ABSTRACT
Neuropsychiatric manifestations of systemic lupus erythromatosus [SLE] are common and its pathogenesis is still unclear but recent neuroimaging studies in SLE attributed it to vasculitic processes which results in cerebral ischemia. Matrix metelloproteinase-9 [MMP9] has a central role in ischemic damage of the brain, it disrupts the blood brain barrier [BBB] and it also induces a high breakdown capacity in arteriolar basement membrane leading to cerebral edema and secondary hemorrhage. Also it participates in the degradation of myelin basic protein which is a major component of both central and peripheral nervous system. This study was performed to evaluate the possible association between serum MMP9 and neuropsychiatric manifestation with cerebral MRI abnormalities in patients with SLE. Serum MMP9 levels were determined in forty patients with systemic lupus erythromatosus and twenty apparently healthy controls who underwent clinical examination, neurological examination and neuropsychological testing. Cerebral MRI scans with T[1] and T[2] weighted lesions were performed for all subjects. In addition, immunological assay and routine investigations were performed. SLE patients with neuropsychiatric manifestations [NP-SLE] had significantly higher serum MMP9 concentrations than patients without neuropsychiatric manifestations [NNP-SLE], and those with cognitive deficits had significantly higher concentrations of serum MMP9. Furthermore MMP9 levels were significantly higher in patients with T[1] and T[2] weighted lesions in cerebral MRI in NP-SLE. Elevated levels of serum MMP9 in patients with SLE may reflect neuropsychiatric involvement particularly cognitive dysfunction and MRI results favor the association between serum MMP9 levels and ischemic changes with increased risk of cerebral ischemic events in SLE patients