hematol transfus cell ther. 2 0 2 1; 4 3(1) :9–14 www.htct.com.br Hematology, Transfusion and Cell Therapy Original article Allergic reactions to asparaginase: retrospective cohort study in pediatric patients with acute lymphoid leukemia Ana Paula Battistel a,* , Bruno Simas da Rocha a , Maitê Telles dos Santos a , Liane Esteves Daudt b,c , Mariana Bohns Michalowski a,c,d a Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil b Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Porto Alegre, RS, Brazil c Departamento de Pediatria, Faculdade de Medicina, Universidade Federal do Rio Grande do Sul (UFRGS) Porto Alegre, RS, Brazil d Centro de Pesquisa Experimental (CPE), Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil a r t i c l e i n f o Article history: Received 27 June 2019 Accepted 20 November 2019 Available online 22 January 2020 Keywords: Acute lymphoblastic leukemia Asparaginase Hypersensitivity Children a b s t r a c t Introduction: To assess the frequency of allergic reactions to asparaginase (ASP) and possible risk factors for reactions in a cohort of pediatric patients. Method: The study was performed based on retrospective data from patients under acute lymphoid leukemia treatment in a general university hospital located in southern Brazil. Information on patients who used ASP from 2010 to 2017 was collected. Allergic reactions were identified in electronic medical records. Results: Among the 98 patients included in the study, 16 (16.3 %) experienced an allergic reaction to native l-asparaginase (L-ASP). Of the 22 patients (22.4 %) that received only intra- venous (IV) administration of l-ASP, 10 (62.5 %) had allergic reactions, while 48 patients (49 %) received intramuscular (IM) administration and 28 (28.6 %) received IV and IM adminis- trations. The occurrence of allergic reactions differed between the groups (p < 0.001), and IV administration was associated with allergic reactions. Association was also observed between the severity of the reaction and the route of administration, with the IM route associated with grade 2 and IV route associated with grade 3. Occurrence of allergic reac- tions was higher when the commercial formulation of l-ASP, Leuginase ® , was used (p = 0.0009 in the analysis per patient and p = 0.0003 in the analysis per administration). Conclusions: The IV administration and commercial Leuginase ® presentation were associ- ated with more allergic reactions in the study population, which corroborates the findings in the literature. The IV route was also associated with higher severity of reactions in the present study. © 2020 Associac¸˜ ao Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). * Corresponding author at: Hospital de Clínicas de Porto Alegre. Rua Ramiro Barcelos, 2350, Porto Alegre, RS CEP 90035-903, Brazil. E-mail address: apbattistel@gmail.com (A.P. Battistel). https://doi.org/10.1016/j.htct.2019.10.007 2531-1379/© 2020 Associac¸˜ ao Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).