Average temperature as a marker of lymphoma-associated HLH.

METHODS:This retrospective analysis aimed to assess whether a 12-hour mean temperature (measured around either diagnosis of HLH or peak ferritin value) has value as a quick and simple diagnostic test for HLH in people with lymphoproliferative disease (LPD). Hospital records from 2018 to 2022 were retrospectively screened for patients with LPD and peak ferritin during admission to hospital >3000ng/mL. Patients were grouped as either HLH or non-HLH after consensus discussion at a multi-disciplinary meeting with access to full, detailed patient records and H-scores. RESULTS:The total cohort of 23 patients consisted of 12 with HLH and 11 grouped as non-HLH. 12-hour mean temperature at HLH diagnosis was 38.6 °C in the HLH cohort and 37.5 °C measured at the point of peak ferritin measurement in non-HLH groups. It was also positively correlated with HLH status (P = 0.001) and showed high retrospective sensitivity and specificity for HLH above 37.7 °C. CONCLUSION:These results demonstrate that a 12-hour mean temperature may add value and diagnostic certainty to the first-line investigations for HLH associated with LPD. The moderately high sensitivity and specificity achieved with this dataset supports the need for further research into whether the test retains validity in larger patient groups.