Telitacicept for systemic lupus erythematosus with post‑surgical papillary thyroid carcinoma: A case report

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a complex etiology primarily linked to abnormalities in B lymphocytes within the human body, resulting in the production of numerous pathogenic autoantibodies. Telitacicept is a relatively novel humanized, recombinant transmembrane activator, calcium modulator and cyclophilin ligand interactor fused with the Fc portion (TACI-Fc). It works by competitively inhibiting the TACI site, neutralizing the activity of B-cell lymphocyte stimulator and A proliferation-inducing ligand. This, in turn, inhibits the development and survival of plasma cells and mature B cells. A 28-year-old female was admitted to the Department of Rheumatology and Immunology (People's Hospital of Longhua; Shenzhen, China) in June 2021 due to systemic edema for more than a month and hair loss lasting for a week. After comprehensive examination, the patient was diagnosed with SLE with hematological system involvement, serositis, lupus nephritis and secondary antiphospholipid syndrome. After receiving medications including glucocorticoids, mycophenolate mofetil and cyclosporine, the patient's white blood cells, platelets, hemoglobin, urinary protein and multiple serositis returned to normal. However, the levels of complement 3 (C3) and C4 did not significantly improve. Subsequently, the patient underwent thyroid ultrasound examination, which suggested thyroid nodules. After thyroid puncture biopsy, the patient was diagnosed with papillary thyroid carcinoma (PTC). After surgical resection, the patient was confirmed to have PTC by pathological biopsy, with no lymph node metastasis. At two months after surgery, the patient was treated with telitacicept, and the complement levels not only returned to normal but also remained stable for a long time. The present case was the first to report the use of telitacicept for the successful treatment of a patient with SLE with post-surgical PTC, providing a potential therapeutic option for SLE with a prior history of carcinoma. The role of telitacept in this field requires further research and attention.