Abstract: Objective　To examine the relationship between serum vitamin D level and immune imbalance in advanced schistosomiasis patients with liver fibrosis. Methods　A total of 120 advanced schistosomiasis patients with liver fibrosis that were admitted to the Department of Schistosomiasis of The First Hospital of Jiaxing City from May 2016 to September 2018 were recruited as the observation group, and 50 healthy volunteers randomly sampled from the hospital during the same period served as the control group. The serum IgG antibody, IgA antibody, C3 complement, C4 complement, CD4+ cell proportion, CD8+ cell proportion, 25?hydroxyvitamin D [25(OH)D] levels were compared between the two groups. Liver fibrosis was classified into grade I, II and III according to the classification criteria of liver fibrosis by ultrasonography, and the serum IgG antibody, IgA antibody, C3 complement, C4 complement, CD4+ proportion, CD8+ proportion, 25(OH)D levels were compared among patients with grade I, II and III liver fibrosis. In addition, all patients were classified into the sufficient group, the insufficient group and the deficient group according to the serum vitamin D level, and the serum IgG antibody, IgA antibody, C3 complement, C4 complement, CD4+ proportion, CD8+ proportion, 25(OH)D levels were compared among these three groups. Moreover, the associations of the serum vitamin D level with these immune indicators were examined. Results　The 120 advanced schistosomiasis patients with liver fibrosis included 58 men and 62 women, and had a mean age of (72.00 ± 3.00) years. There were 32 cases with grade I liver fibrosis, 46 cases with grade II liver fibrosis, and 42 cases with grade III liver fibrosis. There were no significant differences between the observation group and the control group in terms of serum D?dimer, total cholesterol (TC), triglyceride (TG), C3 complement or C4 complement levels (t = 2.467, 0.322, 0.790, -2.432 and -2.630, all P values > 0.05); however, there were significant differences seen in alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood calcium, blood phosphorus, IgG antibody, IgA antibody, CD4+ proportion, CD8+ proportion, and 25(OH)D levels (t = 5.130, 6.382, -1.341, 2.361, 8.708, 11.783, -2.995, -6.543 and -3.022, all P values < 0.05). In addition, there were significant differences in AST, ALT, blood phosphorus, IgA antibody, C3 complement, CD8+ cell proportion and 25(OH)D levels among patients with grades I, II and III liver fibrosis (F = 19.704, 16.254, 62.669, 49.347, 5.430, 5.434 and 5.783, all P values < 0.05). There were significant differences in ALT, blood phosphorus, IgA antibody, CD8+ cell proportion and 25(OH)D levels between patients with grades I and III liver fibrosis (all P values < 0.05), and significant differences were seen between patients with grades II and III liver fibrosis in terms of blood phosphorus, IgA antibody and CD8+ cell proportion (all P values < 0.05), while there was a significant difference in the CD8+ cell proportion between patients with grades I and II liver fibrosis (P < 0.05). Moreover, there were significant differences among the sufficient, insufficient and deficient groups in terms of IgG antibody, IgA antibody, C3 complement, CD4+ cell proportion and CD8+ cell proportion (F = 13.303, 59.623, 8.698, 9.969 and 12.805, all P values < 0.05), and there was a significant difference in the CD8+ cell proportion between the insufficient and deficient groups (P < 0.05). Pearson correlation analysis revealed that serum 25(OH)D level were negatively associated with IgG and IgA antibody levels (r = -0.754 and -0.773, both P values < 0.05), and positively associated with C3 complement, CD4+ cell proportion and CD8+ cell proportion in advanced schistosomiasis patients with liver fibrosis (r = 0.827, 0.850 and 0.830, all P values < 0.05). Conclusions　Immune imbalance occurs in advanced schistosomiasis patients with liver fibrosis, and serum vitamin D level may correlate with immune imbalance in advanced schistosomiasis patients with liver fibrosis.

Key words: Advanced schistosomiasis, Liver fibrosis, Vitamin D, Immune imbalance

摘要： 目的　探索晚期血吸虫病肝纤维化患者血清维生素D水平与免疫失衡间的关系。方法　选择2016年5月至2018年9月就诊于嘉兴市第一医院血吸虫病科的120例晚期血吸虫病肝纤维化患者作为观察组，选取50例同期该院健康体检者作为对照组，比较两组血清中IgG抗体、IgA抗体、C3补体、C4补体、CD4+细胞比例、CD8+细胞比例、25羟维生素D [25（OH）D]等指标水平。根据超声肝纤维化分级标准，将患者分为肝纤维化I、II、III级，比较不同程度肝纤维化患者血清中上述指标水平差异。根据患者血清中维生素D水平，将患者分为25（OH）D水平充足组、不足组和缺乏组，比较各组患者上述指标水平差异，并分析维生素D水平与免疫指标间的相关性。结果　120例晚期血吸虫病肝纤维化患者中，男性58例、女性62例，平均年龄（72.00 ± 3.00）岁；肝纤维化I级32例、II级46例、III级42例。观察组和对照组血清D?二聚体（D?D）、总胆固醇（TC）、甘油三酯（TG）、C3补体、C4补体水平差异均无统计学意义（t = 2.467、0.322、0.790、?2.432、?2.630，P均 > 0.05），但天门冬氨酸氨基转移酶（AST）、丙氨酸氨基转氨酶（ALT）、血钙、血磷、IgG抗体、IgA抗体、CD4+细胞比例、CD8+细胞比例、25（OH）D水平差异均有统计学意义（t = 5.130、6.382、?1.341、2.361、8.708、11.783、?2.995、?6.543、?3.022，P均 < 0.05）。不同肝纤维化程度患者AST、ALT、血磷、IgA抗体、C3补体、CD8+细胞比例、25（OH）D水平差异均有统计学意义（F = 19.704、16.254、62.669、49.347、5.430、5.434、5.783，P均 < 0.05）；肝纤维化I级与III级患者ALT、血磷、IgA抗体、CD8+细胞比例、25（OH）D水平差异均有统计学意义（P均 < 0.05），肝纤维化II级与III级患者血磷、IgA抗体、CD8+细胞比例差异均有统计学意义（P均 < 0.05），肝纤维化I级与II级患者CD8+细胞比例差异有统计学意义（P < 0.05）。25（OH）D水平充足组、不足组与缺乏组患者血清IgG抗体、IgA抗体、C3补体、CD4+细胞比例、CD8+细胞比例差异均有统计学意义（F = 13.303、59.623、8.698、9.969、12.805，P均 < 0.05），不足组与缺乏组患者血清CD8+细胞比例差异有统计学意义（P < 0.05）。Pearson相关性分析显示，晚期血吸虫病肝纤维化患者血清25（OH）D水平与IgG抗体、IgA抗体水平呈负相关（r = ?0.754、?0.773，P均 < 0.05），与C3补体、CD4+细胞比例、CD8+细胞比例呈正相关（r = 0.827、0.850、0.830，P 均 < 0.05）。结论　晚期血吸虫病肝纤维化患者存在免疫失衡，患者血清中维生素D水平可能与免疫失衡有关。

关键词: 晚期血吸虫病, 肝纤维化, 维生素D, 免疫失衡