The Impact of Probiotic Intervention on the Gut Microbiota and Bowel Function

Low Anterior Resection Syndrome Score（LARS Score）

Comparison of LARS scores among the three groups at one month postoperatively. Low Anterior Resection Syndrome (LARS) is characterized by major symptoms including difficulty defecating, urgency, incontinence of liquid stool, incontinence of flatus, and increased frequency of bowel movements. Based on severity, LARS can be classified as none (0-20 points), minor (21-29 points), or major (30-42 points) using LARS score. And higher scores mean a worse outcome.

microbial diversity

Fecal samples from study participants with ISR preoperatively and postoperatively will be collected to analyze the alpha and beta diversity of gut microbiota among the three groups

Wexner Incontinence Score

The Wexner Incontinence Score (WIS) assesses the severity of incontinence from five aspects: solid stool incontinence, liquid stool incontinence, flatus incontinence, pad usage, and lifestyle alterations. The score ranges from 0 to 20, where 0 represents normal and 20 represents complete incontinence.

Kirwan Incontinence Score

This grading system classifies anal incontinence into five grades (I-V) based on symptom severity: Grade I: No incontinence; Grade II: Incontinence to flatus or liquid stool; Grade III: Occasional solid stool incontinence; Grade IV: Frequent solid stool incontinence; Grade V: Requires a stoma (fecal diversion). Among these, Grades I-II indicate good continence function, while Grades III-IV indicate poor continence function.

Exploratory LARS Scoring Instrument

An exploratory scoring instrument was used to determine the severity of 16 specific variables that were identified by the Delphi consensus for defining LARS. In accordance with the response range defined by the WIS, there were 5 frequency options ranging from never (meaning no episodes; score 0) to always (meaning 1 or more episodes/day; score 4) for each item. Given that social and psychological features (marital separation, divorce, widowed seniors, etc) may have an influence on "relationships and intimacy," its response category for "never" was replaced with dichotomous options of "none" and "N/A." The summary score, also called the Delphi consensus severity score, was used as an index for patient-reported severity of LARS, ranging from 0 (best) to 64 (worst).

Fecal Incontinence Quality of Life (FIQL) Scale

The Fecal Incontinence Quality-of-Life (FIQL) Scale was used to analyze CSQoL. The FIQL entails 29 items that cover 4 domains: lifestyle (10 items), coping/behavior (9 items), depression/self-perception (7 items), and embarrassment (3 items).19 Each item has a range of 1 to 4 (except 2 items in depression/self-perception with ranges of 1-5 and 1-6). The score for each domain is the average of all items within its domain, and the global score is the mean of all domains. Higher scores indicate better CSQoL.