Objective: To investigate the association between genotype and clinical phenotype in children with primary hemophagocytic lymphohistiocytosis (HLH). Methods: Clinical data of 38 children with primary HLH at Beijing Children's Hospital from November 2015 to October 2020 were analyzed retrospectively. According to whether destructive mutation site, familial HLH (FHL) or non-familial HLH, degranulation pathway and non-degranulation pathway were detected in them, these patients were divided into different groups. Clinical characteristics, laboratory tests and functional tests were analyzed in different groups. Wilcoxon test or chi-square test were used for comparison between groups. Results: Among 38 cases, there were 23 males and 15 females. The age of onset was 2.5 (0.1-13.7) years. PRF1 (13/38, 34%) and UNC13D (12/38, 32%) gene mutations had the highest detectable rate. Correlation analysis between genotypes and phenotypes suggested that patients in destructive mutation sites group (n=25) had a younger age of onset than that in non-destructive mutation sites group (n=13) (1.0 (0.1-9.0) vs. 4.0 (0.4-13.4) years, Z=-2.711, P=0.005). The incidence of central nervous system involvement and convulsion was higher in patients in familial HLH group (n=26) than that in non-familial HLH group (n=12)(62% (16/26) vs. 2/12, χ²=6.631, P=0.015; 54% (14/26) vs. 2/12, χ²=4.656, P=0.040). The levels of soluble CD25, bilirubin, interferon γ (IFN-γ) and interleukin 10 (IL-10) were higher in degranulation pathway impairment group than that in the non-degranulation pathway impairment group (38 444 (2 393-44 000) vs.15 304 (1 620-36 937) ng/L,Z=2.634,P=0.008; 23.5 (6.3-126.4) vs. 6.0 (3.6-31.0) μmol/L, Z=2.992, P=0.003; 20.7 (0-248.7) vs. 11.9 (2.6-21.0) ng/L, Z=2.156, P=0.031; 20.7 (4.3-2 500.0) vs. 11.8 (4.0-88.0) ng/L, Z=2.210, P=0.027). However, the levels of neutrophils, ferritin and lactate dehydrogenase (LDH) in degranulation pathway impairment group were lower in the non-degranulation pathway impairment group (0.5 (0.1-8.0)×109 vs. 1.0 (0.9-2.3)×109/L, Z=-3.197, P=0.001; 1 133 (78-10 452) vs. 3 048 (630-37 900) μg/L, Z=-2.407, P=0.016; 410 (188-1 254) vs. 599 (389-3 147) U/L, Z=-2.489, P=0.013). Conclusions: PRF1 and UNC13D gene mutations are most common in primary HLH. Patients with destructive gene mutations have a younger age of onset. Patients with familial HLH are more likely to have central nervous system involvement and convulsions. The levels of sCD25, bilirubin, IFN-γ and IL-10 are higher in the degranulation pathway patients.
目的： 探讨原发性噬血细胞性淋巴组织细胞增生症（HLH）患儿基因型与临床特征的相关性。 方法： 回顾性研究。选择2015年11月至2020年10月就诊于北京儿童医院的38例原发性HLH患儿为研究对象，分别将患儿分为破坏性突变组和非破坏性突变组，家族性HLH（FHL）组和非FHL组，细胞脱颗粒功能受损组和非脱颗粒功能受损组，分析不同组间患儿的临床特点及实验室、功能学检查结果的差异。组间比较采用秩和检验或χ²检验。 结果： 38例患儿男23例、女15例，发病年龄2.5（0.1~13.7）岁。PRF1（13例，34%）和UNC13D（12例，32%）基因突变检出率最高。基因型与临床表型关联性分析结果提示，携带破坏性基因突变的患儿（25例）发病年龄小于非破坏性突变组患儿（13例）［1.0（0.1~9.0）比4.0（0.4~13.4）岁，Z=-2.711，P=0.007］。家族性HLH患儿（26例）的中枢神经系统受累和抽搐发生率高于非家族性HLH患儿（12例）［62%（16/26）比2/12，χ²=6.631，P=0.015；54%（14/26） 比 2/12，χ²=4.656，P=0.040］。脱颗粒通路受损组患儿（29例）可溶性CD25（sCD25）［38 444（2 393~44 000）比15 304（1 620~36 937）ng/L，Z=2.634，P= 0.008）、胆红素［23.5（6.3~126.4）比6.0（3.6~31.0）μmol/L，Z=2.992，P=0.003）、干扰素γ（IFN-γ）［20.7（0~248.7）比 11.9（2.6~21.0） ng/L，Z=2.156，P=0.031］、白细胞介素10（IL-10）［20.7（4.3~2 500.0）比11.8（4.0~88.0） ng/L，Z=2.210，P= 0.027］均高于非脱颗粒通路受损组患儿（9例），而中性粒细胞计数［0.5（0.1~8.0）×109 比 1.0（0.9~2.3）×109/L，Z=-3.197，P=0.001］、铁蛋白［1 133（78~10 452）比 3 048（630~37 900）μg/L，Z=-2.407，P=0.016］、乳酸脱氢酶［410（188~1 254）比599（389~3 147）U/L，Z=-2.489，P=0.013］明显低于非脱颗粒通路受损组。 结论： 在原发性HLH患儿中PRF1和UNC13D基因突变最常见。携带破坏性基因突变的患儿发病年龄较早；家族性HLH患儿更易出现中枢神经系统受累及抽搐；脱颗粒通路受损患儿sCD25、胆红素及IFN-γ、IL-10水平较高。.