[Desensibilización a Rituximab en paciente con proteinuria persistente secundaria a LES].

Introduction: Rituximab is an Anti-CD20 chimeric monoclonal antibody, being the treatment of lymphoproliferative diseases and rheumatological disorders; hypersensitivity reactions (HRS) are associated with infusion, cytokine release, type I (IgE/non-IgE), mixed, type III and IV. Desensitization seeks to induce tem- porary tolerance, decreasing the probability of clinical manifestations through gradual administration of the total dose of the drug, being target cells of the procedure, basophils, and mast cells, preventing their activation.

Case report: The objective is to present a personalized desensitization protocol in a 36-year-old female patient with systemic lupus erythematosus (SLE) pre- viously treated with rituximab in 2019, 4 doses, presenting during the fourth administration, after 10 minutes, dyspnea, feeling foreign body in the pharynx, chest pain, angioedema, and neurological alteration. Requiring new administration of rituximab due to persistent proteinuria secondary to SLE. After performing skin tests (negative), a 13-step desensitization scheme was performed with 3 concentrations (solution: A [1:100], B [1:10] and C [1:1]). Since only 52% of RHS to rituximab are positive in skin tests and given the degree of reaction (serious), desensitization is decided, based on reactions presented by patient and clinical context. Achieving a cumulative dose of 897.87 mg in a period of 5 hours, without reactions during or after the procedure, concluding successfully.

Conclusion: By carrying out desensitization protocols, the administration of a drug is allowed, offering a safe therapeutic option, when this is the treatment of choice in previously sensitized patients, offering an alternative when the benefits outweigh the risks of its administration.