Form variants of globular hyaline microthrombi. Light microscopy, immunohistochemical and scanning and transmission electron microscopy observations

Globular hyaline microthrombi are characterized by their diameter (2-30 micron), globular form, and positive PAS and PTAH reaction. They are a morphologic indicator of disturbed microcirculation and hemostasis, such as that occurring in shock. In two of our cases, we observed large globular hyaline microthrombi, some with central webbed degradation progressing to the formation of closed or open hollow globules. The electron microscopic findings were similar to those observed by other investigators in typical shock bodies. On the basis of the morphologic findings, the authors conclude that degradation phenomena start at the center of globular hyaline microthrombi and can progress to the surface where accelerated fibrinolysis is possible. The cellular elements that other investigators have described as a possible condensation center for fibrin precipitate proved to be structurally intact cells that are apparently located in niches of open hollow globules or in the center of circular hyaline microthrombi. The diagnostic relevance, vitality, and temporal classification are discussed.