A comparison of the fraction of collagen and elastic fibers by image analysis in scleredema

Abstract

Background: Scleredema is a rare connective tissue disorder, characterized by hard and thick skin. It is well known that collagen synthesis is increased in scleredema skin, but there has been no study on the change of elastic fibers. Objective: The purpose of this study was to compare the changes of collagen and elastic fibers in scleredema and normal skin. Methods: We retrospectively evaluated the biopsy specimens of 10 patients diagnosed with scleredema. The control group was selected by matching each scleredema case with same site and similar ages from the biopsy specimens which showed normal dermis. A computerized image analysis system was used to measure the fraction of collagen and elastic fibers and calculate the ratio of elastic fibers to collagen fibers in each group. Results: The skin of scleredema was found to have a significant increase in the percentage of collagen fibers in the dermis compared to the control group. On the other hand, the percentage of elastic fibers was significantly decreased in the scleredema group (p < 0.05). Conclusion: In contrast to scleroderma which shows an increase in dermal elastic tissue and collagen fibers, we concluded that there is a decrease of elastic fibers in scleredema and that the pathogenesis and molecular involvement are different in the two diseases, we also found that the computerized image analysis system was a useful tool in the measurement of connective tissue components.