The significance of antibodies to anti-coagulation related factors and anti-phospholipid antibodies in glomerular microthrombosis in lupus nephritis:a prospective study on 124 patients / 中华风湿病学杂志

ABSTRACT

Objective To investigate the prevalence of glomerular microthrombosis in lupus nephritis (LN) and the significance of antibodies to anti-coagulation related factors and anti-phospholipid antibodies in glomerular microthrombosis (GMT).Methods Kidney biopsy specimens and plasma samples were obtained consecutively from 124 patients with LN. Kidney biopsy specimens were examined for the presence of glomerular microthrombi.Plasma samples from 25 LN patients with GMT (LN-GMT group) and 99 LN patients without GMT (LN-non-GMT group) were tested for lupus anticoagnlant (LA) and antibodies to cardiolipin (ACL),β2 glycoprotein I (β2GP I ),plasmin,thrombin,tissue plasminogen activator (t-PA) and Annexin A II.Results The prevalence of GMT in LN patients was about 20.2%.Compared to LN-non-GMT group,LN-GMT group had elevated SLE disease activity indices (SLEDAI),elevated activity and chronicity indices of kidney tissue injury,and elevated serum creatinine,blood urea nitrogen and proteinuria levels,and also had a higher frequency of hypertension (P＜0.01).The positive rates of LA,IgG class anti-β2GP I and anti-thrombin antibodies were higher in LN-GMT group than in LN-non-GMT group (P＜0.05).The positive rates of IgG class antibodies to ACL,plasmin,t-PA and Annexin A II in LN-GMT group were not statistically different from those in LN-non-GMT group (P＞0.05).No difference was found in the positive rate of any IgM class antibody between the two groups (P＞0.05).Conclusion This study has shown that GMT occurs approximately in 20.2% of the LN patients.Patients with GMT have more severe kidney tissue injury and more poor renal outcomes than patients without GMT.LA and antibodies to β2GP I and thrombin play a role in glomerular microthrombosis in lupus nephritis.