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 ρ = 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.