Hemophagocytic lymphohystiocytosis (HLH) represents a severe hyperinflammatory condition with the cardinal symptoms prolonged fever, hepatosplenomegaly, and cytopenias. The most prominent histopathological feature of HLH is an accumulation of activated T lymphocytes and macrophages predominantly in lymphoid tissues. Although it can occur in all age groups, neonatal-onset HLH is very rare. We report on a case of HLH presenting with anemia and respiratory distress at birth. Several weeks prior to diagnosis the symptoms were attributed to a systemic infection. The child developed typical clinical and laboratory findings, and was diagnosed with HLH according to HLH-2004 guidelines. Chemo- -immunotherapy was initiated, but after a temporary control of the disease the patient succumbed to rapidly progressive HLH. Post-mortem, extensive hemophagocytosis was found in multiple organs. No specific genetic defect was identified. HLH is potentially fatal childhood disease. It is important for pediatricians to be able to early identify this disorder and commence the therapy before overwhelming disease activity develops
