ERYTHEMA CHRONICUM MIGRANS - AN ELECTRON-MICROSCOPIC STUDY

Spirochaetal organisms are found in skin specimens obtained by biopsy from a erythema chronicum migrans lesion. The histological picture sho ws a logical localization of a lymphohistiocytic cell infiltrate: deep dermal in the central papule and superficial in the erythematous bord er. The electron-microscopic characteristics of the micro-organisms in these specimens (regular waving appearance with coils every 0.8-1.2 m um, oblique striation of periplasmatic fibrils, cross-section of 0.3 m um, membranes) correspond to the spiral-like structure of Borreliae is olated from blood. The Borreliae seem to move freely through the matri x of the dermis and are not phagocytized. This brings on the typical c linical picture of the centrifugally spreading erythematous band.