Résumé
To assess whether systemic lupus [SLE] patients with levels of proteinuria <1000 mg/24h should be routinely biopsied, or we can depend on urinary adhesion molecules [ICAM-1 and VCAM-1] as markers for the severity of lupus nephritis [LN]. This study included 30 SLE patients with proteinuria <1000 mg/24h, and 20 SLE patients without proteinuria. Twenty healthy control subjects were also included. Basic laboratory parameter, RF, ANA, Anti-dsDNA, Complement C3 and C4, Urinary ICAM-1 and VCAM-1 and estimation urinary total proteins/24 hours were performed for each subject. Renal biopsy was also done in the indicated cases. Twenty three of thirty biopsies were diagnostic of lupus nephritis: 3 mild nephrosclerosis, 6 mesangial proliferation, 8 focal proliferative, 5 diffuse proliferative, and 1 membranous lupus nephritis. The levels of proteinuria were 94.5 +/- 22 mg/24h, 119 +/- 33 mg/24h and 725 +/- 180 mg/24h for control, patients without proteinuria and patients with proteinuria respectively. No statistical differences could be detected as regards to C3, C4, urinary ICAM-1 and urinary VCAM-1. Patients were reclassified according to the severity of renal histopathological changes into mildly and severely affected groups. We found no statistical differences between both groups as regards C3 and C4, but there were high statistical differences in urinary ICAM-1 and urinary VCAM-1 [P value <0.0005]. Our findings suggest that renal biopsy should be performed in these patients in the presence of new onset or rising proteinuria to enable prompt diagnosis of LN and initiation of treatment earlier in the course of the disease