The hemophagocytic lymphohistiocytic syndrome (HLH) has been reported in critically ill patients with confirmed sars-cov-2 infection and contributes to their morbidity and mortality. Precise criteria for diagnosis and monitoring of HLH in these patients are essential for improving their clinical outcomes. The diagnosis of HLH depends on several clinical, laboratory, and morphologic parameters according to the HLH-2004 guidelines and its update for adult patients. Recently, the H-score tool

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... des a quantitative score that can be used to monitor clinical severity and detect early cases with incomplete criteria. Other differential diagnoses which should be considered in COVID-19 infection associated with 2ry HLH are sepsis and septic shock, and cytokine release syndrome (CRS) due to a wide overlap of