Successful Management of Severe Refractory ARDS in Hemophagocytic Lymphohistiocytosis with VV-ECMO: A Case Report and Analysis

BACKGROUND Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening systemic inflammatory disorder characterized by cytokine storm, coagulation abnormalities, and pancytopenia, which can rapidly progress to multi-organ failure. Although acute respiratory distress syndrome (ARDS) is a less common but severe complication of HLH, veno-venous extracorporeal membrane oxygenation (VV-ECMO) can serve as a lifesaving intervention in cases unresponsive to standard treatments. Emerging case reports indicate that, when appropriately indicated, VV-ECMO can offer substantial clinical benefits. CASE REPORT A 45-year-old woman presented with 1 week of high-grade fever, fatigue, anorexia, and progressive dyspnea. Initial workup showed thrombocytopenia (platelets 30×10⁹/L), elevated C-reactive protein, and bilateral ground-glass opacities on chest computed tomography. Despite lung-protective settings, her PaO₂/FiO₂ ratio stayed below 80 mmHg. VV-ECMO was started on day 2 in the Intensive Care Unit, promptly restoring SpO₂ and reducing vasopressor needs. Further evaluation met HLH-2004 criteria: hyperferritinemia, high soluble CD25, splenomegaly, bone marrow hemophagocytosis, and elevated EBV DNA. Under ECMO support, she received high-dose methylprednisolone (1 g/day×5 days), a prednisone taper, and etoposide on day 18. She was weaned from ECMO on day 8, extubated on day 20, and discharged on day 45, with normalized laboratory values. At the 4-year follow-up, she remained in complete remission. CONCLUSIONS Early VV-ECMO can be life-saving in adult patients with HLH-associated ARDS by providing a window for targeted immunosuppression and chemotherapy. Rapid HLH recognition, multidisciplinary management, and timely ECMO initiation are essential. Further studies should refine patient selection, timing, and integrated treatment protocols.