(1153) Unmasking Lupus: The Pulmonary-Renal Surprise

Introduction: Pulmonary-renal syndrome (PRS) is a severe condition characterized by simultaneous Diffuse Alveolar Hemorrhage (DAH) and rapidly progressive glomerulonephritis. Though this syndrome is strongly associated with ANCA-associated vasculitis and anti-GBM disease, it can also be seen in other autoimmune disorders. We describe a rare case of PRS as the initial presentation of systemic lupus erythematosus (SLE), highlighting the need for prompt and aggressive management.

Description: An 18-year-old female with no known medical history presented with dyspnea and hemoptysis. CT chest showed bilateral, centrally located, consolidations with associated ground glass opacities, suggesting DAH. Bronchoscopy confirmed DAH with progressively bloodier bronchial alveolar lavage samples. The clinical picture was further complicated by acute kidney injury and worsening hypoxemia. She quickly progressed to requiring mechanical ventilation for severe ARDS. This was managed with low tidal volume ventilation, proning, and epoprostenol. Renal function progressively worsened to anuric renal failure. Therefore, treatment for PRS was initiated with plasmapheresis and pulse-dose steroids. Her renal dysfunction progressed, necessitating continuous renal replacement therapy. Serology returned positive for ANA and other antibodies consistent with SLE and low complement levels. Antibodies for MPO, PR3, and anti-GBM were negative. She was given a dose of cyclophosphamide and steroid taper was initiated. Renal biopsy showed class IV lupus nephritis. Post-extubation, she was gradually weaned off CRRT and oxygen support, and transferred out of the critical care unit on steroid taper and hydroxychloroquine.

Discussion: This case points to the critical nature of PRS, necessitating immediate stabilization and aggressive management. Importantly, it demonstrates that even without an underlying diagnosis, initiating treatment for suspected autoimmune pathology can be life-saving and effective, highlighting a successful approach to managing ANCA-negative PRS. PRS is an uncommon presentation of lupus highlighting the need for aggressive management and broad diagnostic workup.