Meningoencephalitis from Borrelia miyamotoi in an Immunocompromised Patient

Abstract

Ixodes ticks serve as vectors for Borrelia burgdorferi, the agent of Lyme disease.Globally, these ticks often concurrently harbor B. miyamotoi, a spirochete that is classified within the relapsing-fever group of spirochetes.Although humans presumably are exposed to B. miyamotoi, there are limited data suggesting disease attributable to it.We report a case of progressive mental deterioration in an older, immunocompromised patient, and even though Koch's postulates were not met, we posit B. miyamotoi as the cause, owing to its direct detection in cerebrospinal fluid (CSF) with the use of microscopy and a polymerase-chain-reaction (PCR) assay.It is likely that B. miyamotoi is an underrecognized cause of disease, especially in sites where Lyme disease is endemic. C A SE R EP OR TAn 80-year-old woman was evaluated because of 4 months of progressive decline in mental status, including increasing confusion, withdrawal from family interactions, episodes of not getting out of bed, wobbling gait, and difficulty hearing, accompanied by a decrease in appetite and a 13.6-kg (30-lb) weight loss.Her medical history was notable for non-Hodgkin's lymphoma (follicular type, stage IIA), diagnosed in February 2005.She was treated with a regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone with rituximab from June 2005 through September 2005, and then with rituximab every 6 months until August 2011.The patient also had a history of hypertension and a recent diagnosis of depression.She had no history of travel, no known tick bites or rash, and no recent erythema migrans.She lived on a farm in New Jersey, where there was possible exposure to poultry, cats, dogs, and field mice and where deer were frequently observed.She had been treated twice in the past for Lyme disease: once in November 2006 (clinical details were not available other than a negative result on serologic testing for Lyme disease) and once in July 2007, when she presented with erythema migrans and was treated with doxycycline for 2 weeks.The patient was evaluated by her primary care provider.A metabolic workup was unrevealing, and she was referred to the oncology department.Computed tomography of the chest, abdomen, and pelvis showed no evidence of new disease.Magnetic resonance imaging of the brain, performed with and without the administration of contrast material on February 6, 2012, showed no acute findings.A lumbar puncture was performed on February 21, 2012, to assess the patient for lymphomatous meningitis.Cytologic analysis and flow cytometry showed pleocytosis with an increased protein level (Table 1).Giemsa staining of a cytospin