1. Introduction

Anorectal malformations (ARMs) represent a significant proportion of surgical pathologies encountered in neonates, infants, and young children. These anomalies are among the leading causes of severe congenital disability in pediatric patients, with an estimated incidence of approximately 1 in every 5,000 live births [3,10]. ARMs encompass a wide clinical spectrum, ranging from simple low-type anomalies to complex high lesions, and their effective management and treatment require a multidisciplinary approach involving not only pediatric surgeons but also neonatologists, pediatricians, gastroenterologists, and rehabilitation specialists. The surgical strategy in patients with ARMs is typically determined by the type and location of the anomaly, the presence of associated malformations, and the overall clinical condition of the child. Treatment may involve either a single-stage radical procedure or a multistage surgical approach. Currently, a variety of surgical techniques are employed for the correction of ARMs, including anoperineal, abdomino-sacral-perineal, and abdominoperineal approaches, as well as anterior sagittal anorectoplasty (ASARP) and posterior sagittal anorectoplasty (PSARP). These procedures may be performed with or without a protective colostomy [6,8].

Recent advancements in surgical technology, anesthesiology, intensive care, medical imaging, and neonatal care have substantially improved the postoperative and long-term management of anorectal malformations (ARMs). These developments have enabled not only the restoration of anatomical integrity but also the implementation of optimized strategies for bowel function management during long-term follow-up [1,2,4]. A review of the literature reveals that the functional outcomes of surgical interventions in ARMs have often been inadequately assessed - typically relying on a limited number of criteria and lacking a uniform, comprehensive methodology. The absence of standardized protocols for long-term evaluation contributes to the variability of reported outcomes and introduces a degree of subjectivity into their interpretation. Functional assessments commonly include clinical examination, anorectal manometry, radiological imaging, and various continence scoring systems such as the Kelly score, the Baylor Continence Scale (BCS), and the Krickenbeck classification [5,11]. In addition, instruments for assessing psychosocial well-being and health-related quality of life (HRQoL), such as the PedsQL questionnaire, are also employed. Despite the availability of these multidimensional tools, their application in clinical practice remains inconsistent [7,9].

1.1. Purpose of the Study

To conduct a longitudinal analysis of the impact of surgical treatment outcomes on bowel function and quality of life in children diagnosed with low-type fistulous anorectal malformations.

2. Materials and Methods

This study was based on the clinical records of infants and young children with low-type anorectal malformations (ARMs) who underwent surgical treatment at the Department of Pediatric Surgery of the Andijan Regional Multidisciplinary Medical Center between 2015 and 2024. The investigation was designed as a cross-sectional cohort study. During the study period, a total of 135 children were admitted with diagnoses of “low anorectal malformation,” “atresia ani,” or “atresia ani et recti.” Among them, non-fistulous low-type ARMs were identified in 92 cases (68.1%), while fistulous forms were diagnosed in 43 patients (31.9%). Due to changes in diagnostic and surgical management strategies over the years, the cohort was divided into two groups for comparative analysis. The retrospective group included 73 patients (54.1%) treated between 2015 and 2019, whereas the prospective group comprised 62 patients (45.9%) treated between 2020 and 2024. In line with the study objectives, only patients with fistulous low-type ARMs were included in the main analysis. From the retrospective group, 16 of the 21 patients (21.9%) with fistulous ARM types were included in the control group. Exclusions from this group included 2 cases with rectovesical fistula, 2 with rectovaginal fistula, and 2 neonates with multiple severe congenital anomalies. In the prospective group, 1 patient with a rectovesical fistula and 2 patients with life-incompatible multiple congenital anomalies were also excluded. The remaining 23 patients (37.1%) formed the study group for prospective analysis.

Accordingly, after applying the exclusion criteria, a total of 39 infants and young children with fistulous low-type anorectal malformations (ARMs) who underwent surgical treatment were included in the study.

2.1. Study Design

In the study group, anoperineal and rectoperineal fistulous ARM types were diagnosed in 8 male (34.7%) and 4 female infantss (17.4%), while in the control group, these types were observed in 6 male (37.5%) and 2 female (12.5%), respectively. The rectovestibular fistula was the most common anomaly overall: it was detected in 11 girls (42.8%) in the study group (Group A) and in 5 girls (31.2%) in the control group (Group B). Additionally, the rectoscrotal variant of ARM was diagnosed in 3 boys (18.7%) in the control group (Figure 1).

Figure 1. Study design

In accordance with the study objectives, a reference group was established in order to evaluate how closely postoperative bowel function and quality of life outcomes in the study cohorts approximated normal physiological parameters over short- and long-term periods. This reference group consisted of 20 clinically healthy children (10 boys and 10 girls) with normal bowel function who had been admitted to the urology and surgery departments of the medical center with unrelated diagnoses such as inguinal hernia, hydrocele, and cryptorchidism. The group was matched by age and sex to the study population, ensuring demographic comparability.

2.2. Surgical Management

In both the retrospective and prospective groups, depending on the specific type of low-type fistulous anorectal malformation, patients underwent either single-stage anal reimplantation procedures or staged reconstructive anorectoplasty following a protective colostomy. The types of surgical procedures performed in the study groups are presented in Table 1.

Table 1. Types of Surgical Procedures Performed in the Study Groups According to Patient Sex and Fistula Type

According to the data presented in Table 1, anoperineal surgeries were more commonly performed in both study groups, regardless of patient sex. Among the 13 total anoplasties conducted using the Stone–Benson technique (33.3%), 9 procedures (23.1%) were performed in female patients, 6 (15.4%) of whom presented with vestibular fistula-type anal atresia. In contrast, Solomon–Lenyushkin procedures for fistula closure and anal reimplantation were more frequently applied in male patients (9 out of 10, or 23.1%) across both groups, primarily for ano- and rectoperineal fistulas. It is worth noting that anal reimplantation using the Stone–Benson approach was performed in three cases as a second-stage radical procedure following a protective colostomy: one male and two female patients. The primary reasons for this staged approach included anatomical malpositioning of the initial colostomy (not aligned with the anal sphincter), recurrence of the fistula, neorectal retraction, and stenosis. For similar reasons, radical abdominoperineal surgery according to the Romualdi–Rehbein technique was performed in one male patient (2.56%) and two female patients (5.13%) in the control group with vestibular fistula.

Anterior sagittal anorectoplasty (ASARP) was performed in 3 boys (7.69%) and 2 girls (5.13%) in the study group with anoperineal fistulas, as well as in 8 girls (20.5%) with vestibular fistula-type anorectal malformation. Of these, one male (2.56%) and two females (5.13%) underwent the procedure during a second-stage operation following colostomy. The ASARP procedure, initially proposed by P. Mollard et al. in 1978 and later refined and introduced into practice by Akira Okada in 1992, was employed in this cohort using a sphincter-preserving technique. Notably, the modified ASARP technique differed from the original in the following key aspects:

- the rectal segment was not approached via longitudinal division and subsequent reconstruction of the muscle complex; instead, gentle dilation through the center of the sphincteric ring was performed to create the neorectal canal, reducing the risk of functional instability and promoting long-term continence;

- the fistulous tract was mobilized through the posterior rectal wall and closed from within, which minimized trauma to the vaginal vestibule and allowed for maximum preservation of the hymenal ring.

2.3. Measurements

Based on the primary aim of the study, bowel function and its impact on quality of life were assessed in both study groups among children with low anorectal malformations of the anoperineal and vestibular fistula types who had undergone anal reimplantation. To evaluate these outcomes, two validated instruments were employed: the Baylor Continence Scale (BCS), which measures continence and social adaptation, and the Pediatric Quality of Life Inventory (PedsQL 4.0), which assesses health-related quality of life in children [8,9].

The BCS consists of 23 questionnaire items with a total score ranging from 2 to 84 points. Lower scores indicate better continence and social adaptation. The PedsQL includes 23 items as well, covering multiple domains, including physical functioning (8 items), emotional functioning, and social functioning, enabling comprehensive assessment of a child’s quality of life. Data for both continence and quality of life scores were obtained from the parents or legal guardians of children under the age of 3, based on their responses to the respective questionnaires.

2.4. Statistical Analysis

All statistical analyses were performed using IBM SPSS Statistics Base software (version 27.0, 2020, USA) under a proprietary license. A p-value of less than 0.05 was considered the threshold for statistical significance. Categorical variables were compared using the chi-square (χ²) test. Continuous variables were presented as means and standard deviations and were analyzed using either the independent samples t-test or one-way analysis of variance (ANOVA), as appropriate. The significance of differences between study groups was determined using the Clopper–Pearson exact method based on the β-distribution to calculate 95% confidence intervals (CI) for binomial proportions. The correlation between bowel function and quality of life was assessed using Pearson’s correlation coefficient. In addition, a linear regression analysis was performed to evaluate the relationship between BCS scores and overall PedsQL outcomes.

3. Results

No significant differences were observed in age or anthropometric parameters (weight and height) between the children included in the study (p>0.05). In the control group, during the observation period, 2 infants (12.5%) were under 3 months of age and 14 children (87.5%) were between 3 and 12 months. In the study group, these values were 6 children (26.1%) under 3 months and 17 children (73.9%) between 3 and 12 months, respectively (Table 2).

Table 2. Demographic and anthropometric characteristics of patients in the study and reference groups

According to the table, although the mean age of patients in the study group was slightly lower compared to the control group (4.26±2.16 vs. 4.50±1.71 years), their mean body weight was higher (8295.6 g vs. 7950.0 g). The reference group showed a mean age of 4.33±1.94 years and mean weight and height values of 7750.0±2803.4 g and 76.0±18.5 cm, respectively, which were comparable to those observed in the study cohorts. This indicates that the representativeness of the samples was ensured.

In the reference group, the mean BCS score was 7.34±4.62, which was significantly lower than in both the control group (18.24±10.1) and the study group (11.61±4.41), confirming markedly better continence outcomes in the reference population (Figure 2).

Figure 2. Mean BCS scores and percentage distribution among children in the study groups

In addition, Figure 2 presents the percentage distribution of individual BCS scores. Nearly half of the patients (52.8%) had BCS values above 12 points. Specifically, such scores were observed in 68.1% of children in the control group, 34.5% in the study group, and only 16.2% in the reference group (p<0.001). In the control group, 4 children, and in the study group, 1 child, demonstrated BCS scores above 40 points. The main complaint among patients with higher scores was constipation. Children with BCS scores ranging from 20 to 30 reported painful defecation and occasional rectal bleeding. These patients were treated with laxatives such as lactulose and glycerin, while cleansing enemas were used only in selected cases. Chronic constipation was diagnosed in 2 patients from the control group with BCS scores between 45 and 52 points, and in 1 patient from the study group. The differences in quality of life outcomes (PedsQL scores) between the study groups are illustrated in Figure 3.

Figure 3. Comparative PedsQL Domain Scores by Type of Surgery in the Study Groups

The analysis of the lower graph, which presents percentage indicators, demonstrates that in the reference group, quality of life consistently remained above 90 points across all percentiles. In the study group, although percentage indicators were slightly lower, they showed a tendency to approximate reference values over time. In contrast, the control group exhibited markedly lower quality of life scores across all percentiles, which did not exceed 80 points even at the higher end.

When evaluating the “Physical Health” domain, the reference group showed a mean score of 92.4±3.2 (95%CI: 84.5–95.6). In the study group, this value was 91.8±3.4 (95%CI: 84.4–93.4), representing a difference of 0.6 points compared to the reference group, which was not statistically significant (p>0.05). In the control group, however, the mean physical health score was 86.2±3.1 (95%CI: 81.6–88.7), which was significantly lower than the reference by 6.2 points (p<0.001) (Table 3).

Table 3. Statistical differences in PedsQL domain scores between study groups and the reference group

When evaluating the emotional functioning domain, the reference group demonstrated a mean score of 95.4±3.0 (95%CI: 86.4–96.3). In comparison, the study group scored 93.4±3.3 (95% CI: 85.1–94.2), representing a statistically significant but clinically minor difference of 2.0 points (p<0.05). The control group, however, had a substantially lower mean score of 86.2±3.8, with a significant difference of 9.2 points compared to the reference group (p<0.001).

It is noteworthy that the social functioning domain revealed the largest discrepancies. The study group had a mean score of 87.9±3.1 (95%CI: 83.2–91.4), whereas the control group achieved only 78.6±4.0 (95%CI: 72.4–80.7). Compared with the reference group, these scores were significantly lower by 3.7 points (p<0.05) in the study group and by 13.0 points (p<0.001) in the control group, highlighting a clear deficit in social adaptation.

4. Conclusions

The findings of this study demonstrate that in children born with low anorectal malformations, single-stage surgical procedures- particularly those incorporating sphincter-preserving strategies such as anterior sagittal anorectoplasty (ASARP)-enable the maintenance of health-related quality of life at levels nearly comparable to the reference group, especially within the domains of physical health and emotional functioning. Although a slight reduction was noted in the social functioning domain, this decrease was considerably less pronounced compared to that observed following multi-stage procedures involving colostomy. In contrast, the control group exhibited significantly lower quality of life scores across all domains relative to the reference population, indicating that functional and psychosocial recovery is more limited after two-stage surgical approaches.

Furthermore, the observed inverse relationship between BCS and PedsQL scores, particularly in the domains of emotional and social functioning, reflects marked impairments in psychosocial integration and emotional stability associated with increasing bowel dysfunction. These findings emphasize the necessity of timely identification and management of defecation-related problems, as well as the importance of continuous monitoring of factors influencing quality of life, including patient age, type of surgical intervention, follow-up duration, and the presence of comorbidities.