Time trend in the surgical management of obstructed defecation syndrome: a multicenter experience on behalf of the Italian Society of Colorectal Surgery (SICCR)

Quantitative proteomics analysis reveals the pathogenesis of obstructed defecation syndrome caused by abnormal expression of dystrophin

BACKGROUND

Obstructed defecation syndrome (ODS) represents the most prevalent form of chronic constipation, affecting a diverse patient population, leading to numerous complications, and imposing a significant burden on healthcare resources. Most ODS patients have insufficient rectal propulsion, but the exact mechanism underlying the pathogenesis of ODS remains unclear.

AIM

To explore the molecular mechanism underlying the pathogenesis of ODS.

METHODS

A total of 30 pairs of rectal samples were collected from patients with ODS (ODS group) or grade IV prolapsed hemorrhoids without constipation (control group) for quantitative proteomic and bioinformatic analysis. Subsequently, 50 pairs of paraffin-embedded rectal specimens were selected for immunohistochemistry and immunofluorescence studies to validate the analysis results. Human intestinal smooth cell contractile function experiments and electrophysiological experiments were conducted to verify the physiological functions of target proteins. Cellular ultrastructure was detected using transmission electron microscopy.

RESULTS

In comparison to the control group, the expression level of dystrophin (DMD) in rectal specimens from ODS patients was markedly reduced. This finding was corroborated using immunohistochemistry and immunofluorescence techniques. The diminished expression of DMD compromised the contractile function of intestinal smooth muscle cells. At the molecular level, nucleoporin protein 153 and L-type voltage-gated calcium channel were found to be overexpressed in intestinal smooth muscle cells exhibiting downregulated DMD expression. Electrophysiological experiments confirmed an excessive influx of calcium ions into these cells. Moreover, vacuolar-like structures which may be associated with excessive calcium influx were observed in the cells by transmission electron microscopy.

CONCLUSION

Decreased DMD expression in intestinal smooth muscle may upregulate L-type voltage-gated calcium channel expression, leading to excessive calcium influx which may cause a decrease in rectal propulsion, thereby contributing to the pathogenesis of ODS.

Results of medical treatment with psyllium, lactobacillus, and tryptophan (Plurilac® Trio) in obstructive defecation syndrome

INTRODUCTION

The term "obstructive defecation syndrome" (ODS) describes a complex condition characterized by defecatory disorders. Such a condition represents a significant proportion of patients, which is estimated to be up to 30% of patients affected by chronic constipation. Presently, a broad agreement has been reached on diagnostic studies, whereas the choice of treatment that aims to improve the quality of life and/or correct the prevalent abnormalities or all anatomical abnormalities remains controversial.

METHODS

This was a retrospective cohort study on 174 patients out of a total of 232 with ODS who were observed in a specialized university unit of surgical coloproctology between 2018 and 2022. Clinical assessment included examining the values of the Agachan-Wexner constipation score and Patient Assessment of Constipation (PAC)-quality of life (QoL) scores, a full digital anorectal examination, anoscopy, RX defecography, and a urogynecological consultation; a functional anorectal test, an endoanal ultrasound, and colonoscopy were performed in select patients. The patients were reevaluated after an 8-10-week course of medical treatment based on a high-fiber diet and fluid intake and 6 g of psyllium combined with lactobacillus and tryptophan b.i.d. The results were analyzed by means of the Wilcoxon rank-sum test, comparing pretreatment scores with the results at the first follow-up visit.

RESULTS

After 8-10 weeks of conservative treatment, 128 patients declared full satisfaction, 29 reported moderate satisfaction, and 17 (9.7%) declared no improvement. Among these 17, there were 5 patients with paradoxical puborectal contractions. The value of the Agachan-Wexner constipation score after treatment decreased from the pretreatment Agachan-Wexner constipation score mean value of 23.4 ± 3.7 (mean ± SD range 15-27) to a mean value of 5.3 ± 0.7 (range 3-8, p < 0.001). The quality of life improved, as shown by the PAC-QoL score, indicating great improvement in social relationships.

CONCLUSIONS

Given the benefits of conservative therapies, they represent a cornerstone in the treatment of ODS, a complex disorder. Diet and bulking agents are mandatory forms of treatment prior to making any surgical attempt, also considering the fact that the psychosomatic component of ODS is an essential prerequisite to match patient expectations.

Laparoscopic ventral mesh rectopexy vs. transperineal mesh repair for obstructed defecation syndrome associated with rectocele: comparison of selectively distributed patients

PURPOSE

Obstructed defecation syndrome represents 50-60% of patients with symptoms of constipation. We aimed to compare the two frequently performed surgical methods, laparoscopic ventral mesh rectopexy and transperineal mesh repair, for this condition in terms of functional and surgical outcomes.

METHODS

This study is a retrospective review of 131 female patients who were diagnosed with obstructed defecation syndrome, attributed to rectocele with or without rectal intussusception, enterocele, hysterocele or cystocele, and who underwent either laparoscopic ventral mesh rectopexy or transperineal mesh repair. Patients were evaluated for surgical outcomes based on the operative time, the length of hospital stay, operative complications, using prospectively designed charts. Functional outcome was assessed by using the Initial Measurement of Patient-Reported Pelvic Floor Complaints Tool.

RESULTS

Fifty-one patients diagnosed with complex rectocele underwent laparoscopic ventral mesh rectopexy, and 80 patients diagnosed with simple rectocele underwent transperineal mesh repair. Mean age was found to be 50.35 ± 13.51 years, and mean parity 2.14 ± 1.47. Obstructed defecation symptoms significantly improved in both study groups, as measured by the Colorectal Anal Distress Inventory, Constipation Severity Instrument and Patient Assessment of Constipation-Symptoms scores. Minor postoperative complications including wound dehiscence (n = 3) and wound infection (n = 2) occurred in the transperineal mesh repair group.

CONCLUSION

Laparoscopic ventral mesh rectopexy and transperineal mesh repair are efficient and comparable techniques in terms of improvement in constipation symptoms related to obstructed defecation syndrome. A selective distribution of patients with or without multicompartmental prolapse to one of the treatment arms might be the preferred strategy.