Chief of Infectious Diseases, Veterans Affairs Medical Center, Northport, NY 11768, USA; Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA.
Stony Brook University School of Medicine, Stony Brook, NY, 11794, USA; Fellow in Infectious Diseases, Department of Infectious Diseases, Stony Brook University Hospital, Stony Brook, NY, 11794, USA.
Ticks Tick Borne Dis. 2019 Feb;10(2):407-411. doi: 10.1016/j.ttbdis.2018.12.003. Epub 2018 Dec 14.
In North America, Lyme disease (LD) is caused predominantly by the spirochete Borrelia burgdorferisensu stricto, and is transmitted by blacklegged ticks. Long Island, New York, is highly endemic for the disease. The C6 peptide (C6P) is currently used as a screening test for LD in our institution. Our objective was to examine how screening with C6P concorded with diagnosis of LD at the Veterans Affairs Medical Center, Northport, Long Island. A retrospective chart-review of 2558 C6P tests was performed during the period of 1/1/2010 to 12/31/2016. Patients were categorized by Lyme Disease (LD) or no LD groups. LD group was defined as having an erythema migrans (EM) rash, or ≥ 2 IgM bands or ≥ 5 IgG bands on immunoblot. Out of the 409 patients with positive or equivocal C6P, 181 patients with LD were based on presence of EM, or Western blot IgM and IgG test results; 228 did not have LD. The positive predictive value of C6P was 44.5%. EM was the most common presentation. In the LD group, history of tick bite (P: 0.0001), headache (P: 0.0036), joint swelling (P: 0.0086) and myalgias (P: 0.0005) were more likely to be present. Zip code mapping of our cases mirrored those previously reported in the Suffolk County Department of Health. In our review we encountered a significant number of false positive C6 assays. False positive C6P tests were ordered by primary care physicians (PCP) (37%) followed by neurologists (33%). A history of tick exposure and clinical findings of early Lyme disease such as headaches or joint aches were more likely to denote a true positive C6 peptide test. Rigorous education of physicians about Lyme disease and pitfalls of our available diagnostic tests are needed for their proper utilization.
在北美，莱姆病（LD）主要由伯氏疏螺旋体严格亚种引起，通过黑腿蜱传播。纽约长岛是该病的高度地方性流行区。C6 肽（C6P）目前被用作我们机构 LD 的筛选测试。我们的目的是检查 C6P 筛查与北港退伍军人事务医疗中心 LD 诊断的一致性，北港位于长岛。对 2010 年 1 月 1 日至 2016 年 12 月 31 日期间进行的 2558 次 C6P 检测的回顾性图表审查。患者分为莱姆病（LD）或无 LD 组。LD 组的定义为出现游走性红斑（EM）皮疹，或免疫印迹上至少有 2 条 IgM 带或至少有 5 条 IgG 带。在 409 例 C6P 阳性或可疑的患者中，根据 EM 或 Western blot IgM 和 IgG 检测结果，181 例患者存在 LD；228 例患者无 LD。C6P 的阳性预测值为 44.5%。EM 是最常见的表现。在 LD 组中，蜱叮咬史（P：0.0001）、头痛（P：0.0036）、关节肿胀（P：0.0086）和肌痛（P：0.0005）更常见。我们病例的邮政编码映射与 Suffolk 县卫生局之前报告的病例相吻合。在我们的审查中，我们遇到了大量的假阳性 C6 检测。初级保健医生（PCP）（37%）和神经科医生（33%）开具了大量的假阳性 C6P 检测。蜱暴露史和早期莱姆病的临床特征，如头痛或关节疼痛，更有可能表示 C6 肽检测呈阳性。需要对医生进行有关莱姆病的严格教育，并了解我们现有诊断测试的缺陷，以便正确使用这些测试。
