The Outcome of Pediatric Esophageal Strictures Managed with Endoscopic Balloon Dilation in Saudi Arabia

Introduction

Post-tracheoesophageal fistula repair (post-TEF repair) anastomotic strictures, esophageal atresia (EA), corrosive injuries (CI), gastroesophageal reflux disease, peptic esophageal strictures, epidermolysis bullosa, and achalasia ¹ cause esophageal stricture in the pediatric population. The presenting symptoms for esophageal strictures usually are dysphagia, vomiting, or drooling, which may lead to a decrease in oral intake, weight loss, and finally could lead to failure to thrive.^2–5

The management of esophageal strictures went from open surgery to endoscopic dilatation using semirigid dilators (bougienage with or without guide-wire) or endoscopic balloon dilators (EBD).

EBD is becoming an established method of treatment, especially in the last two decades.^6,7 The purpose of esophageal dilation is to manipulate the esophageal diameter increasing it to improve dysphagia symptoms achieving sufficient food intake. However, no evidence-based studies regarding the differences in efficacies and rate of complications of the two types of dilators are reported.

Moreover, intralesional steroid injections and topical application of mitomycin C are two adjuvant therapies that applied for refractory esophageal strictures as they may reduce the number of dilations and help avoid unnecessary surgical procedures. Yet, there is controversy regarding their effectiveness.^8,9

Materials and Methods

A retrospective study was conducted between 2009 and 2019 after IRB approval at four tertiary centers; King Abdulaziz University Hospital (KAUH), King Abdulaziz Medical City (KAMC), King Fahad Armed Forces Hospital (KFAFH), and King Faisal Specialist Hospital and Research Centre (KFSHRC); which are located in Jeddah, Saudi Arabia. Medical records of 137 pediatric patients with esophageal strictures were reviewed. Patients younger than 15 years of age who underwent EBD, Savary, or both were included in the study. The follow-up period was more than 24 months since last procedure. Patients with recent upper gastrointestinal surgery, active or recent perforation, severe cardiorespiratory disease, malignant disease of the esophagus, pharyngeal or cervical deformity, and patients with large thoracic aneurysms due to the risk of perforation, coagulopathy, and incomplete or missed data were excluded. Esophageal strictures were diagnosed based on clinical symptoms (dysphagia, drooling, and vomiting), barium esophagography, and/or endoscopy. The stricture level identified by barium meal was performed for all patients. Dysphagia Score is graded as 0, normal solid diet; 1, ability to swallow a semisolid diet; 2, ability to swallow a soft diet; 3, ability to swallow liquids only, and 4, complete dysphagia.^10,11 Patients with dysphagia score >2 or 2 with acute weight loss were considered for EBD therapy. Data were obtained from medical records using data collection sheets, including demographic, etiology, symptoms, treatment, and follow-up. After obtaining the consent, the parents or legal guardians were aware that in most cases, serial dilatations were needed. Gradually increasing the diameter of dilators was used with each setting. Experienced pediatric surgeons and pediatric gastroenterologists performed EBD and Savary in all centers except for KFAFH, which was done by pediatric surgeons. We started by endoscopy to evaluate the strictures. Depending on the stricture's degree and patient's age, the catheter size was chosen. The guidewire of EBD or Savary was inserted above the level of the strictures. The position of the catheter was confirmed when the waist was apparent and centered to strictures. Manual inflation usually 12 to 18 atm, as measured by pressure gauge (held for at least 60 seconds), was performed until the waist disappeared or bleeding occurs. Dilatation using the balloon catheter diameter size from 4 to 22 mm and the inflation duration from 60 to 120 seconds were selected depending on patient's age, severity of the strictures, and operator experience. The “rule of three” was used as a reference for inflations. ¹² After dilatation, the endoscope was proceeded through the strictures to assess the esophagus for any complication, evaluate the diameter after dilatation, and appreciate the length of the dilated strictures.

Achieving significant increment of weight and height (nutritional status) and improving the dysphagia symptoms are clinical parameters used to assess the effectiveness of esophageal dilatation. Baseline (before first dilation), 6 months, and 12 months' weight and height for every patient were used to assess nutritional status. z-Scores for weight-for-age and height-for-age were evaluated as nutritional parameters of outcome. The weight-for-age and height-for age z-scores were calculated using WHO Anthro Survey Analyzer. ¹³ Outcome parameters measured included the number of dilatations, nutritional status, and if symptoms had been relieved. Clinical success after treatment was defined as having <10 dilations and at least one of the following: achieving an improvement of nutritional status (weight and height or relieving of symptoms). An improvement of nutritional status was defined as achievement of an increment of weight-for-age z-score during long-term follow-up (6 and 12 months). Clinical failure after treatment was defined as necessity for dilation for more than 10 dilations. Data were entered using Google form. Differences in factors between success and failure groups were analyzed using statistical package for the social sciences (SPSS) version 21 used for statistical analysis. Continuous variables are presented as mean and standard deviation (SD), and analyzed by Student's t-test. Statistical significance considered if P is <.05.

Results

Between 2009 and 2019, data of 137 pediatric patients diagnosed with esophageal strictures were collected from 4 tertiary centers located in Jeddah-Saudi Arabia. This includes 64 males (46.7%) and 73 females (53.3%). The youngest patient was 4 days old and the oldest was 13 years old at the time of first dilation. The mean ± SD of age of patients was 34.2 ± 2.94 months. Dysphagia was the most frequent symptom on admission (n = 78, 56.9%), followed by vomiting (n = 43, 31.4%) and drooling (n = 14, 10.9%) Table 1.

The most frequent cause of esophageal strictures was post-TEF repair (n = 51, 37.2%). There was no statistical significance between the method of dilation and the cause of esophageal strictures (P = .09) Table 2. Forty-seven patients (34.3%) were from KFSHRC, while KAUH, KAMC, and KFAFH patients' numbers were 42 (30.7%), 32 (23.4%), and 16 (11.7%), respectively. The most common method of dilation performed at KFSHRC, KAMC, and KFAFH was the semirigid Savary-Gilliard bougies technique: n = 30 (50.8%), n = 18 (30.5%), and n = 11 (18.6%), respectively, while in KAUH, most of the cases were intervened using balloon dilatation, n = 40 (76.9%).

The total number of dilatation sessions in all patients was 716, where 105 (76.6%) patients underwent multiple sessions of dilation. Semirigid Savary-Gilliard bougies was the most repeated method of dilation (n = 292). When EBD method was used alone, the number of dilations needed was 238, and when both methods were used, the number of dilations needed was 186. The frequency of dilation was not statistically significant with the etiology stricture (P = .09).

During one session of dilation, the diameters of the first and last dilation obtained. The median number of dilatations that resulted in the successful outcomes is 4 dilations per patient. Adjuvant therapies used in 16 patients. Local injection of steroids (n = 5, 3.6%) and topical application of mitomycin C (n = 11, 8%) were applied for patients who underwent EBD. Yet, there was no statistical significance between the use of adjuvant therapy and the success rate (P = .134).

Overall, the success rate achieved in 109 cases was 79.6%. Among the three methods of management, success rate of cases dilated by EBD only was 90.4% (n = 47), followed by cases dilated by Savary dilation only are 74.6% (n = 44), and cases underwent both EBD and Savory dilations are 69.2% (n = 18). There is a statistical significance between the success rate parameters and the method of dilation (P = .042). However, there was no statistical significance between the success rate and the etiology of the strictures (P = .233). The highest success rate reported with dilation of middle strictures. The detailed account of dysphagia score pre- and postdilation for each method of dilation is shown in Table 3. Weight-for-age and length/height-for-age z-scores have been calculated and are illustrated in Figures 1 and 2, respectively. After 24 months of dilation, the highest improvement in weight for age z-score was found in cases of lower strictures with average increase in z = 1.948 (P = .001), followed by middle strictures with average increase in z = 1.381 (P = .028). Moreover, the highest improvement in height for age z score was found in cases of middle strictures with average increase in z-score = 2.204 (P = .016) after 24 months of dilation.

OPEN IN VIEWER

FIG. 1.

Weight-for-age z-scores curves at baseline (before dilation), 6, 12, 18, and 24 months after dilation in relationship to the stricture level (upper, middle, lower, and multiple level strictures).

OPEN IN VIEWER

FIG. 2.

Length/height-for-age z-score curve at baseline (before dilation), 6, 12, 18, and 24 months after dilation in relationship to the stricture level (upper, middle, lower, and multiple level strictures).

Three complications are reported; failure of the dilation procedure (n = 8, 5.8%), the need of surgical intervention (n = 6, 4.4%), and esophageal perforation (n = 4, 2.9%). The highest number of complications was in patients managed by Savary dilatation alone (n = 9, 15.3%), or by both procedures (n = 4, 15.4%). Less complications were reported in patients who underwent EBD alone (n = 5, 9.6%), but the difference was not statistically significant (Table 4, P = .957). The stricture etiology was not statistically significant for the reported complication (P = .763).

Discussion

Endoscopic dilation is increasingly becoming the modality of choice in treating esophageal strictures, with either semirigid dilators or endoscopic balloon dilators. In the present study, most of the patients (43%) managed with semirigid dilators alone, while 38% managed with EBD alone, and in 19% both methods were used. This depends on the availability and preference of the operators in each center.

There are several etiologies resulting in this condition; the most common in the present study was post-TEF repair followed by EA then CI. This is consistent with several studies.^1,4

The aim of our study is to evaluate the efficacy and safety of endoscopic dilation in terms of the improvement of clinical and nutritional status. The results indicate that there is a significant and satisfactory outcome with using endoscopic dilation as the method of choice. Depending on the definition of successful outcomes, our success rate is 79.6%. Many studies have reported similar results ranging from 70% to 100% success rate.^2,14–16 One of these found that esophageal dilation was successful in 87% out of 62 studied patients who were symptomatic following surgical repair of EA. ¹⁴

Our result showed superiority of EBD compared with semirigid dilators (Table 1). Several studies have mentioned similar results with a higher success for EBD.^2,3,9 One of these reported 100% success rate in 14 children who managed with EBD over 11 years. ¹⁵

The median number of dilatations that resulted in the successful outcomes is 4 dilations per patient, which is supported by several studies with a median number of 2–5 dilatations achieving the desired clinical outcome.^6,15,17

Table 3 shows that about 81.8% of patients successfully had complete relief of dysphagia and turned to Grade 0 (able to eat a solid diet). Also, we found out that the relationship between EBD, Savary dilatation, and both is statistically significant, as the P value <.001. In comparison between the EBD and Savary dilatation, we noticed that Savary achieved a high clinical success rate in pediatric patients with esophageal stricture (86.4%), while the perforation rate and the post-op complications that associated with Savary for esophageal stricture were higher, although it is statistically insignificant.

A significant improvement was observed among all methods of dilation resulting in satisfactory weight gain and nutritional status. We found that lower and middle level strictures had a statistically better outcome than upper level or multiple levels with significant rise within the nutritional status (weight for age z-scores). A similar result was reported by Chang et al. in one of the few studies referring to nutritional outcome. ¹⁰ Yet, the present study further adds a significant increase as well in height for age z-score in the middle level strictures.

No statistical significance was found between success rate and etiology or presenting symptoms. However, there was a relatively higher failure rate in CI (Table 1). This could be explained by the fibrosis, scarring, and restenosis caused by inflammatory reactions.^6,10 Moreover, CI may lead to multiple level strictures, an increase in number of dilations, and possibly high rates of complications.^1,18

The overall rate of complications in this study is 13.1%, most of which are due to semirigid dilators (Table 4). Perforation was seen in 3.4% of cases dilated with semirigid Savary dilators, compared with 1.9% of cases dilated with EBD.^1,19–22 This is most likely due to the axial shearing force exerted on the strictures by semirigid dilators rather than the radial force of EBD.^8,21 Meanwhile, our perforation rate from semirigid Savary was less than what reported in literature. ²³ In cases of refractory strictures, the analysis did not reveal a significant relationship between the use of adjuvant therapy and the success rate or the outcome. Similarly, previous studies reported no significant effects, higher complication rates, or conflicting outcomes.^6,7,9,24

The limitations of this study include being a retrospective one with differences in operator specialties, protocols, and techniques when practicing endoscopy. In addition, an issue due to the variation in follow-up standards of different centers is presented.

On the contrary, collecting data from multiple centers allowed for a larger sample size (137 patients) compared to other publications. To our knowledge, our study is the first one evaluating and comparing between the two methods of dilation in terms of outcome as well as using the adjuvant therapy for refractory cases. Furthermore, the study is one of few, if any, to assess both weight and height to evaluate the nutritional outcomes following dilation.

In conclusion, our findings suggest that, while endoscopic dilatations are safe and efficient in managing children with esophageal strictures, there is significant improvement in both clinical and nutritional outcomes. Higher success rate is seen in EBD compared with semirigid dilators, which possess higher complication rate. Therefore, we recommend EBD be performed over semirigid dilators to minimize complications. We propose that further studies needed to evaluate the clinical and nutritional outcomes in relationship with other variables such as the interval between dilatations, duration of dilatation, and other aspects of dilatation technique.