Connective tissue alterations in women with pelvic organ prolapse and urinary incontinence

Alterations in collagen synthesis and metabolism have previously been reported in patients with pelvic organ prolapse (POP) and/or urodynamic stress incontinence (USI). Since urinary incontinence does not always associate with POP, the objective of this study was to examine connective tissues from patients with USI plus POP, and patients with prolapse only.

Biopsies from the uterosacral ligaments were obtained during the operation from POP patients (n =28), and from continent women (control group, n =12) who underwent surgery for other benign reasons. POP patients were classified following urodynamic tests and symptom questionnaire with respect to the presence (n =14) or absence (n =14) of USI. N-terminal propeptides of collagen (PINP and PIIINP), TGF-beta and leptin were measured in plasma. Hydroxyproline and glycosaminoglycan (GAGs) concentrations and total hexosaminidase activity were measured in tissue samples. Histological sections were prepared using Masson's trichrome technique, and digitised solutions were used for imaging provided by Soft Imaging System GmBh. Statistical evaluations were made by the Kruskal-Wallis test.

A significant decrease in hydroxyproline content was found in USI+POP women in comparison to controls (p<0.05). In contrast, histopathological examination revealed an increased density of collagen in USI+POP patients. Hexosaminidase activity was decreased in both groups with POP, but no change in the amount of GAGs was observed. Markers of collagen synthesis (PINP, PIIINP), and factors related to the collagen synthesis (TGF-beta, leptin) remained unaltered.

Our biochemical and morphological findings suggest a different organisation of collagen fibres in tissues of patients with USI+POP, when compared with both the controls and the POP patients.