A Rare Case of VEXAS (Vacuoles, E1 Enzyme, X-Linked, Autoinflammatory, Somatic)-Relapsing Polychondritis (RP) Syndrome with AKI

Introduction: VEXAS syndrome is a newly recognized disease entity featured by somatic mutation of UBA1 gene. Patients present with adult-onset inflammatory status, hematological abnormalities, while renal injuries are not commonly seen. Here we report a case of VEXAS syndrome, with recurrent fever, refractory anemia, relapsing polychondritis (RP) and AKI. Case Description: A 62-year-old male presented with recurrent high fever and moderate anemia; he had a past medical history of hypertension and diabetes. No improvement was seen after antibiotic treatments and iron supplements; his HGB fell to 58 g/L, followed by polyarthralgia and cauliflower ear manifestations, and AKI (SCr 76 to 403μmol/L with negative urine test). Further laboratory tests showed significant elevation of hsCRP, ESR, as well as ferritin. ECT scan showed inflammatory lesions of multiple joints. Bone marrow smear showed vacuoles in myeloid precursor cells (Figure 1), and the genetic test revealed UBA1 mutations. Kidney biopsy showed TIN with lymphocytes and monocytes infiltration(Figure 2). The patient was diagnosed with VEXAS-RP-TIN, and received glucocorticoids and cyclophosphamide. Roxadustat was prescribed for anemia. His fever and polyarthralgia ameliorated, HGB increased to 130 g/L, and SCr decreased to 99 μmol/L after three-month follow-up. During follow-up, the patient experienced mild Pneumocystis carinii infection, and received sulfamethoxazole for long-term prophylaxis. Discussion: For AKI patients with fever, hyper-inflammatory status, and refractory hematological abnormalities, bone marrow studies and gene tests should be employed to estimate VEXAS syndrome.Bone marrow smear showed vacuoles in myeloid precursor cellsKidney biopsy showed infiltration of lymphocytes and monocytes in renal interstitium（HE stain, ×200）