This study aimed to identify the bowel function and middle-term QOL of patients with low-type ARM, which is traditionally considered a benign abnormality [8]. Although the outcomes of low-type ARM are generally favorable [4], some patients still present with poor outcomes. This study provides contemporary data about middle-term functional and QOL outcomes in children with low-type ARM. Moreover, according to a dropout analysis, responders and non-responders had equal age and sex distribution and disease characteristics; thus, a significant selection bias is unlikely to occur.
The validated BCS tool was used to assess bowel function, and it can differentiate between normal children and those with various comorbidities. Lower scores indicate better social continence. Normal children without anatomic or functional continence problems had a mean BCS score of 11.5 [9], whereas all our patients with low-type ARM had a mean score of 17.7. Constipation was the most common early functional problem (40%) in patients with low-type anomalies [10]. When the malformation is lower, the incidence of severe constipation is higher, leading to overflow pseudo-incontinence [11]. Peña has described various degrees of postoperative constipation in 70% of patients with VF and in 50% of patients with low-type ARM [12]. These findings have their roots in the pathogenesis of ARM. First, Holsehneider and other scholars have recently pointed out that disturbances in rectal end innervation caused by surgery might lead to a high incidence of constipation [13]. Second, in 2007, Senel et al. [14] have hypothesized that constipation may be correlated to rectoanal inhibitory reflex. Abnormal colonic motility was also found in patients with ARM. Most patients with ARM present with disturbance in sophisticated bowel motility mechanism [15]. In fact, constipation is the main cause of fecal soiling, and once constipation is treated, continence and defecation pattern return to normal. In our cases, early treatment for postoperative constipation is non-standard. Some patients are treated with glycerine enema, and in some cases, traditional Chinese medicine is prescribed. Few children were treated according to the international constipation treatment protocol. Among our patients, five had a low Baylor score, of which one experienced soiling from long-term constipation. Four patients had normal spinal cord (no tethered cord) that can affect bowel control; thus, we believe that bowel dysfunction is attributed to iatrogenic causes in these patients. Among them, two had anus located outside of the sphincter. The surgeons might have performed the cutback procedure instead of the correct procedure (as shown in Fig. b). The other two patients underwent PSARP and the pull-through procedure for secondary megacolon. We believe redo operations, damage in the sphincter, mislocated anus, and incorrect treatment of constipation are the causes of fecal incontinence. In patients with fecal incontinence, the bowel management program is usually initiated [16]. Patients who require BMP therapy will visit the clinic daily for the whole week. Each patient is provided with enema, and home therapy is then performed daily. In three patients with confirmed fecal incontinence, the Malone procedure was conducted. However, only few parents provided consent for such procedure as most of them believe that their children can have normal bowel control as they get older.
The mean BCS score was higher in patients with VF than in those with PF, indicating that the bowel function of patients with PF was better than that of patients with VF. Intergroup differences can be explained by three facts. First, innervation may be involved; thus, all patients with VF (100%) and > 70% of patients with PF showed varying degrees of innervation abnormalities [17]. Second, in PF cases, the anal canal is usually located at least partially inside the voluntary sphincter funnel and is consequently managed surgically using less invasive approaches than PSARP. Therefore, in VF cases, the bowel terminates completely outside the sphincter. Third, this may be associated with the choice of procedure; that is, we prefer the PSARP procedure for patients with VF as some studies have shown that it is the main cause of constipation in ARM [18, 19]. However, this result remains controversial. In our VF cases, we performed minimal PSARP procedure without a protective colostomy, whereas some surgeons perform anterior sagittal anorectoplasty without colostomy. However, in this study, the number of patients is not sufficient to perform comparison and analysis, and we cannot conclude whether the PSARP procedure will cause constipation in our patients. In our PF cases, the treatment approach has involved individualized, minimally invasive perineal procedures that achieve satisfactory stool passage. The cutback procedure is preferred if the anus is surrounded by the sphincter. However, the key point is that the rectum should be exactly at the center of the anal sphincter.
QOL has been an important endpoint in the medical care of patients with ARM who have psychological, behavioral, or developmental problems and who experience significantly lower QOL than children without such problems. Poor outcomes have been correlated to neurological damage and mental retardation [20] or insufficient long-term follow-up and care of patients [21, 22]. In our study, a clinically relevant impairment in QOL was observed based on child self-reported total scores, particularly emotional and social score. Most likely, at least some duration of bowel dysfunction will make them feel different from their peers, causing difficulty in feeling like a part of the crowd. The fact that impairment in QOL is mostly in the psychosocial domain is not surprising. However, the QOL of the affected group was not significant differently from that of the control group. Two reasons are associated with this phenomenon. First, the participants in the ARM and normal groups were recruited from different areas. Since employment, income, education, and healthcare levels differ among regions and locations, these family differences may impact individual QOL. Second, although patients present with congenital malformations that can cause fecal incontinence, often having irreversible consequences, the participants (or their parents) in this study had positive perceptions of their QOL since their bowel control was significantly better than expected at the beginning. A previous report has shown similar results [23]. In addition, the low-type ARM is often a part of a malformation complex [24, 25]. The associated anomalies can significantly impact the QOL of patients. Cardiac (15–40%) and genitourinary malformations, including vesicoureteral reflux (15–30%), are most commonly observed [25, 26]. In our study, 23.3 and 15.4% of patients with PF and VF, respectively, presented with circulatory and urinary problems or other comorbidities.
Moreover, this study showed that functional scores were significantly correlated to QOL in emotional, social, and school areas. More severe functional situations resulted in a lower QOL. Bad bowel function, particularly fecal incontinence, is highly correlated to QOL. Most adult patients with ARM had no social problems in occupational or student life if they gained good bowel control. Grano has investigated how fecal incontinence may influence the different aspects of QOL in children and adolescents with ARMs [27]. In our study, only few patients presented with poor bowel control but have high QOL. This finding was not surprising as families were more likely to support children receiving medical therapy or psychological interventions are provided. Thus, as a higher QOL is not correlated to bowel function, we assessed the children in this study at an earlier age and found that patients with comorbidities originally had low expectations, and problems with fecal incontinence may have been balanced by strong family and social support systems.
The present study had some limitations. In this single children’s medical center in South China, 398 low-type ARM cases were recorded between 2010 and 2013. However, only 21.5% of the patients with VF and 26.7% with PF were included, thereby indicating that > 70% of the affected patients could not be contacted. This may be caused by discrepancies in the postoperative follow-up system, and the charts of the patients cannot be changed to include patient contact information. However, if the patients visit surgeons regularly, their chart can be updated any time. Unfortunately, the situations may not always be ideal, and most of our patients’ parents consider poor bowel control a normal outcome, which does not require any special care. Thus, they were more likely not to visit their surgeons for follow-up after constructive surgery. A higher non-response rate may indicate that the data in this study cannot accurately convey treatment prognosis. In addition, as children grow older, their long-term bowel function and QOL must be evaluated. In future studies, the use of a matched healthy sample from a local population would be optimal for a more direct comparison between the ARM study population and healthy controls.