LAUSR

OBJECTIVES This study was conducted to investigate factors involved in anaphylaxis related to diclofenac etalhyaluronate (DEH) [product name: Joyclu® (JCL)] (containing DEH and macrogol 400), which is used to treat patients with osteoarthritis. METHODS Patients with osteoarthritis were divided into two groups that had (experienced patients) or had not experienced anaphylactic symptoms after JCL administration (non-experienced patients). Five tests performed to assess factors related to anaphylaxis consisted of a skin prick test (SPT) as the primary endpoint and the other tests including basophil activation test, allergen-specific IgE (sIgE) tests using enzyme-linked immunosorbent assay or immunochromatographic kits, and genetic study were secondary endpoints. RESULTS The SPT showed 4 (wheal)/7 (erythema) of 15 experienced patients and 0/3 of 19 non-experienced patients were positive for any of the test reagents containing DEH. The basophil activation test showed two experienced patients were positive for test reagents containing DEH. DEH- and diclofenac-sIgE were detected in 3 and 1 of 12 experienced patients, respectively. No clear results were shown in the other tests. CONCLUSIONS DEH may be the main factor involved in the development of anaphylaxis. The SPT was more sensitive than the basophil activation and allergen-sIgE tests for identifying factors associated with anaphylaxis.