Seronegative Lyme neuroborreliosis in a patient treated by rituximab

Laboratory Diagnosis of Lyme Borreliosis

Lyme borreliosis is caused by a growing list of related, yet distinct, spirochetes with complex biology and sophisticated immune evasion mechanisms. It may result in a range of clinical manifestations involving different organ systems, and can lead to persistent sequelae in a subset of cases. The pathogenesis of Lyme borreliosis is incompletely understood, and laboratory diagnosis, the focus of this review, requires considerable understanding to interpret the results correctly. Direct detection of the infectious agent is usually not possible or practical, necessitating a continued reliance on serologic testing. Still, some important advances have been made in the area of diagnostics, and there are many promising ideas for future assay development. This review summarizes the state of the art in laboratory diagnostics for Lyme borreliosis, provides guidance in test selection and interpretation, and highlights future directions.

Tick-Borne Pathogens Detected in the Blood of Immunosuppressed Norwegian Patients Living in a Tick-Endemic Area

BACKGROUND

The knowledge regarding the occurrence and the clinical implications of tick-borne infections in immunosuppressed patients living in tick-endemic areas is limited.

METHODS

Adult patients with autoimmune conditions requiring immunosuppressive treatment such as infliximab and rituximab, were invited to participate in the study when they attended the hospital for treatment and/or control of the disease. Whole blood samples were analysed by real-time PCR for Borrelia burgdorferi s.l., Borrelia miyamotoi, Anaplasma phagocytophilum, Rickettsia spp., Candidatus Neoehrlichia mikurensis and Babesia spp.

RESULTS

The occurrence of tick-borne pathogens in the blood of patients (n=163) with autoimmune conditions requiring immunosuppressive treatment were evaluated. Pathogen DNA was detected in 8.6% (14/163) of the patients. The predominant pathogen was Candidatus Neoehrlichia mikurensis (12/14), which was carried in the blood of infected patients for 10-59 days until treatment with doxycycline. Borrelia burgdorferi sensu lato and Rickettsia spp. were detected in one patient each. The B. burgdorferi-infected patient presented with fever, whereas the remaining patients were judged to have subclinical infections. Borrelia miyamotoi, Anaplasma phagocytophilum, and Babesia spp. were not detected in any patient.

CONCLUSIONS

Patients treated with biologicals and living in a tick-endemic area seem to have a high risk of contracting Ca. Neoehrlichia mikurensis infection which if left untreated could result in thromboembolic complications.

Erythema Migrans: Course and Outcome in Patients Treated With Rituximab

Background

Information on Lyme borreliosis (LB) in patients treated with rituximab is limited to individual case reports.

Methods

We reviewed data on adult patients diagnosed with typical erythema migrans (EM) at the LB outpatient clinic of the University Medical Center Ljubljana, Slovenia, in the 10-year period 2008–2017. For all patients, clinical and laboratory information was acquired prospectively using a standardized questionnaire.

Results

Among 4230 adult patients with a diagnosis of EM, 7 patients (0.17%), 5 women and 2 men with a median age of 65 years (range, 55–66 years), were receiving rituximab for an underlying medical condition. In these 7 patients, signs of disseminated LB (43%) and the isolation rates of borreliae from blood before antibiotic treatment (40%) were unusually high compared with corresponding findings in immunocompetent patients who had EM diagnosed at the same institution (8% vs <2%, respectively). The rates of LB-associated constitutional symptoms and borrelial antibodies in serum were lower than expected (14% and 29%, respectively, in patients receiving rituximab vs 25% and 65% in immunocompetent patients). One of the 7 patients (14%) experienced treatment failure; nevertheless, the outcome of early LB 1 year after antibiotic treatment, as used for immunocompetent patients with EM, was excellent in all 7 patients.

Conclusions

Findings in 7 patients with EM who were receiving rituximab for underlying disease suggest that although early LB in these patients is more often disseminated than in immunocompetent patients, the outcome 1 year after antibiotic treatment, as used for immunocompetent patients, is excellent.