C A S E R E P O R T EUR ANN ALLERGY CLIN IMMUNOL Summary Piperacillin is a beta-lactam antibiotic of penicillin family. Some penicillins were reported as occupational diseases cause, but piperacillin anaphylaxis with occupational sensitization is rare. We describe the case of a female nurse with recurrent anaphylaxis in last few months without apparent cause, only in work environment. Latex allergy was excluded after negative latex glove provocation. Later during diagnostic workup, the patient reported a similar reac- tion minutes after piperacillin preparation. She denied any previous antibiotic therapeutic exposure. Skin prick tests (SPT) to beta-lactams were positive to piperacillin, penicillin G and major and minor determinants. SPT to cefuroxime was negative but intradermic test was positive. The patient has indication for beta-lactams eviction and for adrenaline auto-injector kit. No further reactions occurred after patient’s transfer to another department with mini- mum possible exposure. Allergic risk prevention is essential and must be rapidly implemented to avoid incapacitating occupational diseases development. Corresponding author João Gaspar-Marques Serviço de Imunoalergologia Hospital de Dona Estefânia Centro Hospitalar de Lisboa Central, EPE Rua Jacinta Marto, 1169-045 Lisbon, Portugal Phone: +35 121 312 6653 Fax: +35 121 312 6654 E-mail: gasparmarques@yahoo.com.br Doi 10.23822/EurAnnACI.1764-1489.29 KEY WORDS anaphylaxis; beta-lactams; drug hypersensitivity; occupational diseases; piperacillin 1 Serviço de Imunoalergologia, Hospital de Dona Estefânia, Centro Hospitalar de Lisboa Central, Lisbon, Portugal 2 CEDOC, Faculdade de Ciências Médicas (FCM), Universidade Nova de Lisboa, Lisbon, Portugal J. GASPAR-MARQUES 1,2 , E. FINELLI 1 , P.C. MARTINS 1,2 , S. PRATES 1 , P. LEIRIA-PINTO 1,2 Piperacillin-tazobactam anaphylaxis: a rare cause of occupational disease Introduction Anaphylaxis is a rapid-onset, multisystem hypersensitivity reac- tion with potentially fatal outcome (1). Clinically, anaphylaxis most frequent manifestations are cutaneous; however, respira- tory, cardiovascular, gastrointestinal, and other symptoms may also occur (1). Drug-induced anaphylaxis (DIA) hypersensitiv- ity mechanism is mainly an IgE-mediated response, but others have been characterized (1). Penicillin was in the past DIA most frequent cause, but was recently surpassed by amoxicillin (1). Healthcare professionals (HCP) are exposed to a large number of substances that act as allergens and/or irritants (2). These al- lergenic substances were known to cause contact dermatitis, but nowadays a wide spectrum of clinical manifestations like asth- ma, rhinitis, conjunctivitis and anaphylaxis is also included (2). Piperacillin is an extended-spectrum beta-lactam antibiotic of the ureidopenicillin family, commonly used in combination with tazobactam, a beta-lactamase inhibitor. Some penicillins have been reported to cause occupational diseases (3-7), but only one case of piperacillin anaphylaxis with occupational sensitization has been described, and the diagnosis was only supported by serum IgE antibody detection (8). The authors describe the first case report of piperacillin anaphylaxis with oc- cupational sensitization and diagnosis confirmed by skin tests. Case report A 28 year-old female nurse, with previous rhinitis history, was referenced to our outpatient clinic due to, in the last few months, recurrent episodes of generalized pruritus and cuta- VOL 50, N 2, 89-91, 2018