Allergists were mostly contacted by telephone (96.3%) and e-mail (79.6%), by general practitioners (92.6%) or physicians practicing in vaccination centers (88.8%) (median of vaccine related medical calls: 10 per week (Q25-Q75: 7-20, range (2-300). Allergists favored in-person visits rather than teleconsultations (85.2% vs. 61.1%). Allergy testing was prescribed for suspicions of allergy to polyethylene glycol (84.4%) or other vaccines and non-identified drugs (64.4%). Half of the responders (29, 53.7%) could perform vaccination and four (13.7%) declared reactions during vaccination. The responders used several tools in taking their clinical decision: exchanges with peers from the AdviceMedica platform (40.4%), advice from tertiary university hospital allergy units (25%), recommendations of the French Society of Allergy (17.3%). The three most frequent drawbacks that the allergists encountered were: having a hard time adding supplementary patient visits within optimal delays (three quarters of the responders), the reluctance expressed by the physicians requiring the advice and by the patients (two thirds) and the fact that the learnt society recommendations were deemed not to cover many on-field situations (one third). The major benefits from screening were estimated to be the lack of allergy contraindication to vaccination (88.7%) and the increased visibility of the allergist's role (69.8%). Conclusion(s): This survey put numbers on the management of screening patients deemed at risk for the SARS-COV- 2 vaccination amongst French allergists. Peer exchange was the most frequent tool in taking a clinical decision.

Allergist coorporation, the COVID-19 vaccination's keystone

Background: The French vaccination campaign against COVID-19 was accompanied by an overwhelming increase in allergists work load highlighting our key role in the stratification of the allergy risk prior to vaccination. Method(s): In order to describe our triage and testing experience for the COVID-19 vaccination all requests were analysed in a standardized way prospectively. Our final goal was to filter the requests and avoid any delay in the vaccination process. We first set up and validated locally a questionnaire (completed by the requesting practitioner) allowing to evaluate the risk of allergy to the vaccine, based on the clinical history of the patient. Questionnaire-based allergy advices were delivered (regular vaccination or allergy testing prior to vaccination). Result(s): From January 2021 to January 2022, we addressed 1047 requests. Forty-one patients (4%) were tested. 96% had allergies to other compounds, not increasing the risk of reacting to the covid vaccines and were vaccinated safely. Half of the tested patients experienced an immediate reaction to the vaccine and the other half had a history of allergy to the vaccine's components. We identified 3 groups of patients: -Suspicions of polyethylene glycol (PEG) containing laxative allergy comprised 8 patients (26%), including 2 cases with proven IgE-mediated allergy to PEG. They were 63% (5) women, 63% (5) atopic (average age of 49 +/-10 yrs). Two thirds (63%, 5 patients) had an immediate reaction to PEG, including 3 and 2 patients with anaphylaxis with and without shock, respectively. The two allergic patients refused vaccination and received a certificate of contraindication to PEG-containing vaccines (as per French law). -Reactions to the covid vaccine comprised 21 patients: most were women (86%, 18 patients) and 29% (6) were atopic (average age was 51 +/-19 yrs). Three quarters (76%, 16 patients) presented a reaction within 1 hour after the vaccination, considered as potential anaphylaxis in 12 patients (8 patients with and 5 without shock). 100% (21 patients) were tested negative. Twenty patients (95%) were further vaccinated without reaction. One required H1 antihistamine. -Suspicions of allergy to PEG or polysorbate as excipients included 12 patients (29%). Most clinical histories were anaphylactic (42% without and 33% with shock). Following negative excipient skin testing, regular vaccination was authorized. Conclusion(s): Overall, only 4% of the initial requests were deemed eligible for allergy testing. We did not diagnose any allergy in patients who reacted to the vaccines and we delivered two certificates of contraindication to mRNA COVID-19 PEG-containing vaccines in two cases of confirmed IgE-mediated allergy to PEG.

Vaccination against COVID-19 virus for the allergic population in Israel -The experience in a tertiary hospital, Sheba Medical Center in Israel

Background: In December 2020, the vaccination campaign against COVID-19 virus started around the world. The Israel Ministry of Health decided to use vaccines for COVID-19 from Pfizer/Biontech. Early studies with Pfizer COVID-19 vaccines reported that there was a risk of allergic reactions in Britan and several in USA. The patients who had allergic reactions to the vaccine reported prior history of various allergies. Due to these reports Israel Ministry of Health issued warnings cautioning patients with allergies regarding receiving the vaccine. The leading hypothesis was that one of the components of the vaccine, PEG or polyethylene glycol, was the cause of allergic reactions. This substance if found in many other medications.Following these developments, there was a flood of inquiries from the allergic patients in Israel Method: We established a call center in Sheba Medical Center that provided preliminary screening for inquiries from the public. The patients were divided into 3 groups: 1. Patients at low/medium risk level -These patients were vaccinated in the local clinics. Example of patients in this category included patients with allergic rhinitis, well controlled asthma, food allergies, insect venom allergy and mild drug allergy;2. Patients at high risk -These were the patients with more serious drug allergies, not related to PEG. These patients received COVID-19 vaccination under supervision at the Sheba Medical Center;3. Patients at very high risk -These patients had anaphylaxis or severe allergic reactions to IV medications, prior vaccines or PEG. They had a full evaluation at our allergy department including a thorough history and physical and specific allergy testing for PEG and Pfizer COVID-19 vaccine. Result(s): There were 810 patients over the age of 16, who were in high-risk group, and received vaccination in the hospital under supervision of a medical team including allergy physicians and nurses. 217 of these patients were categorized as very high risk and had a full allergy evaluation prior to the vaccination. Out of the patients in the very high risk group, only 5/217 (2.3%) were found to be allergic due to positive skin tests to the vaccine or one of its components. Of all the high risk patients 794/810 (98%) were vaccinated with no immediate response to the vaccine. The 16 patients (2%) had immediate allergic reactions and out of this group 6 (0.7% of total) had an anaphylactic reaction. Conclusion(s): This project describes how an effective algorithm can be established to deal with an urgent need to vaccinate majority of the population.Our data show that the risk of allergic reactions to the Pfizer COVID-19 vaccine is small even within allergic population and that most of the patients can receive the vaccine safely.

Anaphylactic reactions after COVID-19 vaccination in Germany.

. For the COVID-19 vaccines used in Germany, severe allergic (anaphylactic) reactions after vaccination have been reported in very rare cases. While Comirnaty and Spikevax are mRNA vaccines, Vaxzevria and Jcovden comprise vector vaccines, and Nuvaxovid a recombinant spike protein vaccine. The reporting rate of anaphylaxis after mRNA vaccination was higher in females receiving their first vaccination dose, with 0.97 and 1.12 reports per 100,000 vaccinations for Comirnaty and Spikevax, respectively, compared with vaccinated males and subsequent vaccinations. The Paul-Ehrlich-Institut (PEI) investigated 106 responses of 321 cases of confirmed anaphylactic reactions concerning subsequent allergy testing and revaccination with a COVID-19 vaccine. The collected data indicate that only a small proportion of cases (22%) were IgE-mediated reactions. A large proportion (73%) of patients could be revaccinated under precautionary measures without recurrence of anaphylaxis. The pathomechanism of the majority of anaphylactic reactions remains unclear and should be investigated in further studies.

Urticaria after SARS-CoV-2 vaccination.

Background: Infections are considered the most common known trigger of acute urticaria. Vaccinations can mimic infections and are also able to trigger urticaria. Method(s): This paper describes four exemplary patients with urticaria after SARSCoV-2 vaccination and discusses the occurrence of this adverse event with recent findings from the literature. Result(s): After SARS-CoV-2 vaccination, both acute (case 1) and chronic spontaneous urticaria (CSU) may occur for the first time (case 2) but a stable well-adjusted CSU may also worsen (case 3) or a pre-existing CSU may recur (case 4). The underlying pathomechanisms are not fully elucidated but activation of the immune system by vaccination seems plausible, similar to infection-triggered urticaria. Subsequent vaccinations are recommended even in the presence of a positive history of urticaria after SARS-CoV-2 vaccination and is often well tolerated;prophylactic administration of antihistamines should be considered. Allergy to vaccine components such as polyethylene glycol (PEG), which can lead to anaphylaxis, is comparatively rare. In cases of urticaria after SARS-CoV-2 vaccination, an accurate history allows risk assessment and provides the indication for further allergy diagnostic workup. Conclusion(s): Various forms of urticaria are a relatively common cutaneous side effect of SARS-CoV-2 vaccination in cases of pre-existing predisposition. They are not a contraindication to further vaccination. There is no need for further allergy diagnosis in the majority of cases.Copyright ©2023 Dustri-Verlag Dr. K. Feistle.

Allergological clarification of suspected COVID-19 vaccine allergy in the Christmas week 2021: organization and findings of a pilot study

Background: In 2020 the COVID-19 pandemic spread due to the coronavirus SARS-CoV-2. Vaccination is crucial to fight the COVID-19 pandemic. Initial reports of anaphylaxis after vaccination caused concern and fear of the population and consequently a high demand for allergy testing. Method(s): The need and reasons for allergy testing were recorded via questionnaires and the patients' medical history. To study the possibility of higher-throughput allergy evaluation, additional new skin test appointment slots were created for patients concentrated during the Christmas week 2021 and the amount of material, time required, as well as the organization and the tolerability of subsequent vaccination were analyzed. Result(s): The demand for testing greatly exceeded the number of available standard appointment slots. Test indications were mostly the patients' fear of an allergic reaction to the vaccine when a polyethylene glycol (PEG) allergy could not be unequivocally excluded in the patients' history. Forty-one patients (38 females, 3 men, age 51 +/- 17.7) were tested on 3 days. The average contact time needed per patients for the nurse was 30 minutes and for the physician 25 minutes. One patient could not be tested due to antihistamine use. After testing, in 36 cases routine vaccination was recommended;of those 35 patients got vaccinated. In four patients, an indication for inpatient PEG provocation or inpatient vaccination was given. Two thirds (27/41 patients, 65.9%) of all who were initially refusing vaccination got vaccinated shortly after allergy tests and tolerated this vaccination without major complications, an additional 9.8% intended future vaccination. Only four patients (9.8%) persistently refused vaccination after testing. Conclusion(s): In this pilot study, we show a useful and effective option to triage patients requesting COVID-19 vaccine allergy testing and generally how to process allergy appointments in a more time effective manner. Optimizing intraclinical processes leads to a substantially higher number of patients that can be allergy tested and vaccinated. Copyright © 2022 Dustri-Verlag Dr. K. Feistle.

Utilization of Allergy and Immunology Services Among Rescue Workers Exposed to the World Trade Center Disaster

RATIONALE: Over 400,000 individuals are estimated to have been exposed to the fallout of the World Trade Center (WTC) disaster. The incidence of acquired allergy and lung injury among rescue and cleanup workers exposed to the WTC fallout has been established. Briefly, rescue and cleanup workers exposed to the WTC fallout had a high incidence of allergic hypersensitivity and permanent small airways dysfunction characterized by distal airways narrowing and airway hyperresponsiveness. The current study sought to quantify the utilization of allergy/immunology services among rescue and cleanup workers exposed to the WTC fallout. METHODS: Subjects (N=65) were referred from the WTC Health Program to a multispecialty allergy/immunology and pulmonology clinic for provision of allergy-immunology specialty services. Electronic health records of all subjects were retrospectively reviewed from the date of first referral to March 2020-when routine care was interrupted due to the coronavirus disease 2019 pandemic-to quantify utilization of allergy/immunology and pulmonology services;10 subjects were excluded from analysis due to incomplete health records. RESULTS: On average, time to referral for allergy-immunology services by the WTC Health Program was 15.2 years (SD=1.7). The majority of the subjects were male (89.1%), police officers (67.3%) who never smoked (65.5%) and had no history of allergic or respiratory disease prior to being exposed to the WTC fallout. Most were found to have environmental allergies (83.6%);the most common comorbidities were allergic rhinitis (89.1%), asthma (67.3%), and chronic sinusitis (63.6%). All subjects underwent environmental allergy testing. Most subjects-35 of 55 (63.6%)-were prescribed an epinephrine autoinjector for environmental allergies. Regarding allergic immunotherapy (IT), 33 of 55 (60.0%) received IT;additionally, 7 subjects (12.7%) were determined to be IT candidates but did not receive IT. The most common monoclonal antibody therapy used in this cohort was omalizumab (18.2%). Only 11 (20.0%) and 3 (5.5%) underwent serum IgE and IgG testing, respectively. CONCLUSION: Rescue and cleanup workers referred to a multispecialty allergy/immunology and pulmonology practice from the WTC Health Program not only had a high incidence of acquired allergies to environmental allergens, but the majority were prescribed and epinephrine autoinjector and either received or were candidates to receive allergy immunotherapy. Given that hundreds of thousands of individuals were exposed to the WTC fallout and exposure is an independent risk factor for developing allergic disease, this research may have identified ways we may be falling short in providing allergy/immunology services to exposed individuals.

KOUNIS SYNDROME TYPE 2: A COLD CASE

Case Report: A 61-year-old man, smoker and family history of cardiovascular diseases, started oral antibiotic therapy with amoxicillin / clavulanic acid following the appearance of a dental abscess. About 30 minutes after taking the antibiotic, he complained of widespread erythema in the limbs, followed by intense itching and dyspnea. Upon arrival of the medical staff, IV cortisone and antihistamine therapy was performed with gradual and progressive resolution of the symptoms. Despite the doctors' invitation, the patient refused access to the emergency room for fear of a possible hospital infection with SARS-CoV-2. Almost two months later, due to the onset of exertional dyspnea, he is persuaded to go to the hospital for further tests. The ECG showed signs of diffuse anterolateral necrosis (Figure 1). Echocardiography showed severe left ventricular dysfunction (FE 35%) with extensive akinesia of the mid-distal SIV, apex, and anterior mid-distal wall. Myocardiocytolysis indices were negative and allergy tests positive for beta-lactam antibiotics. Subsequently he underwent coronary angiography which showed proximal occlusion of an intermediate branch (Figure 2) treated with angioplasty and drug stent release. Cardiac MRI was then performed with evidence of a large area of ischemic necrosis (subendocardial / transmural) of the antero-septal, anterior and anterolateral wall with FE 35% (Figure 3). Comment: Kounis syndrome is a clinical emergency characterized by the appearance of an acute coronary syndrome during an anaphylactic-type reaction. A correct diagnosis is of fundamental importance to limit the extent of myocardial damage as much as possible. In Kounis type 2, the mediators of the allergic reaction can cause not only vasospasm but also the activation of metalloproteases that induce the degradation of collagen with consequent rupture of pre-existing atheromatous plaques, as in our patient. Failure to perform an ECG during first aid leaves doubts about the possible allergic genesis of the episode, which however cannot be excluded with certainty. We have decided to report this clinical case to emphasize the importance of always taking into consideration the possibility of being compared with a case of Kounis when assisting a patient with an anaphylactic type reaction. (Figure Presented).

Improving Antimicrobial Stewardship through Allergy Testing Referrals

Background. Penicillins and cephalosporins (PCN/CEPH) are considered firstline antibiotics for numerous infections for their efficacy, tolerability, and cost effectiveness. Unfortunately, their use may be precluded in approximately 10% of the general adult population who self-report 'allergy'. As a result, suboptimal antimicrobials are substituted which may increase toxicities, length of hospitalizations, and antimicrobial resistance with subsequent expense and morbidity. Multiple organizations endorse beta-lactam allergy skin testing (BLAST) as an essential component of antimicrobial stewardship programs.In an attempt to better describe this patient population as well as to protocolize and improve rates of referral to allergy/immunology clinic, a quality initiative was undertaken at our institution. Methods. Adult inpatients for whom an infectious disease consult was placed over a 6-month period were chart-reviewed for PCN/CEPH allergy. Inappropriately charted allergies were reconciled and patients were recommended referral to allergy/immunology for formal evaluation with BLAST when appropriate. Referrals were placed for agreeable patients who were then evaluated for appropriateness through history and then scheduled for BLAST. Patients who tolerated oral exposures without adverse effects had the allergy removed from their chart and were educated. Results. 322 patients met inclusion criteria for allergy referral. Of those, 103 agreed to further evaluation, and referrals were placed for 100%. Unfortunately, 7 patients died before referrals could be completed, and 88 referred patients did not complete BLAST for other reasons. In total 8 patients completed BLAST, and allergy was de-labeled in 75% (N= 6) of those cases. Conclusion. Our data indicated similar prevalence of reported PCN/CEPH allergy between our institution and the general population. We achieved our aim of improving allergy referral rates among this population, however there was a high rate of attrition in the transitions of care. Qualitative review of selected patients highlights common thematic barriers including the COVID-19 pandemic, fiscal concerns, and acuity of condition. Future directions should include BLAST at the point of care or making referrals from the primary care setting.

Beware excipients: Anaesthetic considerations for a patient with metabisulphite allergy

Allergy to excipients used in drug formulations is an often overlooked issue, recently highlighted by cases of severe reaction to the Pfizer-Biontech COVID-19 vaccination. Sulphites, including metabisulphites, are antioxidant preservatives found in many foods but also in certain drugs used by anaesthetists, including metaraminol, catecholamines, metoclopramide and some forms of propofol. Patients may present with a variety of intolerances to sulphites. Anaesthetists need to know how to counsel them, which drugs to avoid, and whether to administer sulphite-containing adrenaline in an emergency scenario. Description A patient with reported sulphite allergy following previous reactions to metabisulphite-containing local anaesthetic presented for an elective operation. The hospital pharmacist took several weeks to confirm the sulphite content of key anaesthetic drugs and to find alternatives. In particular, sulphite-free adrenaline had to be sourced from France. General anaesthesia proceeded uneventfully, and a 'green bag' of safe emergency drugs stayed with the patient until her discharge. The patient was referred for further allergy testing, but as the allergy centre could not provide sulphite-free adrenaline, she declined challenge with metabisulphites and with preparations of adrenaline available in the UK. This will clearly pose a challenge in the future should she present with anaphylaxis or for emergency surgery or critical care. Discussion Documented reactions to parenteral sulphites are uncommon, varied and cover a variety of suggested pathophysiologies, of which IgE-mediated allergy is rare [1]. Additionally, asthmatics may report bronchospasm related to sulphite containing foodstuffs, but this results from direct irritation from sulphur dioxide and is not immune mediated. Establishing the diagnosis is difficult, requiring challenge testing in specialist allergy centres;skin prick testing can be unreliable. Challenge with sulphite-containing adrenaline, thus establishing safety of use in case of anaphylaxis, is one pragmatic option. Sensible precautions include close liaison with the hospital pharmacist, an easily accessible list of sulphite-free alternatives and a policy on adrenaline use in anaphylaxis. Although evidence is scant, expert opinion suggests that in anaphylaxis the benefit of administering sulphite-containing adrenaline outweighs the risks [2].

Allergies and COVID-19 vaccines: An ENDA/EAACI Position paper.

BACKGROUND: Anaphylaxis, which is rare, has been reported after COVID-19 vaccination, but its management is not standardized. METHOD: Members of the European Network for Drug Allergy and the European Academy of Allergy and Clinical Immunology interested in drug allergy participated in an online questionnaire on pre-vaccination screening and management of allergic reactions to COVID-19 vaccines, and literature was analysed. RESULTS: No death due to anaphylaxis to COVID-19 vaccines has been confirmed in scientific literature. Potential allergens, polyethylene glycol (PEG), polysorbate and tromethamine are excipients. The authors propose allergy evaluation of persons with the following histories: 1-anaphylaxis to injectable drug or vaccine containing PEG or derivatives; 2-anaphylaxis to oral/topical PEG containing products; 3-recurrent anaphylaxis of unknown cause; 4-suspected or confirmed allergy to any mRNA vaccine; and 5-confirmed allergy to PEG or derivatives. We recommend a prick-to-prick skin test with the left-over solution in the suspected vaccine vial to avoid waste. Prick test panel should include PEG 4000 or 3500, PEG 2000 and polysorbate 80. The value of in vitro test is arguable. CONCLUSIONS: These recommendations will lead to a better knowledge of the management and mechanisms involved in anaphylaxis to COVID-19 vaccines and enable more people with history of allergy to be vaccinated.

Early results of an in vivo and in vitro allergy testing protocol for COVID-19 vaccinations

Introduction: Mechanisms underlying allergic reactions to the new BNT162b2 (Pfizer) and AZD1222 (AstraZeneca) COVID-19 vaccinations are poorly understood. Polyethylene glycol (PEG) is implicated for BNT162b2;and polysorbate 80 (PS80) and disodium edetate (EDTA) for AZD1222. Methods: Patients referred to our service were investigated with standardised vaccine skin-prick testing (SPT) and intradermal testing (IDT) protocols. Basophil activation testing (BAT) was performed in patients with history highly suggestive of excipient or vaccine allergy. Results: Reason for referral was suspected excipient allergy in 16/23 (70%), previous other vaccine reaction in 4/23 (17%), and reaction to the BNT162b2 vaccine in 3/23 (13%). In patients with suspected excipient allergy, SPT was only positive in 1/16 (6%). In 12/16 patients with suspected PEG allergy, IDT and BAT were positive in 5 (42%) for the BNT162b2 vaccine but not PEG. 3/5 have subsequently undergone successful vaccination with AZD1222, while 1/5 had cross-reactivity with AZD1222 on BAT and has not been vaccinated. 2/16 patients with suspected PS80 allergy were negative on SPT, IDT, and BAT, and have undergone successful AZD1222 vaccination. In the 2/16 patients with EDTA allergy IDT was positive to EDTA but neither vaccine, correlating with BAT. 1 has been successfully vaccinated with the EDTA-containing AZD1222 vaccine. 2 patients (1 reaction to BNT162b2, 1 other vaccine reaction) developed systemic reactions during testing without tryptase elevation. Both were associated with local flare response to the BNT162b2 vaccine, both have undergone successful vaccination with the AZD1222 vaccine. All other patients with negative SPT, IDT, and BAT results have subsequently tolerated vaccination. Conclusion: Most patients can be successfully vaccinated with available COVID-19 vaccines. SPT has low sensitivity and a combined protocol of SPT, IDT, and BAT provides confidence in allergy delabelling. Not all excipient allergies correlate to vaccination allergy and BAT provides a powerful diagnostic tool in these cases.

The clinical and cost effectiveness of telemedicine consultation in tertiary paediatric allergy during the COVID-19 pandemic: A comparative study

Background: The COVID-19 pandemic has enhanced the growth of telemedicine in an unexpected speed. Our study compares the service and cost effectiveness of telephone clinics (TC) to standard face to face clinics (FTFC) in the paediatric allergy service. Method: This retrospective study looked into paediatric allergy clinic activities from April 1-October 1, 2020 in the Great North Children Hospital, Newcastle. We also collected data from standard FTFCs in the pre-COVID period as comparative group. Clinic activities were reviewed by looking into patients' clinic notes and letters. Results: Clinic attendance rate in both groups was similar (91%, 94%). 9% of the patients were not available at the time of TC appointment. Majority did not answer but 4 consultations were discontinued due to language barrier. Up to 73% of patients did not have allergy tests after TC, despite being clinically indicated in half of them. Serum IgEs (sIgE) has become the preferable diagnostic option in TC. The median of sIgEs ordered per patient is 7 in TCs, as compared to 6 in control (p < 0.05). This has resulted in a 20% increase in laboratory cost. Clinic discharge rate is higher in FTFC (41%) as compared to TC (25%). The average follow-up time interval after TC is shorter than FTFC, 7.6 months and 9.4 months respectively (p < 0.05). More regular follow-ups in TC group has led to an increase of average clinician follow-up cost per patient by 32%. Conclusion: A telemedicine-based allergy service model can be more time-effective and improve patient access to specialist care, only with well-designed framework and planning. Screening criteria for selecting suitable TC patients can be the key to success. We present an example of recommended screening criteria based on patients' diagnosis and certain special circumstances. (Figure Presented).

COVID-19 vaccines: An allergological study

Background: In order to prevent infection with severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) an active approach is necessary. On December 2020 the commercialization of the COVID-19 vaccines was made. In Spain the first one to arrive was Pfizer-BioNtech vaccine. Initially, several reports of anaphylactic reactions due to the vaccine in the USA and in the UK were reported, which lead to an early recommendation to avoid the administration in patients with allergic history. The objective of this study is to describe and characterize the allergenic profiles of patients attended in our clinic for allergy testing to prevent reactions with the COVID-19 vaccine. Method: The allergological profile of 85 patients diagnosed with previous history of allergic disorders was analysed between January 18th and March 16th 2021. The allergological study included skin-prick test with polyethylene glycol (PEG), Tween 20, Tween 80, and COVID-19 vaccine (Pfizerâ), together with latex and other allergens when necessary. After the double dose of vaccine was completed, a follow up was done by telephone. Results: Risk stratification and approach is exposed in figure 1. Clinical and allergological characteristics of 85 patients are shown in table 1. Out of them, 88.2% had an allergic comorbidity and 48.2% had drug allergy. The reason for consultation was in 92.9% due to their allergic history, 76.5% were referred from the Occupational Health Service, and 80.6% of the patients have had previous vaccination with other anti-infective vaccines without reactions. Also, table 1 shows the prick-test results with COVID vaccine an its excipients, without any positive result. 70.7% of our population has completed the vaccination. Only 9 patients had a possible allergic reaction to the first dose, 8 of them had cutaneous and the remaining had respiratory symptoms. Out of these 9 patients, 6 had their second dose without any symptoms. Conclusion: None of the patients studied showed a positive test for neither the components of the vaccine nor the vaccine itself. More studies are required with a larger sample size to reach final conclusions. (Table Presented).