RT Journal Article SR Electronic T1 Secondary haemophagocytic lymphohistiocytosis in hospitalised COVID-19 patients as indicated by a modified HScore is infrequent and high scores do not associate with increased mortality JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP clinmed.2021-0053 DO 10.7861/clinmed.2021-0053 A1 Michael R Ardern-Jones A1 Matt Stammers A1 Hang TT Phan A1 Florina Borca A1 Anastasia Koutalopoulou A1 Ying Teo A1 James Batchelor A1 Trevor Smith A1 Andrew S Duncombe YR 2021 UL http://www.rcpjournals.org/content/early/2021/08/13/clinmed.2021-0053.abstract AB A significant proportion of COVID-19 patients show evidence of hyperinflammation (HI), of which secondary haemophagocytic lymphohistiocytosis (sHLH) is the most severe manifestation and diagnosed with HScore. Using a COVID-relevant modification of the HScore (%HScore), we set out to determine the prevalence of sHLH in 567 COVID-19 inpatient cases.The overall incidence of individuals with an 80% probability of sHLH in our COVID-19 cohort was 1.59% on admission and only rose to 4.05% if calculated at any time during admission. This small cohort as defined by %HScore showed no excess mortality compared with the whole cohort. Overall, %HScores were lower in older patients (p < 0.0001) and did not reliably predict outcome at any cut-off value (AUROC 0.533, p=0.211, odds ratio 0.99).Our study demonstrates that a modified version (%HScore) of the conventional sHLH scoring system (HScore) does not enable risk stratification in people hospitalised with COVID. We propose further work is needed to develop novel approaches to predict HI and improve trial stratification for HI directed therapy in people with COVID-19.