[A case of IgA nephropathy with numerous interstitial foam cells--analysis of infiltrating mononuclear leucocytes in renal tissue].

A 27-year-old female was admitted to our hospital in order to examine proteinuria and microscopic hematuria. Light microscopic findings of her kidney showed proliferation of mesangial cells and numerous interstitial foam cells. Immunofluorescent and electron microscopic findings revealed IgA nephropathy. Immunoperoxidase studies using monoclonal antibodies disclosed that interstitial foam cells were positive for antibodies of the monocyte/macrophage lineage and also expressed adhesion molecules (CD11a, b, c, LFA-1) and MHC-class II antigens. Hereditary nephritis as Alport syndrome was negated by her familial history and electron microscopic study. We considered that it was a rare and interesting case with numerous interstitial foam cells, because the patient did not have hyperlipidemia as in nephrotic syndrome.