Villumsen Steen, Jørgensen Charlotte Svaerke, Smith Birgitte, Uldum Søren, Schiellerup Peter, Krogfelt Karen Angeliki
Statens Serum Institut, Department of Bacteriology, Mycology, and Parasitology, Copenhagen, Denmark.
Diagn Microbiol Infect Dis. 2009 Oct;65(2):93-8. doi: 10.1016/j.diagmicrobio.2009.06.004.
Q fever is a ubiquitous zoonosis caused by Coxiella burnetii. The disease is emerging in many parts of the world, likely because of increased awareness and availability of better diagnostics. The diagnosis is primarily based on serology. Because the prevalence of the disease varies worldwide, the establishment of local cutoff values is needed. A baseline for antibodies against C. burnetii in Denmark was defined by testing sera from healthy Danish volunteers using a commercially available immunofluorescence antibody test. Cross-reactivity was studied on sera obtained from patients experiencing clinically related diseases. The cutoff titers suggested by the manufacturer were found to result in very low specificity of the test. The specificity was, however, effectively increased by using cutoff titers based on the local baseline and equal to immunoglobulin M (IgM) phase I > or =128, IgM phase II > or =256, IgG phase I > or =512, and IgG phase II > or =1024.
Q热是一种由伯氏考克斯体引起的全球性人畜共患病。该疾病在世界许多地区不断出现，这可能是由于人们的认识提高以及更好的诊断方法的可用性增加。诊断主要基于血清学。由于该疾病的患病率在全球范围内有所不同，因此需要建立当地的临界值。通过使用市售免疫荧光抗体试验检测丹麦健康志愿者的血清，确定了丹麦针对伯氏考克斯体抗体的基线。对患有临床相关疾病患者的血清进行了交叉反应性研究。发现制造商建议的临界滴度导致该试验的特异性非常低。然而，通过使用基于当地基线且等于免疫球蛋白M（IgM）I期≥128、IgM II期≥256、IgG I期≥512和IgG II期≥1024的临界滴度，特异性得到了有效提高。
