Association Between Infectious Burden And Cerebral Microbleeds: A Pilot Cross-Sectional Study

Objective: Cerebral microbleeds (CMBs) is a subtype of cerebral small vessel disease. Their underlying pathogenesis remains unclear. The aim of this study was to investigate the association between infectious burden (IB) and CMBs. Methods: Seven hundred and seventy-three consecutive patients who were hospitalized in the Department of Neurology in General Hospital of Western Theater Command without severe neurological symptoms were recruited and selected in this pilot cross-sectional study. CMBs were assessed using the susceptibility-weighted imaging sequence of magnetic resonance imaging. Immunoglobulin G antibodies against common pathogens, including herpes simplex virus (HSV)-1, HSV-2, cytomegalovirus (CMV), Chlamydia pneumoniae (C. pneumoniae), Mycoplasma pneumoniae (M. pneumoniae), Epstein-Barr virus (EBV), Helicobacter pylori (HP), and Borrelia burgdorferi (B. burgdorferi), were measured by commercial ELISA assays. IB was defined as a composite serologic measure of exposure to these common pathogens. Results: Patients with and without CMBs were defined as the CMBs group (n = 76) and the non-CMBs group (n = 81), respectively. IB was significantly different between the CMBs and non-CMBs groups. After adjusted for other risk factors, the increased IB was independently associated with the presence of CMBs (P = 0.031, OR = 3.00, 95% CI [1.11-8.15]). IB was significantly positively associated with the number of CMBs (Spearman rho = 0.653, P < 0.001). The levels of serum inflammatory markers were significantly different between the CMBs and non-CMBs groups and among the categories of IB. Interpretation: IB consisting of HSV-1, HSV-2, CMV, C. pneumoniae, M. pneumoniae, EBV, HP, and B. burgdorferi was associated with CMBs. All the findings suggested that pathogen infection could be involved in the pathogenesis of CMBs.