Urinary glycosaminoglycans in systemic lupus erythematosus: marker of renal affection and relation to disease activity

ABSTRACT

To evaluate glycosaminoglycans [GAG], heparan sulphate [HS] and chondroitin sulphate [CS] levels in the urine of systemic lupus erythematosus [SLE] patients. Also, to determine its possible use as a marker for lupus nephritis and its correlation with disease activity. This study was conducted on 30 patients suffering from SLE. They were subdivided according to disease activity and renal affection. Ten apparently healthy subjects were taken as a control group. GAGs were isolated from urine with ion exchange chromatography on DEAE sephacel. Determination of HS and CS levels were done with ELISA. There was a significant increase of GAGs and HS levels in SLE patients than in controls [p<0.05]. There was a highly significant difference [p<0.01] between active and inactive SLE patients as regards CS/HS ratio. GAGs and CS/HS ratio were significantly higher in active patients with lupus nephritis [p< 0.001]. Urinary GAGs may represent an additional, non-invasive diagnostic approach for lupus nephritis. It could be used as a parameter for disease activity and lupus nephritis