Patient characteristics of children with peptic ulcers
Totally 255 (15%) children out of 1694 patients who had undergone upper endoscopy for investigation of upper gastrointestinal symptoms, during the study period, were identified to have gastric or duodenal ulcers, on endoscopy, among whom one patient with anastomosis site ulcer was excluded from the study. These 255 children included 157 boys and 98 girls, with a mean age of 10.0 ± 5.1 years (range; 1 day ~ 18.0 years).
Of the 255 pediatric patients with peptic ulcers, 159 (62.4%) and 69 (27.1%) patients had only duodenal ulcers and gastric ulcers, respectively. Both gastric and duodenal ulcers were observed in 27 (10.6%) patients and multiple ulcers were observed in 73 (28.6%) patients, on endoscopy.
Regarding the etiology of peptic ulcers, H. pylori infection was diagnosed in 51 (20.0%) of the 255 patients; history of preceding gastrotoxic drugs intake in 18 (7.1%); systemic diseases such as Crohn’s disease and HSP in 23 (9.0%); EoGE-related peptic ulcers in 19 (7.5%); and idiopathic peptic ulcers in 144 (56.4%) patients (Table 1). EoGE ulcers accounted for 10.2 % of 186 HNGN-PU in pediatric patients.
Changes in the diagnosis of causes of peptic ulcers in children during the study period
Fig. 1 reveals the distribution of the etiology of peptic ulcers in children during the study period from 2003 to 2017. Since the introduction of a new protocol for histopathologic evaluation of endoscopic biopsy to count tissue eosinophils in all specimens in 2011, the distribution of causes of HNGN-PU changed and EoGE newly emerged as a cause of peptic ulcers in children (Fig.1).
Comparison of clinical and laboratory factors among the 5 groups according to the etiology of peptic ulcers in children
Regarding clinical factors related to peptic ulcers in children, age at diagnosis (p < 0.001), history of atopic dermatitis (p = 0.002), and ulcer recurrence (p = 0.016) were significantly different among the 5 peptic ulcer groups (Table 1). When applying the post-test analysis between the two groups, statistically significant differences were found between the H. pylori infection group and the idiopathic peptic ulcer group at the significance level of 0.005 [Supplement 1]. Idiopathic peptic ulcer group showed statistically significant differences in atopic dermatitis history, duodenal ulcer, and peripheral eosinophilia compared to H. pylori infection group.
Regarding laboratory factors, WBC counts (p = 0.008), eosinophil counts in blood (p = 0.013), platelet counts (p < 0.001), serum levels of albumin (p = 0.027), iron (p < 0.001), ESR (p < 0.001), and hsCRP (p = 0.016) differed significantly among the 5 ulcer groups (Table 2).
Comparison of endoscopic and histopathologic findings among the 5 groups according to the etiology of peptic ulcers in children
Regarding endoscopic findings, gastric ulcers (p = 0.005), duodenal ulcers (p < 0.001), multiple ulcers (p = 0.023), and gastric mucosal nodularity (p < 0.001) differed significantly among the 5 peptic ulcer groups (Table 1). Gastric ulcers were most frequently observed on upper endoscopy in the gastrotoxic drug group (61.1%), followed by the idiopathic ulcer group (29.2%) (Table 1). Duodenal ulcers were most frequently noted in the EoGE group (78.9%), followed by the H. pylori group (66.7%) and the systemic disease group (65.2%) (Table 1). According to the results of the post-test for duodenal ulcer, there was a statistically significant difference between the H. pylori infection group and the idiopathic peptic ulcer group at the significance level of 0.005 [Supplement 1]. Gastric mucosa nodularity was most frequently noted in the H. pylori group (52.9%), followed by the EoGE group (26.3%) (Table 1).
Regarding histopathologic findings of upper gastrointestinal tracts, tissue eosinophil counts were significantly different in the esophagus, stomach, and duodenum among the 5 ulcer groups (all p < 0.001) (Table 1).
Comparison of EoGE ulcers with non-EoGE ulcers
When clinical features of EoGE ulcers were compared with those of the other groups, the patients with EoGE ulcers were significantly older in age (median 13.6 yrs. vs. 10.2 years, p = 0.022) and revealed higher rates of ulcer recurrence (21.1% in EoGE group vs. 4.7% in non-EoGE group, p = 0.018), and atopic dermatitis history (26.3% in EoGE group vs. 2.1% in non-EoGE group, p = 0.001) (Table 3).
When comparing the laboratory, endoscopic, and histopathologic findings of the EoGE group and the non-EoGE ulcer groups, only blood eosinophil counts and tissue eosinophil counts of the esophagus, stomach, and duodenum were significantly higher in the EoGE group (p = 0.001 & p <0.001, respectively) (Supplemental Digital Content 1 & Table 3).