Procalcitonin for discrimination between activity of systemic autoimmune disease and systemic bacterial infection

Objective To investigate whether serum procalcitonin (PCT) levels could be useful to differentiate between systemic infection and the activity of the underlying disease in autoimmune disease. Methods In 18 patients with systemic lupus erythematodes (SLE) and 35 patients with systemic antineutrophil cytoplasmic antibody-associated vasculitis (AAV) clinical disease activity was assessed by score systems. Infection was defined by clinical and microbiological means. PCT was determined in parallel with concentrations of neopterin, interleukin-6 (IL-6), and C-reactive protein (CRP) in 397 serum samples. Results Only in 3 of the 324 samples taken from patients with autoimmune disease but without concomitant infection, serum PCT levels were above the normal range (>0.5 ng/ml), whereas neopterin, CRP and IL-6 were elevated in patients with active underlying disease. All systemic infections (N=16 in AAV-patients) were associated with markedly elevated PCT-levels (mean±SD:1.93±1.19 ng/ml). Conclusion PCT may serve as a useful marker for the detection of systemic bacterial infection in patients with autoimmune disease.     

Procalcitonin measurement for detection of serious bacterial infection in febrile children: comparison between two automated immunoassays

ObjectivesTo assess the concordance of procalcitonin values at 3 cut-off ranges in a cohort of pediatric samples presenting with fever without source, using two different automated immunoassays.Design and methods65 frozen samples from children presenting with fever without source were thawed, tested on both Kryptor and VIDAS systems, and compared using a regression analysis, a Bland–Altman difference plot, and analysis of concordance at the clinically relevant cut-off points.ResultsKryptor and VIDAS PCT results correlated remarkably well (r = 0.952), with no significant difference in the frequency distribution over the 3 cut-off ranges (p = 0.1384). The strength of the agreement was good (κ = 0.759) with an overall concordance of 84.6%.ConclusionCorrelation and concordance of PCT values measured by both systems were good. This finding allows clinical implementation of both techniques with the same nominal PCT cut-off values for detection of serious bacterial infection in children presenting with fever without source.     

外周血降钙素原在细菌感染与病毒感染中诊断阈值的初探

目的 探讨不同病因发热患者血清降钙素原（PCT）的诊断截断值（cut-off value）.方法 回顾性分析2006年4月至2012年10月以“发热待查”收治,年龄16岁以上,检测PCT前2d内未用过抗生素且最终病因明确的细菌或病毒感染住院病例,应用法国生物梅里埃公司miniVIDAS免疫分析仪及配套试剂采用酶联荧光分析技术检测患者血清PCT水平,应用ROC曲线判断细菌感染和病毒感染患者PCT水平的最佳cut-off值.结果 符合入选标准共150例,其中病毒感染性发热104例和细菌感染性发热46例;对细菌感染性发热和病毒感染性发热患者确立的PCT最佳cut-off值为0.5750 ng/ml,AUC为0.844,其敏感性、特异性、阳性预测值、阴性预测值和总预测准确率分别为67.4％、97.1％、85.71％、87.07％和79.33％;对全身性细菌感染与局部细菌感染患者确立的PCT最佳cut-off值为2.1450 ng/ml,其AUC为0.739,其敏感性、特异性、阳性预测值、阴性预测值和总预测准确率分别为76.9％、69.7％、50％、88.46％和71.74％.结论 血清PCT检测对诊断细菌感染性发热及全身性细菌感染具有较好诊断价值,分别以0.5750 ng/ml及2.1450 ng/ml作为cut-off值具有较好的敏感性和特异性,可提高发热患者的鉴别诊断效率.     

IgG型抗内皮细胞抗体与狼疮疾病活动性的相关性

目的:探讨IgG型抗内皮细胞抗体(IgG-AECA)及其滴度与系统性红斑狼疮(SLE)活动性间的相关关系。方法:将64例SLE患者分为SLE活动期组和SLE缓解期组,健康对照组为健康献血员。用间接免疫荧光法检测上述3组血清IgG-AECA的阳性率及滴度。以SLE疾病活动性评分(SLEDAI)为标准来统计SLE活动期组各患者的疾病活动性评分。结果:IgG-AECA的阳性率在SLE活动期组、SLE缓解期组及健康对照组中分别为53.8%、24.0%、0,3组的阳性率差异有显著性(P﹤0.05)。在SLE活动期组、SLE缓解期组IgG-AECA的滴度水平差异亦有显著性(P﹤0.05),SLE活动期组高于SLE缓解期组。SLE活动期组的IgG-AECA滴度与SLEDAI之间存在正相关性。结论:SLE患者血清IgG-AECA及滴度水平可能在SLE的病情活动中起着重要作用。IgG-AECA的滴度水平在经治疗后的缓解期患者低于SLE活动期患者,可作为评估治疗效果及判断疾病活动性的指标之一。     

Procalcitonin as a marker of bacterial infection in the emergency department: an observational study

Introduction  

Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients; its level is related to the severity of infection. We evaluated the value of PCT as a marker of bacterial infection for emergency department patients.     

Understanding valvular heart disease in patients with systemic autoimmune diseases

Specific systemic autoimmune diseases are associated with distict valvular heart disorders. We discuss the valvular disorders associated with rheumatoid arthritis, systemic lupus erythematosus, antiphospholipid antibody syndrome, the seronegative spondyloarthropathies, the systemic vasculitides, and scleroderma.     

系统性红斑狼疮伴自身免疫性甲状腺病的临床分析

目的探讨系统性红斑狼疮(systemic lupus erythematosus,SLE)伴发自身免疫性甲状腺病(autoimmune thyroid-ism disease,AITD)和甲状腺抗体的情况。方法采用放射免疫分析法测定100例SLE患者中甲状腺激素水平及血清甲状腺微粒体抗体(TMAb)和甲状腺球蛋白抗体(TGAb)水平。结果 100例SLE患者有9例(9%)伴发AITD,其中甲状腺功能减退6例,甲状腺功能亢进2例,亚急性甲状腺炎1例;伴发AITD的SLE患者出现甲状腺抗体的阳性率高于未伴发AITD的患者(P=0.000),合并甲状腺功能减退患者TMAb阳性率高于TGAb阳性率。结论 SLE患者甲状腺功能减退的发生率为6%,AITD发生率远高于普通人群0.4%,SLE伴发AITD并不少见,应重视甲状腺功能和甲状腺抗体的检测。     

Role of IL-17 and regulatory T lymphocytes in a systemic autoimmune disease

To explore the interactions between regulatory T cells and pathogenic effector cytokines, we have developed a model of a T cell-mediated systemic autoimmune disorder resembling graft-versus-host disease. The cytokine responsible for tissue inflammation in this disorder is interleukin (IL)-17, whereas interferon (IFN)-gamma produced by Th1 cells has a protective effect in this setting. Because of the interest in potential therapeutic approaches utilizing transfer of regulatory T cells and inhibition of the IL-2 pathway, we have explored the roles of these in the systemic disease. We demonstrate that the production of IL-17 and tissue infiltration by IL-17-producing cells occur and are even enhanced in the absence of IL-2. Regulatory T cells favor IL-17 production but prevent the disease when administered early in the course by suppressing expansion of T cells. Thus, the pathogenic or protective effects of cytokines and the therapeutic capacity of regulatory T cells are crucially dependent on the timing and the nature of the disease.     

系统性红斑狼疮患者疾病活动度与血清铁蛋白的关系

目的探究系统性红斑狼疮患者疾病活动度与血清铁蛋白(FET)的关系。方法选取2013年3月至2014年3月于惠东县妇幼保健院进行治疗的系统性红斑狼疮(SLE)患者40例,按疾病的活动度分为稳定期组和活动期组,各20例,同时选取健康志愿者20例纳入对照组。比较3组受试者FET、抗双链DNA(ds-DNA)抗体水平及SLE疾病活动度指标(SLEDAI)评分。结果稳定期组和活动期组FET、ds-DNA抗体水平明显高于对照组,活动期组FET、ds-DNA抗体水平及SLEDAI评分明显高于稳定期组,差异均有统计学意义(P0.05)。稳定期组与活动期组患者FET异常率分别为40%、90%,差异有统计学意义(P0.05)。SLE患者FET水平与ds-DNA抗体、SLEDAI评分均呈正相关(r分别为0.541、0.620,P0.05)。治疗后2组患者FET升高例数较治疗前均下降,FET水平均降低,治疗前后差异均有统计学意义(P0.05)。结论 FET水平与SLE患者疾病活动度呈正相关,可以将其作为诊断SLE的可靠指标。     

PCT等炎性指标在儿童细菌性中枢神经系统感染诊断中的研究进展

目的:探讨PCT等炎性指标在儿童细菌性中枢神经系统感染(CNSI)性疾病诊断中的应用,评估其在细菌性脑膜炎和病毒性脑膜炎中的临床诊断及鉴别诊断价值。方法:通过检索《万方医学数据库》、《中国知网》、《PubMed》等数据库关于CNSI实验室诊断指标的临床价值研究的相关文献。结果:共选用27篇中枢神经系统感染实验室检查指标相关文献。结论:血清及脑脊液中CRP、PCT、NSE、IL-6、TNF-α等炎性指标在鉴别诊断小儿CNSI方面具有重要意义。多项指标联合应用能提高CNSI诊断及鉴别诊断。     

Procalcitonin testing for diagnosis and short-term prognosis in bacterial infection complicated by congestive heart failure: a multicenter analysis of 4,698 cases

Introduction

Procalcitonin (PCT) is a biomarker for the clinical diagnosis of bacterial infection that is more specific and earlier than fever, changes in white blood cell count, and blood cultures. Congestive heart failure is an important cause of endotoxin resorption from the intestine, which significantly increases PCT expression in noninfected patients with heart failure. The diagnostic performance and cut-off value of PCT in patients with bacterial infection complicated by congestive heart failure needs to be confirmed.

Methods

A total of 4,698 cases from different cities in China, including those with different classes of congestive heart failure, bacterial infection, bacterial infection complicated by heart failure and healthy individuals, were chosen for the diagnostic value analysis of PCT and screening candidate predictors of mortality in subjects with bacterial infection complicated by congestive heart failure.

Results

Patients with simple heart failure had significantly higher PCT levels than normal controls (P < 0.01), whereas patients with bacterial infection complicated by congestive heart failure had significantly higher PCT levels than those with simple infection (P < 0.01). Although it was useful for the diagnosis of infection (area under the receiver operating characteristic curve >80%), the positive predictive value of PCT decreased significantly with increasing severity of heart failure (P < 0.05), and the cut-off value of PCT concentrations for infection complicated by classes II, III and IV heart failure were 0.086, 0.192 and 0.657 μg/L, respectively. Heart failure degree, PCT level, and age were the candidate predictors of mortality in patients with bacterial infection complicated by congestive heart failure.

Conclusions

These data suggest that complicated heart failure elevates the PCT level in patients with bacterial infection. Thus, the results of the PCT test must be analyzed correctly in consideration of the severity of heart failure. Close attention should be paid to cardiac function and PCT expression in aged patients with infection complicated by congestive heart failure.     

Intravenous immunoglobulin for ANCA-associated systemic vasculitis with persistent disease activity

Intravenous immunoglobulin (IVIg) is a potential alternative treatment for anti-neutrophil cytoplasm antibody (ANCA)-associated systemic vasculitis (AASV) with less toxicity than conventional immunosuppressive agents. This randomized, placebo-controlled trial aimed to investigate the efficacy of a single course of IVIg (total dose 2 g/kg) in previously-treated AASV with persistent disease activity in whom there was an intention to escalate therapy. Vasculitic activity was monitored by the Birmingham vasculitis activity score (BVAS), C-reactive protein (CRP) and ANCA levels. Treatment response was defined as a reduction in BVAS of more than 50% after 3 months, and there was an intention to keep doses of concurrent immunosuppressive drugs unchanged during this period; follow-up continued to 12 months. Seventeen patients were randomized to receive IVIg and 17 to receive placebo. Treatment responses were found in 14/17 and 6/17 of the IVIg and placebo groups, respectively (p=0.015, OR 8.56, 95%CI 1.74-42.2). Following infusion of trial medication, greater falls in CRP were seen at 2 weeks (p=0.02) and 1 month (p=0.04) in the IVIg group. No differences were observed between ANCA levels or cumulative exposure to immunosuppressive drugs, and after 3 months there were no differences in CRP levels or disease activity between the IVIg and placebo groups. Seventeen adverse effects occurred after IVIg and six after placebo: they were mostly mild, although reversible rises in serum creatinine occurred in four from the IVIg group. A single course of IVIg reduced disease activity in persistent AASV, but this effect was not maintained beyond 3 months; mild, reversible side-effects following IVIg were frequent. IVIg is an alternative treatment for AASV with persistent disease activity after standard therapy.