The histology and immunohistochemistry of free buccal mucosa and full-skin grafts after exposure to urine

Abstract

Objective. To investigate the histological and immunohistochemical behaviour of free buccal mucosa and full-skin grafts after exposure to urine. Materials and methods. A buccal mucosal graft and a full-skin graft were freely transferred into the bladder of 12 minipigs, after stripping the bladder mucosa. Endoscopic investigations were carried out 2 and 5 months after surgery, and the grafts examined after death at 7 months, both histologically and immunohistochemically. Results. Shrinkage of the full-skin graft was apparent endoscopically in five cases. Of the nine full-skin grafts, four showed severe inflammatory reactions, two necrosis and two ulcerations. Conversely, the 10 buccal mucosal grafts had fewer pathological findings (three minimal inflammation and three with scars) and a pronounced similarity on immunohistochemistry. Conclusion. The buccal mucosal graft showed significantly fewer adverse histopathological findings after long-term exposure to urine than the full-skin graft and is therefore a preferable material for urethral reconstruction.