Renal malakoplakia. Experimental production and evidence of a link with interstitial megalocytic nephritis.

The intrarenal injection of Boivin antigen is followed by the development of true melakoplakic lesions as characterised by the accumulation of macrophages containing MG bodies. Similarly the injection of diluted antigen is followed by the accumulation of macrophages with a granular PAS-positive cytoplasm but lacking MG bodies. These experimental models are compared with typical human renal malakoplakia and that entity known as megalocytic interstitial nephritis.