AQP4和IL-6诊断视神经脊髓炎和预后评估的价值

Diagnostic value of aquaporin 4 antibody and leukocyte mediator-6 in optic neuromyelitis and evaluation of prognosis

目的探讨水通道蛋白4抗体(AQP4)和白细胞介-6(IL-6)诊断视神经脊髓炎(NMO)和预后评估的价值。方法选取NMO及其谱系疾病患者57例为观察组,以及同期就诊的无神经系统损害的30例紧张性头痛患者为对照组。采用间接免疫荧光法检测血清AQP4,采用化学发光免疫法检测血清IL-6。结果(1)NMO及其谱系疾病患者57例,其中NMO 24例,长节段脊髓炎(LETM)13例,复发性脊髓炎(rLETM)4例,双眼视神经炎(BON)13例,复发性视神经炎(RION)3例。(2)观察组AQP4阳性率52.6%,对照组均为阴性,差异有统计学意义(P<0.05);观察组血清IL-6水平高于对照组,差异有统计学意义(P<0.05)。(3)NMO患者AQP4阳性率最高(83.3%),rLETM、RION、LETM和BON患者依次为75.0%、66.7%、30.8%和7.7%;NMO、rLETM和RION患者血清IL-6水平差异无统计学意义(P>0.05),但是均大于LETM和BON患者,差异有统计学意义(P<0.05);AQP4阳性率与IL-6水平呈正相关关系(r=0.651,P<0.05)。(4)以AQP4抗体滴度>20倍为界值,诊断NMO的灵敏度、特异度分别为89.3%、83.6%,曲线下面积(AUC)为0.902;以IL-6(73.5 pg/mL)为临界值,诊断NMO的灵敏度、特异度、AUC分别为70.3%、63.6%、0.695。(5)AQP4阳性NMO患者确诊为NMO的中位时间小于AQP4阴性患者,差异有统计学意义(P<0.05);85.0%的AQP4阳性NMO患者在初次发病24个月后确诊为NMO,大于AQP4阴性患者(25.0%),差异有统计学意义(P<0.05);随访中AQP4阳性患者3例BON复发,5例rLETM复发,AQP4阴性患者无复发,差异有统计学意义(P<0.05)。结论NMO及其谱系疾病患者AQP4和IL-6与对照组存在明显差异,尤其是AQP4对于NMO的诊断和预后评估有较高的临床价值。

Objective To investigate the diagnosis and prognostic evaluation of aquaporin 4 antibody(AQP4)and leukocyte mediator-6(IL-6)in neuromyelitis optica(NMO).Methods Fifty-seven patients with NMO and lineage diseases were selected as observation group,and 30 patients with tension headache without nervous system damage were selected as control group.Serum AQP4 was detected by indirect immunofluorescence assay and serum interleukin-6(IL-6)was detected by chemiluminescence immunoassay.Results(1)57 patients with NMO and lineage diseases,including 24 cases of NMO,13 cases of long segment myelitis(LETM),4 cases of recurrent myelitis(rLETM),13 cases of binocular optic neuritis(BON),and 3 cases of recurrent optic neuritis(RION).(2)The positive rate of AQP4 in the observation group was 52.6%,while that in the control group was negative,the difference is statistically significant(P<0.05);the level of serum IL-6 in the observation group was higher than that in the control group,the difference is statistically significant(P<0.05).(3)The highest positive rate of AQP4 was found in patients with NMO(83.3%),the positive rates of rLETM,RION,LETM and BON were 75.0%,66.7%,30.8%and 7.7%respectively.There was no significant difference in serum IL-6 levels between patients with NMO,rLETM and RION(P>0.05),but they were higher than those of patients with LETM and BON(P<0.05).The positive rate of AQP4 was positively correlated with the level of IL-6(r=0.651,P<0.05).(4)The sensitivity,specificity and area under curve(AUC)were 89.3%,83.6%,0.902 and 70.3%,63.6%and 0.695,respectively,when the titer of AQP4 antibody was more than 20 times as the threshold value.The sensitivity,specificity and AUC of diagnosis of NMO were 70.3%,63.6%and 0.695 respectively with IL-6(73.5 pg/mL)as the threshold value.(5)The median time of AQP4 positive NMO patients diagnosed as NMO was less than that of AQP4 negative patients(P<0.05);85.0%of AQP4 positive NMO patients diagnosed as NMO 24 months after the initial onset,which was higher than that of AQP4 negative patients(25.0%)(P<0.05);during follow-up,3 patients(15.0%)with BON recurrence,5 patients(25.0%)with rLETM recurrence and no recurrence in AQP4 negative patients(P<0.05),the difference was significant(P<0.05).Conclusion AQP4 and IL-6 in patients with NMO and its lineage diseases are significantly different from those in the control group,especially AQP4 has high clinical value in the diagnosis and prognosis evaluation of NMO.