血清淀粉样蛋白评价幼年特发性关节炎活动度的价值

Serum amyloid A in evaluating the activity of juvenile idiopathic arthritis

目的探讨血清淀粉样蛋白(SAA)水平的变化对幼年特发性关节炎(JIA)疾病活动度评估的价值。方法选取2017年1月至2018年3月在平湖市第一人民医院就诊的JIA患儿100例,检测患儿血清中C反应蛋白(CRP)、血沉(ESR)和SAA的水平及骨密度,采用幼年关节炎疾病活动评分-27量表(JADAS-27)评价JIA活动度。同时选取50例健康儿童作为对照组。分析JIA患儿血清SAA水平的变化及其与CRP、ESR的相关性。结果活动期JIA患儿SAA为(88.32±21.01)mg/L,明显高于健康儿童(16.54±6.87)mg/L,差异有统计学意义(t=25.809,P<0.05)。100例JIA患儿SAA与CRP、ESR呈正相关(r=0.801,P=0.031;r=0.710,P=0.022)。50例全身型JIA患儿SAA与CRP、ESR也呈正相关(r=0.881,P=0.002;r=0.770,P=0.008)。SAA与活动性关节炎个数和关节症状严重程度均无相关性(均P>0.05)。活动期患儿SAA(t=21.344)、CRP(t=7.643)、ESR(t=15.622)、白细胞(t=14.682)和血小板(t=7.910)水平均较稳定期患儿高,但骨密度(t=13.697)较稳定期患儿低,差异均有统计学意义(均P<0.05)。全身型JIA患儿SAA(t=18.911)、CRP(t=7.048)、ESR(t=7.841)和白细胞(t=22.689)水平均明显高于非全身型JIA患儿,差异均有统计学意义(均P<0.05),而血小板水平(t=0.075)和骨密度(t=0.937)的比较差异均无统计学意义(均P<0.05)。对于单项指标预测JIA活动度而言,SAA的诊断价值仅次于ESR。SAA联合血小板、CRP的曲线下面积分别为0.868和0.954,均大于0.7。活动期JIA患儿JADAS-27量表分数均高于稳定期患儿,差异均有统计学意义(均P<0.05)。相关性分析发现,JADAS-27总分与SAA、CRP、ESR、白细胞、血小板、骨密度有关(r值分别为0.451、0.501、0.608、0.401、0.311、-0.387,均P<0.05)。结论 SAA在全身型和活动期JIA患儿血清中明显增高,其与CRP和ESR这两种传统的JIA活动性评价指标相关性较佳,且与JADAS-27量表评分呈正相关。SAA联合血小板可能成为评价JIA疾病活动性的指标。

Objective To investigate the value of serum amyloid A(SAA) level in evaluating the disease activity of juvenile idiopathic arthritis(JIA). Methods One hundred children with JIA in First People’s Hospital of Pinghu from January 2017 to March 2018 were included in this study. The serum levels of C-reactive protein(CRP), erythrocyte sedimentation rate(ESR) and SAA as well as bone mineral density were measured. The juvenile arthritis disease activity score with 27-joint reduced count(JADAS-27) was used to evaluate the activity of JIA. Fifty healthy children were selected as control group. The correlation of SAA change in JIA cases with CRP and ESR was analyzed. Results SAA in active JIA children was 88.32±21.01 mg/L, which was significantly higher than that in healthy children(16.54±6.87 mg/L), and the difference was statistically significant(t=25.809, P<0.05). In 100 cases of JIA, SAA was positively correlated with CRP and ESR(r=0.801,P=0.031;r=0.710, P=0.022). In 50 cases of systemic JIA, SAA was also positively correlated with CRP and ESR(r=0.881,P=0.002;r=0.770,P=0.008). SAA was not related to the number of active arthritis and the severity of joint symptoms(both P>0.05). The levels of SAA(t=21.344), CRP(t=7.643), ESR(t=15.622), white blood cells(t=14.682) and platelets(t=7.910) in children at active stage were higher than those at stable period, but the bone mineral density was lower with significant differences(all P<0.05). The levels of SAA(t=18.911), CRP(t=7.048), ESR(t=7.841) and white blood cells(t=22.689) in children with systemic JIA were significantly higher than those in cases of non systemic JIA(all P<0.05), but there were no statistical differences in level of platelet(t=0.075) and bone mineral density(t=0.937)(both P<0.05). In predicting JIA activity with a single indicator, the diagnostic value of SAA was only inferior to ESR. The area under the curve of SAA combined with platelets and CRP was 0.868 and 0.954, which were greater than 0.7. The scores of JADAS-27 in children with active JIA were all higher than those in children at stable stage, and the differences were statistically significant(all P<0.05). The correlation analysis showed that the total score of JADAS-27 was related to SAA, CRP, ESR, white blood cells, platelets, and bone mineral density(r value was 0.451, 0.501, 0.608, 0.401, 0.311 and-0.387, respectively, all P<0.05). Conclusion SAA significantly increases in the serum of children with systemic and active JIA, which has a good correlation with two traditional JIA activity indexes of CRP and ESR and is positively correlated with the JADAS-27 score. SAA combined with platelets may become an indicator of JIA disease activity.