A telitacicept routine (160 mg, qw) was also added (seeFigure3)

A telitacicept routine (160 mg, qw) was also added (seeFigure3). == Physique1. renal function improved significantly within a short period of time, and his hearing and lung lesions improved significantly. At the same time, he did not develop serious infections and other related complications. Our report suggests that short-term control of the patients conditions is necessary in GPA patients with organ-threatening disease. Telitacicept combined with CYC and glucocorticoids may be an induction therapy with safety and feasibility. However, more clinical trials are needed to validate the efficacy and safety of the therapeutic Tolrestat regimen. Keywords:granulomatous polyangiitis, rapidly progressive glomerulonephritis, telitacicept, case report, combination treatment == 1. Introduction == Granulomatous polyangiitis (GPA) is usually characterized by necrotizing granulomatous polyangiitis involving the ear, nose, upper and lower airways. Necrotizing vasculitis primarily involves small and medium-sized vessels and can involve life-threatening organs, such as alveolar hemorrhage. Rapidly progressive glomerulonephritis which manifests pathologically as crescentic glomerulonephritis, carries a high risk of progression to end stage renal disease (ESRD) or dialysis-dependent risk (1). GPA is usually a form of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and usually manifests itself as either cytoplasmic ANCA-positive (C-ANCA) or anti-protease 3 (anti-PR3) antibody-positive (2,3). Histopathologically, infiltration of lymphocytes, plasma cells and multinucleated giant cells and necrotizing granulomatous inflammation of small and medium-sized blood vessels are mostly manifested in cells and tissues. Compared with normal people, naive B cells increased during AVV activity and GPA remission period (4,5), and naive B cells were more sensitive to BCR stimulation during GPA activity period (6). The decrease in memory B cells observed in some disease activities may be due to increased differentiation into plasma cells, which migrated to sites of inflammation instead of peripheral blood (5). Besides, it is reported a Tolrestat decrease in percentage of B1 like B cells during the active phase of vasculitis (7) and a recovery in the number of B cell during remission (8). B cells also secreted pro-inflammatory cytokines such as IL-6 and TNF, which can reduce the increase in anti-inflammatory activity of T cells (9).B-lymphocyte stimulator (BLyS, also known as B-cell activating factor, BAFF) and proliferation-inducing ligand (APRIL) are members of the tumor necrosis factor (TNF) family, which are key factors in the survival and maturation of B-lymphocytes, and have also been implicated in the pathogenesis of a wide range of human autoimmune disorders (10). It has been shown that even in antineutrophil cytoplasmic antibody-associated vasculitis (AAV) remission, elevated expression of TACI in CD19+ cells, immature B cells, and the proportion of plasmablast (PB)/plasma cell (PC) Tolrestat is accompanied by persistently high levels of BAFF and APRIL in serum (11). Persistent abnormalities in BAFF/APRIL signaling may lead to disease CD300C recurrence (12). Telitacicept is a novel fully human TACI-Fc recombinant fusion protein targeting B lymphocyte stimulators. It can block BLyS to inhibit the development and maturation of aberrant B cells and block APRIL to inhibit antibody production by aberrant plasma cells (11,1316). As we reported below, we observed favorable safety and efficacy of telitacicept in combination with conventional therapies (hormones, immunoglobulins, and CYC) for the treatment of patients with severe, rapidly progressive renal impairment who with pathological manifestations of crescentic nephritis with plasma cell infiltration. == 2. Case presentation == A 64-year-old man was admitted to the Seventh Affiliated Hospital of Sun Yat-sen University in June 2023 because of Tolrestat hearing loss for 3 months, cough for 2 months and creatinine increase for 2 weeks. The patient had been in his usual state of health until 3 months before admission, when hearing loss, symmetry in both ears, and yellow discharge from the external ear canal designed. One month later, the patient presented cough, a small amount of white sputum, low fever, headache, and.