Bezoar types in children and etiological factors affecting bezoar formation


 Background

Bezoar is formed as a result of the accumulation of undigested food or foreign substances in the gastrointestinal tract (GIS). The present study aims to investigate the bezoar types seen in children and the etiological factors involved in bezoar formation.
Methods

A total of 16 patients who underwent an endoscopy and/or surgical treatment for bezoar at Harran University, Faculty of Medicine Pediatric Surgery Clinic between 2011 and 2019 were included in the study. The demographic information, laboratory and radiological findings were obtained from the patients’ file records
Results

A total of 10 patients (62.5%) were female with a mean age of 7.8 ± 4.9 years. Phytobezoars were detected in 10 patients, trichobezoars in 2 patients, lactobezoar in 1 patient, and other types in 3 patients. The etiological factors were determined to be congenital GIS anomaly in 6 (37.5%) patients; trichotillomania in 2 (12.5%) patients; mental retardation in 2 (12.5%) patients; ingestion of a foreign body during infancy in 2 (12.5%) patients; high intake of high-fiber fruit in 3 (18.5%) patients; and postoperative dysmotility in 2 (12.5%) patients.
Conclusions

Congenital GIS anomalies are mostly responsible for bezoar etiology in children and phytobezoar is the most common type of bezoar.


Background
Bezoar is the accumulation and formation of a mass of substances, such as food, medicines, and hair in the gastrointestinal tract, which are taken orally and cannot be digested [1]. 4 primary types of bezoars have been identi ed according to their contents. Bezoars containing plant materials such as vegetable and fruit bers, shells and seeds are called phytobezoars; those, whose main component is hair, are called trichobezoar; those, whose main component is medicines, are called pharmacobezoars; and those, whose main component is milk proteins, are called lactobezoars [2]. In addition, partially digested or undigested substances (e.g. chewing gum, plastic, sponge, paper, etc.) that do not fall into these four categories, are accompanied by gastric mucus and can also cause bezoar formation are called other types of bezoars [3]. Bezoars can occur anywhere in the GIS, but are most common in the stomach [4].
The development of bezoar is common especially in psychiatric disorders such as trichotillomania and trichophagia, and in children with a history of mental retardation and pica [5].
In the literature, there are single case reports about bezoars seen in childhood or small case series describing several patients [6]. No light could be shed on the etiological factors leading to bezoar formation, especially in childhood. In this retrospective cross-sectional multicenter study, the aim was to investigate bezoar types and the etiological factors involved in bezoar formation in patients undergoing endoscopy and/or surgery due to presence of bezoars in childhood.

Methods
Patients, who underwent an endoscopy and/or surgical treatment for bezoar between 2011 and 2019 at Harran University, Medical Faculty Pediatric Surgery Clinic, were included in this cross-sectional retrospective study. Patients, who recovered as a result of medical treatment, were not included in the study. A total of 16 patients were included in the study. To determine the types of bezoars and etiological factors involved in bezoar formation, patient demographic information such as gender and age, and medical information such as admission symptoms, comorbidities, treatments, bezoar type, bezoar locations, and prognoses were obtained from patients' le records.
The extracted bezoars were examined macroscopically and microscopically. Tests were performed with chloroform in cases of suspected animal hair such as wool and felt. The study was carried out with the

Statistical Analysis
The Statistical Package for the Social Sciences (SPSS) 22.0 (IBM Corporation, Armonk, New York, United States) program was used in the analysis of the data. Categorical data were expressed using n (number) and percentage (%).

Results
A total of 16 patients, 10 (62.5%) females and 6 (37.5%) males, were included in the study. The mean age of the patients was 7.7 ± 4.9 years. Of the patients, 13 (81.3%) received surgical treatment and 3 (18.7%) were treated with endoscopy. Bezoars were removed by surgical treatment after 3 patients were determined through endoscopy to have duodenal web and 1 to have duodenal stenosis, and the anomalies corrected. Bezoar were detected in the stomach in 4 patients, in the stomach and duodenum in 5 patients, in the duodenum in 2 patients, and in the ileum in 5 patients.
With respect to the type of bezoar found, phytobezoars were detected in 10 patients, trichobezoars in 2 patients, lactobezoar in 1 patient, and other types of bezoars (chewing gum, play dough and plastic material) in 3 patients. In cases of phytobezoar, the main component of the mass was found to be walnut in 1 patient, hazelnut in 1, seeded grape in 1, and kaki persimmon in 2 patients. Other phytobezoars contained many vegetative ingredients.
The etiological factors responsible for bezoar formation were congenital GIS anomaly in 6 (37.5%) patients (3 duodenal web, 1 duodenal hyper xation, 1 annular pancreas, and 1 Meckel's diverticulum), trichotillomania in 2 (12.5%) patients, mental retardation in 2 (12.5%) patients, the ingestion of foreign matter due to an inability to distinguish between nutrients and non-nutrients in 2 (12.5%) patients as a result of age, a high intake of high ber vegetable matter over a short period in 3 (18.5%) patients (persimmon in 2 patients and hazelnut in 1 patient), and a high intake of brous plant nutrients during a period of intestinal dysmotility after appendectomy in 2 (12.5%) patients (Fig. 1). In one patient, 2 etiological factors (trichotillomania and duodenal hyper xation) were detected at the same time. One of the patients with duodenal web had previously received medical treatment for bezoar and had once been treated with endoscopy. All patients with congenital anomaly were under the age of six, except for the patient with Meckel's diverticulum. Phytobezoar was detected in 4, lactobezoar in 1, and trichobezoar in 1 of these patients.
It was found that the formation of bezoar did not recur, and no complications developed during the 1-year follow-up period of the patients. The demographic and clinical features of the patients are summarized in Table 1.

Discussion
In this eight-year cross-sectional retrospective study, it was shown that phytobezoars are most common in children, congenital GIS anomalies play the most important role in the etiology, and that these anomalies mostly cause bezoar formation in early childhood. A series of 7 cases in 10 years was reported by Castle et al. [7], and a series of 4 cases in 18 years was reported by Gorter et al. [8] in the literature.
In studies conducted in adult patient groups, it was reported that bezoar formation may develop in any region of the GIS, but mostly in the stomach [9]. As far as we know, the region of the GIS in which bezoar formation occurs most in childhood has not been reported in any study in the literature to date. In the present study, it was found that in more than half of the cases, bezoar developed in the stomach or stomach and duodenum region.
In studies conducted, it has been reported that phytobezoar is the most common type of bezoar [10]. Similar to studies in the literature, vegetable nutrients were detected in approximately two-thirds of patients in the present study. It has been reported that among vegetable nutrients, persimmon is the most common cause of the formation of phytobezoars [11]. In this study, as in other studies in the literature, it was determined that the vegetable nutrients shown as the sole etiological factor for phytobezoar formation were persimmon and hazelnut.
Many studies have reported numerous etiological factors for bezoar formation, such as mental retardation, trichotillomania, GIS surgeries, a high intake of high ber vegetable matter over a short period, and raw vegetable nutrient intake. It has been reported that gastric surgeries are the most common etiological factor for bezoar formation in adult patient groups [10]. As far as we know, there are not enough data in the literature about the frequency of risk factors in childhood. In the present study, it was shown that congenital GIS anomalies, especially duodenal anomalies, were in the etiology of bezoar formation, with a rate of 37.5%.
In the literature, a case of bezoar was reported by Chien et al. due to duodenal web in a 2-year-old patient, who was previously healthy [12]. In the present study, the oldest of the 3 patients with duodenal web was 3.5 years old. While 2 of these patients had no prior history of duodenal obstruction, 1 had received medical treatment and endoscopy for bezoar. Of the patients in this group, 2 had phytobezoars and 1 had lactobezoars. In addition, the patient with duodenal hyper xation had trichotillomania, and trichobezoar was also detected. In the literature, Meckel's diverticulum accompanying bezoar was reported in several cases during childhood and it was reported that it was mostly of the phytobezoar type. One of them was Meckel's diverticulitis, accompanied by phytobezoar in a 12-year-old patient reported by Gasparella et al. [13]. Similarly, in the present study, phytobezoar presented at the Meckel's diverticulum in one case and also accompanied Meckel's diverticulitis. In the literature, 2 cases of annular pancreas, which were responsible for bezoar formation, were reported, with one of them reported by Kestel et al. in an adult patient, who had recurrent pancreatitis due to bezoar [14]. In the present study, the patient in whom the annular pancreas was detected was 2 years old and had had no previous complaints.
It has been reported that trichobezoars are mostly seen in patients with psychiatric disorders, especially trichotillomania and depression, and 14% of these patients were under 7 years of age [15]. Similar to the studies in the literature, 2 patients with trichobezoar were also diagnosed with trichotillomania in this study. One of these patients had accompanying duodenal hyper xation anomaly and was under 7 years of age.
In many studies in the literature, it has been reported that patients with mental retardation can ingest many non-nutrients, especially hair, and bezoar forms as a result [16]. In 1 of 2 patients with mental retardation, bezoar occurred as a result of their ingesting plastic material, while phytobezoar was detected in the other. Similarly, of the 2 patients, who were too young to properly distinguish between nutrients and non-nutrients, one had bezoar due to their ingesting chewing gum and the other had bezoar due to their ingesting play-dough.
It has been reported that excessive consumption of high-ber vegetable foods may cause phytobezoar formation, particularly if immature fruits or vegetables are swallowed in large quantities without su cient mastication, as they pose a risk for bezoar formation. In particular, immature kaki persimmons in this group of vegetable foods cause phytobezoar formation [17]. In the present study, similar to the literature, phytobezoars occurred in 2 cases without any risk factors after the intake of a large amount of persimmon over a short period. Similarly, in one case, phytobezoars occurred after the intake of a large amount of hazelnuts in a short time.
Bezoars have been reported to occur in conditions such as intestinal diverticulum, neoplasm, and as a result of surgical procedures, which reduce intestinal motility [16]. In this study, as noted in the literature, phytobezoars occurred in 2 cases where patients did not follow their prescribed diets after appendicitis surgery and consumed excessive amounts of high-ber vegetable matter.
In this study, the aim was to draw attention to bezoar types seen in childhood and the risk factors that play a role in bezoar formation. However, the small number of cases is a limitation of this study. It is thought that large-scale studies are needed on this subject.

Conclusion
In the present study, bezoar types seen in childhood and the etiological factors involved in bezoar formation were evaluated. Phytobezoars were shown to be the most common bezoar type, and congenital GIS anomalies to be the most common etiological factor. It was found that congenital GIS anomalies mostly occurred in the duodenal region and were seen with recurrent phytobezoar or lactobezoar formation, especially in early childhood. Congenital GIS anomalies must be kept in mind in bezoar formations, for which the risk factors in childhood cannot be explained. The reconstructive surgical interventions for these anomalies should be synchronized with the extraction of bezoar masses. In this way, it is believed that recurrence of bezoar formations and complications that may arise due to congenital GIS anomalies can be prevented.
MED prepared in conceptualizing the study and drafting introduction, methods and discussion sections of the manuscript. TG maintained the feedback on study design and provided critical feedback on earlier drafts of the manuscript and prepared Figures. SS analyzed the data, played the major role in drafting the results section and gave oversight for data collection. MC assisted with data preparation and provided critical feedback on earlier drafts of introduction and discussion. All authors read and approved the nal manuscript. Distribution of the factors that contribute to bezoar formation. GIS: Gastrointestinal system. Preschoolers group: foreign body ingestion in patients, who were too young to distinguish between food and nonnutrients