Light and electron microscopic differentiation of amyloid and colloid or hyaline bodies.

Hyaline or colloid bodies (Civatte bodies) and amyloid are sometimes confused because of their similar appearance under the light microscope. A differentiation can be made by histochemical means (DMAB-Nitrite method) and by fluorescence or polarization microscopy. At the ultrastructural level hyaline or colloid bodies as well as amyloid exhibit a fibrillar structure, but can be differentiated by the diameter and arrangement of fibrils and the localization of the aggregations. A clearcut differentiation between hyaline or colloid bodies and amyloid seems of great importance in any dicussion of the epidermal origin of amyloid and the classification of fibrillar aggregations associated with skin tumours.