Lymphoma-associated Hemophagocytic Syndrome: Case Report of a Natural Killer

Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening clinical syndrome, caused by an unregulated activation of cytotoxic T cells and macrophages. In adult patients, it is generally triggered by an underlying disease, with a significant proportion of cases being associated with malignancies (mainly lymphoma). The triad of fever, cytopenias, and hepatosplenomegaly is usually present, but, in severe cases, most patients will have a syndrome resembling sepsis and multiple organ failure, requiring admission into a critical care unit. We present a case of a 33-year-old healthy male patient, who presented with fever, malaise, and lower gastrointestinal bleeding. Upon admission, he was hypotensive and had elevated inflammatory markers, pancytopenia, and liver damage. Due to worsening shock of presumed septic and hemorrhagic origin, he was admitted to our ICU. An extensive diagnostic work-up was performed, including a bone marrow aspirate that revealed active hemophagocytosis and pleural effusion analysis that revealed abundant NK-Cells, phenotypically compatible with aggressive NK-Cell lymphoma. Anti-inflammatory and neoplastic treatments were immediately initiated, with a partial and transient response. Nonetheless, he developed refractory shock and medullary aplasia and died twenty days after being admitted. Although it is uncommon in adults, HLH is an important sepsis differential diagnosis to be aware of because it necessitates specific and timely treatment. Further investigation to determine and treat the possible underlying causes, including occult malignancies, is of paramount importance.