Case Report: A "visceral vasculitis storm" in Systemic Lupus Erythematosus: simultaneous enteritis, ureteritis, and splenic infarction in a pediatric patient.

Background: Systemic Lupus Erythematosus (SLE) is a multi-system autoimmune disease. Although lupus enteritis is a recognized manifestation of mesenteric vasculitis, lupus ureteritis is rare. The simultaneous occurrence of both, termed a "visceral vasculitis storm," poses a significant diagnostic challenge. Clinicians often struggle to differentiate primary ureteritis from secondary mechanical compression caused by intestinal edema (the "monistic" view). Case presentation: A 16-year-old girl with a history of transient ptosis and positive ANA/dsDNA results 4 months prior to the current presentation, presented with abdominal pain, fever, and transient dysuria. Initial outpatient CT revealed bilateral hydroureteronephrosis. During hospitalization, the patient's condition deteriorated despite antibiotic therapy. A repeat contrast-enhanced CT (CECT) demonstrated the classic "target sign" in the bowel wall, splenic infarction, and crucially, distinct ureteral wall enhancement. Laboratory findings showed a "high CRP/low PCT" dissociation and a markedly elevated D-Dimer (13.74 μg/mL). The diagnosis was revised to SLE with diffuse visceral vasculitis. The patient responded rapidly to methylprednisolone pulse therapy and IVIG, followed by maintenance therapy with Cyclophosphamide and the dual BLyS/APRIL inhibitor Telitacicept. Conclusion: This case highlights that ureteral wall enhancement on CECT can serve as a potentially useful radiologic clue for primary lupus ureteritis. Recognizing the "visceral vasculitis storm" is essential to avoid the pitfalls of diagnostic monism and to initiate aggressive immunosuppressive therapy promptly to prevent irreversible organ damage.