Fecal Evacuation Disorder Among Patients With Solitary Rectal Ulcer Syndrome: A Case-control Study

BACKGROUND/AIMS: Data on frequency of fecal evacuation disorder (FED) among patients with solitary rectal ulcer syndrome (SRUS), hitherto an enigmatic condition, are scanty. Moreover, most such studies had limitations due to small sample size and lack of inclusion of healthy controls (HC). METHODS: Forty patients with SRUS underwent symptom assessments, sigmoidoscopy, anorectal manometry, defecography, balloon expulsion test (BET); endoscopic ultrasound (EUS) of anal sphincter complex was performed in a subgroup. Physiological tests (anorectal manometry and BET) were also performed in 19 HC. RESULTS: Patients with SRUS (26/40 male, age 37 [18–80] years) more often had FED than HC (10/19 male, age 43 [25–72] years) as shown by weight needed to expel the balloon (300 [0–700] g vs. 100 [0–400] g; P = 0.006), a trend towards abnormal BET (need of > 200 g weight for expulsion) (21/40 [53%] vs. 5/19 [26%], P = 0.058) and impaired anal relaxation (14/40 [35%] vs 2/19 [10.5%]; P = 0.048). Using Rome III criteria, most patients with SRUS reported having chronic constipation (36/40 [90%]) in spite of having normal (Bristol stool type IV, 21/40 [53%]) and diarrheal (types V, VI, VII, 6/40 [20%]) stool forms (Asian classification). SRUS patients more often (17/40 [43%]) had functional defecation disorder (Rome III criteria). Patients with SRUS with abnormal BET had thicker internal anal sphincter than those without (3.9 [3.4–7.0] mm vs 2.8 [2.0–4.0] mm; P = 0.01). CONCLUSIONS: FED was commoner among patients with SRUS as evidenced by abnormal BET and sphincter relaxation. Those with abnormal BET had thicker internal sphincter on EUS than those without.