Abstract Background/Aims Haemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening hyperinflammatory syndrome. Patients usually present with fevers, pancytopenia, hepatosplenomegaly, liver and CNS dysfunction due to unchecked immune activation progressing to multi-organ failure. The GIRFT HLH pathway was introduced in 2024 to improve recognition and survival from this condition. We conducted a retrospective review describing the demographics, clinical features, laboratory characteristics, treatment, and outcomes of HLH cases in our centre. Methods A retrospective review of 45 patients diagnosed with HLH between 2010 and 2025 was conducted. Diagnosis was established using HLH-2004 criteria and HScore stratification (cut-off ≥169). Data regarding demographics, triggers, organ involvement, laboratory results, treatment, and survival outcomes were analyzed. The standard of care was reviewed against the GIRFT HLH pathway which was introduced in 2024. Results Out of 45 patients, 24 (53.3%) were female, with a mean age of 48.3 years (range 13-86 years). The majority were White British (60%), followed by Asian (22.2%), Black African (6.7%), and others. Only 1 patient (2.2%) had primary HLH, while 44 (97.8%) were classified as secondary HLH. Rheumatological disease was the most common trigger (42.2%), followed by infections (40%), malignancy (13.3%), and iatrogenic causes (4.4%). Based on HScore, 27 (60%) patients had scores above the diagnostic threshold of 169. Organ involvement was frequent, with 36 (80%) patients demonstrating liver dysfunction,12 (27%) splenomegaly, 9 (20%) skin manifestations, 4 (1%) CNS involvement, and 3 (1%) hepatomegaly. Cytopenias affected ≥2 lineages in 25 (55.6%) patients. Mean laboratory results showed CRP 140.1 mg/L, LDH 938.7 U/L, AST 199.6 U/L, and ALT 194.7 U/L. Hyperferritinaemia was a consistent finding, with mean ferritin of 8448.6 μg/L at presentation, peaking at 16,823.2 μg/L. Bone marrow aspiration was performed in 5 patients. Treatment given was variable and corticosteroids were most frequently used, with 35 patients receiving high-dose steroids. Immunomodulatory therapy included anakinra (12), ciclosporin (10), IVIG (6), tocilizumab (8), rituximab (3), etoposide (1), and disease-specific therapies such as MMF (3) and methotrexate (4). The overall survival was 66.7% (30/45). The mean length of hospital stay was 25.2 days. Eighteen patients (40%) required intensive care support. Most diagnoses of HLH (31 patients, 68.9%) occurred between 2020 and 2025, reflecting improved recognition and diagnostic practices in the last 5 years of the study. Conclusion In our cohort of patients, HLH was predominantly secondary and associated with autoimmune disease or infections. Corticosteroids remained the mainstay of therapy and increasingly supplemented with biologics such as anakinra. Despite treatment, death occurred in one-third of patients. Increased recognition of HLH in the last third of this study highlights increased awareness. These findings highlight the importance of early recognition and initiation of therapy with multidisciplinary input to improve survival. Disclosure S. Jain: None. H. Zafar: None. J. McNally: None. A. Chan: None.
Jain et al. (Wed,) studied this question.