Concurrent infection of the central nervous system by Borrelia burgdorferi and Bartonella henselae: evidence for a novel tick-borne disease complex.

OBJECTIVES To investigate Bartonella henselae as a potential human tick-borne pathogen and to evaluate its role as a coinfecting agent of the central nervous system in the presence of neuroborreliosis. DESIGN Case report study. SETTING A primary health care center in Flemington, NJ, and the Department of Research and Development at Medical Diagnostic Laboratories LLC in Mt Laurel, NJ. SUBJECTS Two male patients (aged 14 and 36 years) and 2 female patients (aged 15 and 30 years, respectively) with a history of tick bites and Lyme disease. MAIN OUTCOME MEASURES Laboratory and diagnostic findings before and after antimicrobial therapy. RESULTS Patients residing in a Lyme-endemic area of New Jersey with ongoing symptoms attributed to chronic Lyme disease were evaluated for possible coinfection with Bartonella species. Elevated levels of B henselae-specific antibodies were found in these patients using the immunofluorescent assay. Bartonella henselae-specific DNA was detected in their blood. None of these patients exhibited the clinical characteristics of cat-scratch disease. Findings of cerebrospinal fluid analysis revealed the presence of both B henselae- and Borrelia burgdorferi-specific DNA. Bartonella henselae-specific DNA was also detected in live deer ticks obtained from the households of 2 of these patients. CONCLUSIONS Our data implicate B henselae as a potential human tick-borne pathogen. Patients with a history of neuroborreliosis who have incomplete resolution of symptoms should be evaluated for B henselae infection.