Severe allergic systemic reaction to personal protective equipment during the COVID-19 pandemic.

Our case describes a hospital worker who suffered a severe reaction to personal protective equipment (PPE) during the COVID-19 pandemic. After researching the excipient list of her PPE and completing a literature review, we postulated that isocyanates used in the production of the polyurethane band of the N95 mask was the cause for her reaction. In the absence of standardised testing, we tested this hypothesis by replicating her reaction to PPE by using a commercially available isocyanate patch, identifying diphenylmethane-4, 4-diisocyanate as the culprit agent.We recommended caution in the use of polyurethane containing N95 masks- for people reporting allergic reaction- and testing for sensitivity for polyurethane. The patient was able to tolerate non-polyurethane containing standard surgical masks, providing an option for PPE in some clinical circumstances. Since avoiding N95 masks, she has not had any further reactions.