Management of haemophagocytic lymphohistiocytosis: service evaluation of a national multi-disciplinary meeting

Abstract Background/Aims Haemophagocytic lymphohistiocytosis (HLH) is a devastating condition caused by uncontrolled activation of the immune system. If left untreated, the condition leads to multi-organ failure and death. Even with treatment, recent UK data has shown a mortality rate of 50%. In 2019, a group of clinicians from University College London Hospital (UCLH) came together with the aim of improving outcomes for patients with HLH. The UCLH HLH multi-disciplinary meeting (MDM) has been running since that time and includes representation from rheumatology, haematology, infectious diseases, tropical medicine, virology, neurology, and critical care. Clinicians from any UK trust are invited to join and present patients. As part of a service evaluation project, we aimed to assess the scope of this meeting with regards to the number, demographics and primary diagnoses of patients discussed and the geographical location of the referring clinical team. Methods This is a retrospective descriptive analysis of all patients discussed at the UCLH HLH MDT from 2nd September 2020 to 20th July 2022. Data were obtained from electronic health records and analysed in Prism version 9.4.1. This work has been registered as a service evaluation project within the Division of Medical Specialities at UCLH. Results 93 patients were discussed. 38 were female. 55 were male. The median age was 38 years. Triggers for HLH were haematological malignancy (38.0%), infection (29.3%) rheumatological (14.1%) primary HLH (6.5%) and unknown (7.6%). In 4 patients, HLH was not felt to be the underlying diagnosis. 40 patients were managed as inpatients at UCLH, 37 of whom were transferred from other trusts. Geographical data were obtained on 81 patients. Patients were referred from all 9 regions of England: London (34), North East (1), North West (2), Yorkshire (2), East Midlands (1), West Midlands (3) South East (11), East of England (11), South West (11) as well as Wales (2), Scotland (2) and Ireland (1). Haemophagocytosis was confirmed on bone marrow biopsy in 66.7% of patients. Mortality data showed that 32 (34%) patients died following their diagnosis. Conclusion A multi-disciplinary approach is essential in the management of HLH. Our data show that patients with HLH are young, have a high mortality and broad range of pathology. The UCLH HLH MDT currently serves a wide geographical area across the UK and UCLH acts as a tertiary referral centre for patients with the condition. Disclosure N.S. Shah: None. M. Hutchinson: None. S. Clark: None. E. Sanchez: None. M. Brown: None. N. Stone: None. A.S. Carr: None. B. Carpenter: None. A. Laurence: None. S.H. Gohil: None. R.S. Tattersall: None. J.J. Manson: None. A. Jones: None.