Purpose: Borrelia burgdorferi, the etiologic agent of Lyme disease, has rarely been successfully cultured from blood. We report on seven patients from Westchester County, New York, with B. burgdorferi bacteremia diagnosed between April 1987 and August 1987.
Patients and methods: One hundred thirty-two attempts to isolate spirochetes were made on blood specimens obtained from 104 patients. Twenty-two of these specimens were obtained from nine patients who had recently been bitten by Ixodes ticks but who were asymptomatic. Heparinized blood or serum specimens (0.2 to 0.4 mL) were inoculated onto 6 mL of modified Barbour-Stoenner-Kelly medium. Lyme serology was performed by enzyme-linked immunosorbent polyvalent, IgM, and IgG assays, fluorescent immunoassay, and microhemagglutination.
Results: Four of the seven patients had erythema migrans, two had facial nerve palsy, and one had a flu-like syndrome without rash. These patients represented 21% (four of 19) of all patients with the characteristic skin lesion who had blood cultures for B. burgdorferi, and 40% (two of five) of all those with facial nerve palsy. Serologic testing was frequently nonreactive; two patients had no detectable antibody on multiple sera by five different assays. All patients improved with antibiotic treatment, and had negative subsequent blood cultures, but five of seven had persistent complaints after completion of therapy.
Conclusion: Culturing blood for B. burgdorferi may be useful in confirming the diagnosis of Lyme disease in selected patients. Use of spirochete blood cultures may facilitate a better understanding of the pathogenesis and natural history of Lyme disease.