Acute respiratory distress syndrome as an initial presentation of hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening multisystem disorder characterized by immune system dysregulation, hypercytokinemia, and hyperinflammation. This excessive inflammatory response is triggered by the uncontrolled activation of macrophages and T-lymphocytes, leading to widespread tissue damage. Systemic Lupus Erythematosus (SLE), a chronic autoimmune disease, involves the immune system’s loss of tolerance to nuclear self-antigens, resulting in the production of damaging autoantibodies that can affect multiple organ systems. In this case report, we describe a rare presentation of HLH in a young female patient with a known history of SLE. She initially presented with acute respiratory distress syndrome (ARDS), an uncommon but serious manifestation of HLH. The patient, who had discontinued her lupus medications two years prior, developed high-grade fever, generalized myalgia, and progressive respiratory distress, necessitating mechanical ventilation. Her condition rapidly deteriorated despite aggressive supportive measures, with laboratory investigations revealing pancytopenia, hyperferritinemia, and elevated inflammatory markers, ultimately leading to the diagnosis of HLH. This case highlights the diagnostic challenges and the importance of early recognition of HLH in patients with underlying autoimmune conditions, such as SLE, who present with severe systemic inflammation and respiratory failure. Timely intervention is crucial, as delay in diagnosis and treatment can result in fatal outcomes. The case underscores the need for heightened clinical suspicion of HLH in similar presentations, as well as a multidisciplinary approach to management to improve patient prognosis.