Two cases of systemic lupus erythematosus accompanied by antiphospholipid syndrome nephropathy without immune complex nephritis

We report here two interesting cases of systemic lupus erythematosus (SLE) accompanied by antiphospholipid syndrome nephropathy (APSN). These cases satisfied the criteria for SLE established by the American College of Rheumatology 1997 and also satisfied the criteria for antiphospholipid syndrome (APS) established by the Sapporo International Workshop of APS 1998. Both cases had high blood pressure with elevated plasma renin activity, proteinuria and renal dysfunction. Their biopsied renal specimens showed the characteristic findings for APSN, such as mesangial proliferation, double contours, thickening of the capillary loops, and intimal hyperplasia, but there was no evidence for immune complexes in the glomeruli, which were examined by the indirect immunofluorescence methods and the electron microscopy method. These results indicated that their renal dysfunction was caused by APSN, but not by immune complex nephritis. In addition to treatment with prednisolone, they were administered anticoagulants (warfarin, or aspirin, or heparin) for APSN and an angiotensin II receptor blocker, candesartan, for the hypertension. Subsequently, their conditions recovered with the improvement of renal function and hypertension. Our experiences suggest that anticoagulant therapy in addition to corticosteroids offers advantages in the treatment of patients with SLE accompanied by APSN and renal dysfunction.