Objective: To clarify the localization, distribution, content and type of collagen in the myocardium of patients with Keshan disease (KD).
Methods: Picrosirium red staining, polarization microscopy and image analysis were used to study autopsy specimens from 335 KD patients.
Results: A loose network of collagen and a higher ratio of type III collagen were found in the myocardial scar tissues of acute KD patients. In the myocardial scar tissues from chronic KD patients, the collagen fibers were dense, the ratio of type I collagen was higher, the ratio of type I to type III is increased in chronic KD and decreased in acute KD. The amount of collagen in non-necrotic regions was significantly higher than that of the controls.
Conclusion: The degeneration and necrosis of myocytes in KD is associated with disorders of collagen metabolism and with structural modelling of collagen.