A case of systemic lupus erythematosus showing invagination of the podocyte into the glomerular basement membrane: an electron microscopic observation of a repeated-renal biopsy.

A case of systemic lupus erythematosus (SLE) showing invagination of glomerular epithelial cells into the glomerular basement membrane (GBM) has been reported. The patient was a 30-year-old woman who was diagnosed with SLE at the age of 25 and had been medicated with corticosteroid. At the age of 30, she was re-admitted into our hospital because of the relapse of lupus nephritis. Renal biopsy was performed twice: at the onset of SLE and the second admission. Morphologically, the results of the first and second renal biopsies were compatible with the classification of lupus nephritis class II. Immunofluorescent study revealed the mesangial deposition of IgG, IgA, C1q, C3 and membrane attack complex (MAC) in two renal biopsies. Especially, in the second renal biopsy, numerous vesicular structures composed of a unit membrane going into the epithelial site of the GBM were observed by electron microscopy (EM), but not in the first renal biopsy. Moreover, observations of serial sections of EM suggested that these vesicular structures were invaginated into the GBM and derived from a part of the podocytes.

[Case of primary antiphospholipid antibody syndrome with repeated renal biopsies].

Antiphospholipid antibody syndrome (APS) is characterized by the presence of repeated arterial and venous thrombosis, recurrent fetal loss and thrombocytopenia. Recently, renal involvement associated with APS is being increasingly recognized and discussed. In most cases, there has been a vascular nephropathy characterized by small vessel vaso-occulusive lesions associated with fibrous intimal hyperplasia of the interlobular arteries, thrombosis and focal cortical atrophy. We report a case of a 38-year-old patient with primary APS. Renal biopsies were performed three times in 26 years. Various glomerular and vascular lesions associated with APS were observed and discussed.