Clinical values of morphology of hemophagocytes in infection associated hemophagocytic lymphohistiocytosis / 中华检验医学杂志

ABSTRACT

Objective:To study the morphology of hemophagocytosis (HPC) in bone marrow smears of patients with infection-associated hemophagocytic lymphohistiocytosis (IAHLH), and further analyse if there were differences in the clinical and laboratory features, the cytokines level and prognosisMethods:24 patients newly diagnosed with IAHLH from 2016-Dec-1 to 2021-Dec-31 in Beijing Friendship Hospital were included as study group, and 20 patients with infectious disease as non-HLH control group. In IAHLH group, mean age was 34±13 years, including 17(71%) males and7(29%) females. In Non-HLH group, mean agewas 43±16 years, including 14 (70%) males and6 (30%) females. Depending on re-checking phagocytic cell type on the initial bone marrow smear, the HPCs were divided into HPC-1, phagocytizing non-nucleated cells (mature erythrocyte or platelets), and HPC-2, phagocytizing nucleated cells. The differences in clinical presentations covered in HLH-2004 criteria, cytokines value(IL-6, IL-10, IL-18, IFN-γ) recommended in HLH-2022-China guideline, and the mortality within 1 year of diagnosis, were compared between IAHLH and non-HLH groups, between patients with or without HPC, and between patients with HPC-2 or only with HPC-1. For categorical variables, two groups were compared with the use of either the chi-square test or Fisher′s exact test. For non-normal distribution continuous variables, the difference between two groups variation was performed by using Mann-Whitney U test, and for normal distribution continuous variables, the difference was by the Independent Samples t-test.Results:The positive rates of fever, hepatomegaly and splenomegalyand the motrtality in IAHLH were 100% (24/24), 63% (15/24), 92% (22/24) and 46% (11/24), respectivelyin non-HLH were 55%(11/20),0(0/20),25% (5/20),0(0/20),and the differences between two groups were all statistically significant( P<0.01), but thedifferences between groups with and without HPC and between IAHLH patients with HPC-2 or only with HPC-1 were no statistically significanlly, ( P>0.05).In IAHLH group, IFN-γ in patients with HPC-2 was 400(246, 532)ng/L, significantly higher than 146(38, 180)ng/L in patients only with HPC-1 [ P=0.02, 95% CI was 233(75.8 to 397)], andthe other test parameters and cytokines level showed no obvious differences ( P>0.05).