Mesangial Hyaline Droplet Formation and Mesangiolysis in the Renal Glomeruli Seen in Pigs with Mastocytosis

Abstract

Light and immunofluorescent microscopical examination was performed on the kidneys of 16 pigs with mastocytosis. Hyaline droplets were demonstrated in various degrees in the mesangium of the glomeruli of all the pigs. In many of the pigs, the hyaline droplets were also present in the macula densa and juxta-glomerular zone. These hyaline droplets resembled those in the proximal tubular epithelium both in shape and staining property. By immunofluorescence, IgG was demonstrated in the glomerular hyaline droplets, but C3 was not detected. Severe global or segmental expansion of the mesangial area with mesangiolysis was noted in 10 pigs. The hyaline droplet formation were occurred more frequently in association with mesangiolysis. The glomerular lesions were not considered to be specific to mastocytosis and possible pathogenesis of the lesions were discussed.