X-ray microprobe analysis of Michaelis-Gutmann bodies in human and experimental malakoplakia.

Using x-ray microprobe analysis, we studied Michaelis-Gutmann bodies (M-G bodies) in malakoplakia tissue samples from human kidney and testis as well as from lesions experimentally induced in the rat. In all the M-G bodies tested we could unambiguously detect calcium at both its Kalpha and Kbeta lines. The actual amount of calcium depended on the developmental state, ie, on the degree of calcification of the M-G body, In M-G bodies of rat kidney malakoplakia tissue fixed without osmium tetroxide, the phosphorus could also be detected unambigously. From the ratios of calcium and phosphorus percentages (w/w) we concluded that CaHPO4 was present. No difference was found between M-G bodies in malakoplakia tissues of human origin and those in experimentally induced malakoplakia.