SYSTEMIC-SCLEROSIS AND IMPOTENCE - A CLINICOPATHOLOGICAL CORRELATION

A hypothesis of the mechanism of systemic sclerosis associated impoten ce was developed by making a clinicopathological correlation between t he results of preoperative erectile function testing and those of path ological examination of excised erectile tissue in an impotent man wit h systemic sclerosis. Preoperative examination revealed firm corporeal tissue with diminished penile stretch capability. Pharmacocavernosome try/pharmacocavernosography under conditions consistent with trabecula r smooth muscle relaxation revealed severe diffuse corporeal venoocclu sive dysfunction. During penile implantation surgery the compact erect ile tissue was unable to be dilated and required sharp corporeal tissu e excision under direct vision to achieve cylinder insertion. Histolog ical investigation of the excised corporeal tissue demonstrated severe corporeal fibrosis. Computer assisted color histomorphometry revealed that the mean percentage of trabecular smooth muscle area to total er ectile tissue area was 18.2 +/- 13.9% (normal 40 to 52). Immunohistoch emical staining with desmin, a protein found in smooth muscle, verifie d prolific corporeal fibrosis. In situ hybridization of the corporeal tissue demonstrated messenger ribonucleic acid collagen and fibronecti n messenger ribonucleic acid expression. Strong hybridization signals were found in mesenchymal cell types, including trabecular smooth musc le cells. In summary, clinicopathological correlation revealed that ve no-occlusive dysfunction and loss of penile length were secondary to t he excessive accumulation of extracellular matrix, partially due to tr abecular smooth muscle cells undergoing synthetic as opposed to contra ctile phenotypic activity.