Goodman J L, Bradley J F, Ross A E, Goellner P, Lagus A, Vitale B, Berger B W, Luger S, Johnson R C
Department of Medicine, University of Minnesota School of Medicine, Minneapolis, USA.
Am J Med. 1995 Jul;99(1):6-12. doi: 10.1016/s0002-9343(99)80097-7.
The purposes of this study were to determine (1) the optimal techniques for and potential diagnostic usefulness of the polymerase chain reaction (PCR) in early Lyme disease, and (2) the true frequency and clinical correlates of PCR-documented blood-borne infection in the dissemination of Lyme disease.
We performed a prospective, controlled, blinded study of PCR, culture, and serology on fractionated blood samples from 105 patients; 76 with physician-diagnosed erythema migrans and 29 controls. Clinical characteristics of the patients were obtained with a standardized data entry form and correlated with results of the laboratory studies.
Only 4 of the 76 (5.3%) patients with erythema migrans were culture positive; however, 14 of 76 (18.4%) had spirochetemia documented by PCR of their plasma. None of 29 controls were PCR or culture positive (P = 0.007, versus patients). PCR-documented spirochetemia correlated with clinical evidence of disseminated disease; 10 of 33 patients (30.3%) with systemic symptom(s) were PCR positive compared to 4 of 43 (9.3%) without such evidence (P = 0.02). PCR positivity was more frequent among patients with each of four specific symptoms: fever, arthralgia, myalgia, and headache (all P < 0.05). A higher total number of symptoms (median 2.5 in PCR-positive patients versus 0 in PCR-negative controls; P < 0.01) and the presence of multiple skin lesions (37.5% of patients with multiple, versus 13.3% of patients with single lesions [P = 0.04] were also correlated with PCR positivity. Patients with both systemic symptoms and multiple skin lesions had a 40% PCR-positivity rate; however, 4 of 42 (9.5%) asympatomatic patients with only single erythema migrans lesions were also PCR positive. In multivariate analysis using logistic regression, the number of systemic symptoms was the strongest independent predictor of PCR positivity (P = 0.004).
PCR detection of Borrelia burgdorferi is at least three times more sensitive than culture for identifying spirochetemia in early Lyme disease and may be useful in rapid diagnosis. PCR positivity significantly correlates with clinical evidence of disease dissemination. Bloodstream invasion is an important and common mechanism for the dissemination of the Lyme disease spirochete.
本研究的目的是确定（1）聚合酶链反应（PCR）在早期莱姆病中的最佳技术及其潜在诊断价值，以及（2）在莱姆病传播过程中，PCR检测到的血行感染的实际发生率及其临床相关因素。
我们对105例患者的分馏血样进行了一项关于PCR、培养和血清学的前瞻性、对照、盲法研究；其中76例为医生诊断的游走性红斑患者，29例为对照。通过标准化数据录入表格获取患者的临床特征，并将其与实验室研究结果相关联。
76例游走性红斑患者中只有4例（5.3%）培养阳性；然而，76例中有14例（18.4%）血浆PCR检测证实有螺旋体血症。29例对照者PCR或培养均为阴性（与患者相比，P = 0.007）。PCR检测到的螺旋体血症与播散性疾病的临床证据相关；有全身症状的33例患者中有10例（30.3%）PCR阳性，而无此类证据的43例患者中有4例（9.3%）PCR阳性（P = 0.02）。在有发热、关节痛、肌痛和头痛这四种特定症状的患者中，PCR阳性更为常见（所有P < 0.05）。症状总数较多（PCR阳性患者中位数为2.5个，PCR阴性对照者为0个；P < 0.01）以及存在多个皮肤病变（多个皮肤病变患者中占37.5%，单个皮肤病变患者中占13.3% [P = 0.04]）也与PCR阳性相关。既有全身症状又有多个皮肤病变的患者PCR阳性率为40%；然而，42例仅有无症状单个游走性红斑病变的患者中有4例（9.5%）PCR也呈阳性。在使用逻辑回归的多变量分析中，全身症状的数量是PCR阳性最强的独立预测因素（P = 0.004）。
在早期莱姆病中，PCR检测伯氏疏螺旋体在识别螺旋体血症方面的敏感性至少比培养高3倍，可能有助于快速诊断。PCR阳性与疾病播散的临床证据显著相关。血行侵袭是莱姆病螺旋体传播的一种重要且常见的机制。
