Sepsis as the Grand Mimic of Secondary Hemophagocytic Lymphohistiocytosis: Serratia marcescens Bacteremia with Concomitant Decompensated Cirrhotic Liver Disease

Secondary hemophagocytic lymphohistiocytosis (HLH) is an elusive entity with sequelae that may be confused with sepsis. We discuss a 45-year-old man with decompensated liver cirrhosis with sepsis treated with broad-spectrum intravenous antibiotics. Further work-up initially supported sepsis-HLH overlap syndrome (SHLHOS) and corticosteroids were added. Ongoing refractory hypotension ensued, and the patient passed within 31 hours of presentation. Based on the patient's overwhelming immune activation and clinical course likely unsalvageable by cytotoxic immunosuppressive agents, the patient was diagnosed with sepsis with acute end organ dysfunction. This case report illustrates both the diagnostic challenge of sepsis versus HLH, which both require very different treatments, and the potential for rapid clinical decline without swift recognition and management of the true pathology.