Background This systematic review used the GRADE approach to compile evidence to inform an anaphylaxis guideline from the European Academy of Allergy and Clinical Immunology (EAACI). Methods We searched five bibliographic databases from 1946 to 20 April 2020 for studies about the diagnosis, management and prevention of anaphylaxis. We included 50 studies with 18,449 participants: 29 randomised controlled trials, seven controlled clinical trials, seven consecutive case series and seven case-control studies. Findings were summarised narratively because studies were too heterogeneous to conduct meta-analysis. Results It is unclear whether the NIAID/FAAN criteria or Brighton case definition are valid for immediately diagnosing anaphylaxis due to the very low certainty of evidence. Adrenaline is the cornerstone of first-line emergency management of anaphylaxis but, due to ethical constraints, little robust research has assessed its effectiveness . Newer models of adrenaline autoinjectors may slightly increase the proportion of people correctly using the devices and reduce time to administration. Face-to-face training for laypeople may slightly improve anaphylaxis knowledge and competence in using autoinjectors. Adrenaline prophylaxis prior to snake bite anti-venom may reduce anaphylaxis but the impact of prophylactic corticosteroids and antihistamines is uncertain. There was insufficient evidence about the impact of other anaphylaxis management strategies. Conclusions Anaphylaxis is a potentially life-threatening condition but, due to practical and ethical challenges, there is a paucity of robust evidence about how to diagnose and manage it.
Introduction: Polyethylene glycols (PEGs) are widely used as excipients in drugs, cosmetics and household products. Immediate-type allergy to PEGs including anaphylaxis are reported with low but increasing frequency. Low awareness of the allergenic potential of PEGs among consumers, manufacturers and doctors leads to under-diagnosis and under-reporting of PEG allergy, putting patients at risk of repeated severe reactions. The aims of this study were to investigate clinical manifestations, time to diagnosis and impact of a PEG allergy diagnosis on daily life of patients. Method: Ten PEG allergic patients answered a questionnaire about clinical manifestations, causes and impact on daily life of a PEG allergy, scored on a likert scale (0-10) before and after diagnosis. Results: Eight patients had experienced at least one anaphylactic reaction requiring adrenaline treatment. Anaphylaxis was caused by depot-steroids, antibiotic/analgesic tablets, antacids and laxatives. Seven patients reported repeated reactions before diagnosis (median 3, range 2-6). Median time from first reaction to diagnosis was 20 months (range 2-120). None of the patients experienced severe allergic reactions after the diagnosis. Median likert score of the impact on daily life before diagnosis was 7 compared to 4 after diagnosis. Conclusion: Daily life of PEG allergic patients is improved after diagnosis. Detailed information about the allergy, an allergy warning card, education in checking labels of new products, continued follow-up and advice from the Allergy Department were reported by patients to be important. Improved awareness about PEG allergy, clear product labelling and a standardized nomenclature is needed to improve care for these patients.