Objective: Studies in literature on skin of patients with massive weight loss are limited and somehow conflicting in their results. The aim of this study was to quantitatively assess the skin change after massive weight loss.
Method: This study was performed on 30 patients from whom skin biopsies were taken from the skin excised during operations, divided into 3 main groups. The first included patients who were undergoing cosmetic contouring procedures without history of massive weight loss. The second included patients with morbid obesity, who were undergoing bariatric surgery. The third included patients with massive weight loss submitted to cosmetic contouring procedures after stable weight reduction for 6 months. Biopsies were taken from the skin for histological testing. Hematoxylin and Eosin, Mallory, and Aldehyde fuchsin Stains were used to assess the skin collagen and elastic fibers. For quantitative assessment, the Image Analyzer System (Leica Q 500 MC program) was employed. Tensile tests were applied to skin samples using (Instron 5500R) Universal testing machine to measure the skin tensile strength to determine the maximum stress (Burst strength) that skin can induce before damage.
Results: Collagen was significantly thinner in massive weight loss group in both papillary and reticular dermis and significantly less dense in reticular dermis with damage to the elastic fiber network.
Conclusion: The skin of the patients with massive weight loss is weak due to lower density and thickness of collagen fibers and damage to its elastic fibers.
Keywords: collagen; image analyzer; massive weight loss; obesity; skin laxity.