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.