House dust mite allergen avoidance strategies for the treatment of allergic asthma:A hypothesis-generating meta-analysis

Background: This study continues the review by Gøtzsche and Johansen (Cochrane Database of Systematic Reviews, 2008, Art. No: CD001187), aiming to systematically generate hypotheses on the effectiveness of (sub)strategies for house dust mite allergen avoidance in the treatment of allergic asthma. Methods: We used the trials previously analysed by Gøtzsche and Johansen and searched recently published studies. Data on asthma symptom scores (ASS), ACQ, number of improved patients, AQLQ-scores, medication use, FEV1%, PC20, and FeNO levels were analysed. The effectiveness of strategies was assessed using Metafor in R. Results: Thirty-five trials involving 2419 patients were included in the final study. The patient-reported outcome number of patients with improved condition following total bedroom control was RR = 3.39 (95% confidence interval: 1.04 to 11.04, P = 0.04). The mean differences in the ASS by nocturnal air purification was −0.7 (95% confidence interval: −1.08 to −0.32, P &lt; 0.001). Other outcomes including partial bedroom control were non-significant or clinically not of importance. Conclusions: Total bedroom control and nocturnal air purification of the breathing zone hypothetically provides clinical benefits in patients with house dust mite-induced allergic asthma. The number of patients with improvements in their condition respectively the asthma symptom score differences showed potential in small subgroups, consisting of single studies. Partial bedroom control is not recommended. Systematic Review Registration: Prospero CRD42022323660.</p

Characteristics of COVID-19 infection and antibody formation in patients known at a tertiary immunology department

Background: Knowledge about COVID-19 infections is expanding, although knowledge about the disease course and antibody formation in patients with an auto-immune disease or immunodeficiency is not fully unraveled yet. It could be hypothesized that immunodeficient patients, due to immunosuppressive drugs or their disease, have a more severe disease course due to their immunocompromised state. However, it could also be hypothesized that some of the immunosuppressive drugs protect against a hyperinflammatory state. Methods: We collected data on the incidence of COVID-19, disease course and SARS-CoV-2 antibody formation in COVID-19 positive patients in a cohort of patients (n ​= ​4497) known at the Clinical Immunology outpatient clinic in a tertiary care hospital in the Netherlands. Results: In the first six months of the pandemic, 16 patients were identified with COVID-19, 14 by nasal swab PCR, and 2 pa

Homemade Food Allergen Extracts for Use in Skin Prick Tests in the Diagnosis of IgE-Mediated Food Allergy: A Good Alternative in the Absence of Commercially Available Extracts?

Introduction: The skin prick test (SPT) is the first step in the diagnosis of an immuno-globulin E (IgE)-mediated food allergy. The availability of commercial food allergen extracts is very limited, resulting in a need for alternative extraction methods of food allergens. The objective of this study was to compare the SPT results of homemade food allergen extracts with commercially available extracts. Methods: Adult patients with a suspected food allergy were included. Food allergen-specific symptoms were scored using a questionnaire. SPTs were performed with homemade and commercially available extracts (ALK-Abelló, Kopenhagen, Denmark) from almond, apple, hazel-nut, peach, peanut, and walnut. Serum-specific IgE was measured with ISAC or ImmunoCAP™. Intra-class correlation coefficients (ICC) between the SPT results of both extract methods were cal-culated. The proportion of agreement with food allergen-specific symptoms was analyzed. Results: Fifty-four patients (mean age 36; range 19–69 years; female/male: 42/12) were included. The intra-class correlation coefficient (ICC) between the SPT results of both extract methods were strong for hazelnut 0.79 (n = 44) and walnut 0.78 (n = 31), moderate for apple 0.74 (n = 21) and peanut 0.66 (n = 28), and weak for almond 0.36 (n = 27) and peach 0.17 (n = 23). The proportion of agreement between SPT results and food allergen-specific symptoms was comparable for homemade and commercially available extracts, except for peach; 0.77 versus 0.36, respectively. Conclusion: In the diagnostic pro-cedures to identify an IgE-mediated food allergy, homemade extracts from hazelnut and walnut appear to be a good alternative in the absence of commercially available food allergen extracts

Small percentage of anaphylactic reactions treated with epinephrine during food challenges in Dutch children

Background: Severe allergic reactions, including anaphylaxis, occur during oral food challenges (OFCs) and the first-line treatment of anaphylaxis is epinephrine. Objective: To evaluate the percentage of anaphylactic reactions treated with epinephrine during OFCs and to identify associated factors for the administration of epinephrine. Methods: Children who underwent an OFC with peanut, hazelnut, cow's milk, hen's egg, or cashew nut from 2005 through 2015 in the Netherlands were evaluated. Children with reactions meeting the criteria for anaphylaxis according to the European Academy of Allergy and Clinical Immunology guidelines for food allergy and anaphylaxis were included. Children with an anaphylactic reaction treated with vs without epinephrine were compared. Possible factors associated with the administration of epinephrine, such as age, sex, symptoms consistent with asthma, history of an allergic reaction to the tested allergen, and symptom types during the anaphylactic reaction, were evaluated using logistic regression analysis. Results: Eighty-three children in clinical and research settings (43% boys; median age, 7 years; range, 1-17) who met the criteria for anaphylaxis were included in this study. Thirty-two of 83 children (39%) with anaphylaxis were treated with epinephrine. Respiratory symptoms during the OFC were treated significantly more often with epinephrine than gastrointestinal symptoms (P = .01). Conclusion: Only 39% of children with anaphylaxis, according to the guideline criteria, were treated with epinephrine during the OFC and most of these children had respiratory symptoms. There is need for an easy-to-use international guideline for the treatment of allergic symptoms during OFCs

Small percentage of anaphylactic reactions treated with epinephrine during food challenges in Dutch children

Background: Severe allergic reactions, including anaphylaxis, occur during oral food challenges (OFCs) and the first-line treatment of anaphylaxis is epinephrine. Objective: To evaluate the percentage of anaphylactic reactions treated with epinephrine during OFCs and to identify associated factors for the administration of epinephrine. Methods: Children who underwent an OFC with peanut, hazelnut, cow's milk, hen's egg, or cashew nut from 2005 through 2015 in the Netherlands were evaluated. Children with reactions meeting the criteria for anaphylaxis according to the European Academy of Allergy and Clinical Immunology guidelines for food allergy and anaphylaxis were included. Children with an anaphylactic reaction treated with vs without epinephrine were compared. Possible factors associated with the administration of epinephrine, such as age, sex, symptoms consistent with asthma, history of an allergic reaction to the tested allergen, and symptom types during the anaphylactic reaction, were evaluated using logistic regression analysis. Results: Eighty-three children in clinical and research settings (43% boys; median age, 7 years; range, 1-17) who met the criteria for anaphylaxis were included in this study. Thirty-two of 83 children (39%) with anaphylaxis were treated with epinephrine. Respiratory symptoms during the OFC were treated significantly more often with epinephrine than gastrointestinal symptoms (P = .01). Conclusion: Only 39% of children with anaphylaxis, according to the guideline criteria, were treated with epinephrine during the OFC and most of these children had respiratory symptoms. There is need for an easy-to-use international guideline for the treatment of allergic symptoms during OFCs

The Dutch Working Party on Antibiotic Policy (SWAB) guideline for the approach to suspected antibiotic allergy

Objectives: Prudent handling of reported antibiotic allergies is an important aspect of antibiotic stewardship. The Dutch Working Party on Antibiotic Policy (SWAB) constituted a multidisciplinary expert committee to provide evidence-based recommendations for bedside decision-making in antibiotic therapy in patients that report an antibiotic allergy. Methods: The guideline committee generated 12 key questions, most of which were population, intervention, comparison, and outcome questions relevant to both children and adults with suspected antibiotic allergies. For each question, a systematic literature search was performed and reviewed for the best available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The quality of evidence was graded from very low to high, and recommendations were formulated in structured discussions as strong or weak. Results: Sixty recommendations were provided for suspected allergy to β-lactam antibiotics (BLAs) and non–β-lactam antibiotics. Owing to the absence of randomized controlled trials in this field, the underlying evidence was predominantly graded as low or very low. Available data support that a detailed allergy history should always be performed and critically appraised. When cross-allergy between BLA groups is not to be expected due to the absence of molecular similarity of the side chains, the patient can be safely exposed to the alternative BLA. An exception to this rule is severe delayed-type reactions in which re-exposure to a BLA should only be considered after consultation with a multidisciplinary team. Conclusions: Accumulated scientific data now support a more liberal approach that better balances the benefits of treatment with first choice and usually smaller spectrum antibiotics with appropriate avoidance of antibiotics in case of a truly high risk of a (severe) allergic reaction. In The Netherlands, a formal guideline was developed that provides recommendations for the approach toward suspected allergy to BLA and frequently used non–β-lactam antibiotics, thereby strongly supporting antimicrobial stewardship