Clinical Endoscopic and Histological Characteristics of Helicobacter Pylori Positive and Negative Armenian Children with Recurrent Abdominal Pain and/or Dyspepsia

Background Recurrent abdominal pain (RAP) and dyspepsia are common complaints in children. These symptoms are often associated with Helicobacter pylori (Hp)infection. Aim of the present study was to prospectively analyze clinical, endoscopic and histological characteristics of Hp+ and Hp- children with RAP and/or dyspepsia. Methods Patients aged 2-18 years with RAP and/or dyspepsia, referred for upper endoscopy to Arabkir MC from November 2015 to December 2017, were involved in the study. Histology was assessed according to the updated Sydney system. Gastric and duodenal specimens were stained by modied Giemsa staining for Hp infection. One antral biopsy was cultured in Hp selective media. 150 patients were included into the study: 70.7% Hp+,29.3% Hp-. Nausea and vomiting were signicantly more common in Hp+ patients (p<0.05). Gastric nodularity (p=0.02), erosions in the stomach (p=0.056), and duodenal erosions (p=0.019) were more common in Hp+. Chronic active (p=0.027) and non-active gastritis (p=0.002), cumulative ndings of metaplasia/dysplasia/atrophy in the stomach (p=0.014) and chronic non-active duodenitis (p=0.016), were signicantly more common in Hp+ patients. Hp infection prevalence is high in Armenian children with dyspepsia and/or RAP. Clinical symptoms, endoscopic ndings and histopathological ndings were signicantly different in Hp+ patients as compared to Hp- patients.


Introduction
Currently Helicobacter pylori (Hp) infection is a leading cause of in ammatory and malignant diseases of the upper gastrointestinal tract [1,2,3,4].
Prevalence of Hp infection differs and depends on age, geographical, socio-economical, ethnical and other factors [1,5]. In developing countries it reaches 70%, and younger ages are more commonly affected [2,3].
Hp infection is usually acquired during the rst years of life in both developing and developed countries. In children it is mainly manifests as gastritis and duodenitis (up to 90-95%). Peptic ulcer disease (PUD) is observed approximately in 5% of children younger than 12 years and in 10% older than 12 years. Gastric malignancies associated with Hp are very rare in the paediatric age group [4,6,7,8].
Armenia is a country with high incidence of peptic ulcer of stomach and duodenum in patients older than 15 years (100.3/100.000 and 468.2/100.000 respectively in 2018). Penetrating ulcers make 4.08-4.1/100.000.
There is also high prevalence of stomach cancer in the adult population (57.7%) [9]. Although there is no data on prevalence of Hp infection among children, and limited data in adults in Armenia [10], high level of Hp infection prevalence is assumed in Armenian children.
Hp eradication therapy aims to prevent complications such as bleeding and penetrating ulcers as well as gastric malignancies. A limiting factor for the treatment success is antibiotic resistance, which differs in developed and developing countries and depends on the spectrum of antibiotic use [11].

Aim Of The Study
Aim of the present study is to prospectively analyze clinical, endoscopic and histological characteristics of Hp positive and negative Armenian children with recurrent abdominal pain and/or dyspeptic symptoms. History included information about personal details, family members suffering from GDD, gastric malignancies in the family as well as data on, main complaints, disease onset and eradication treatment before. We included data of 1st and 2nd line relatives suffering from GDD and/or gastric cancer taking into consideration peculiarities of Armenian society -common living with them All patients underwent esophagogastroduodenoscopy (EGD) under general anesthesia with 4 biopsies by Olympus GIF-XP170N and Olympus GIF-H170 endoscopes. Two biopsies were taken from the antrum (one for rapid urease test and histology, one for Hp culture), one from the duodenal bulb and one from the distal esophagus. We used the rapid urease test Helpyl (Association of Medicine and Analytics, Russian Federation, http://www.amamed.ru/index.php?i=7). Histology was assessed according to the updated Sydney system (20).

Methods
Gastric and duodenal specimens were stained by modi ed Giemsa staining for Hp infection. One of the antral biopsies was cultured in Hp selective media (ChromID, Biomerieux, France) and Columbia agar with 5% sheep blood (Biomerieux, France).
Patients were divided into 2 groups: The rst group were patients Hp + by 2 invasive tests. This group was divided in 2 subgroups: subgroup 1 were patients with ulcers, and/or erosions, and/or nodularity in the stomach or duodenum; subgroup 2 were patients with normal appearing mucosa of stomach and duodenum or only super cial changes.
Distribution of gender in the groups was: Hp + male/female 50/56 and Hp-56/24, shown in the Fig. 2, there was no statistically signi cant difference between gender concerning Hp presence (p > 0.05) Comparative analysis of number of Hp + patients from urban area (capital Yerevan and regional towns) and country side did not show any statistical difference in distribution of Hp (Fig. 3).

Clinical Data Comparison
Gastric cancer was not signi cantly more common in families of Hp + patients (F = 1), however most of the family members of Hp + group had dyspeptic symptoms and/or abdominal pain, but were not investigated (F = 0.001) ( Table 1).
The most common symptoms in both groups were recurrent epigastric pain, nausea and vomiting. Distribution of symptoms in the two groups is shown in Table 2. Nausea and vomiting were signi cantly more common in Hp + patients (p < 0.05).
When we have compared 2 subgroups in the Hp + group divided by the severity of endoscopic changes, Regurgitation and night time pain were signi cantly more common in Hp + patients with stomach and duodenal ulcerative and aphthous erosive lesions ( Table 3).
Analysis of endoscopic data has shown that gastric nodularity, erosions in the stomach, erosive lesions in the duodenum are signi cantly more common in Hp + compared to Hp-patients ( Table 4). Besides of 7 Hp+ (15.9%) patients, 2 (4.5%) of Hp-patients had ulcers in the stomach and duodenum.
The comparison of signi cant histologic changes in Hp + patients with super cial and ulcerative/erosive lesions did not show any statistical difference (Table 6) (p > 0.05).

Discussion
This is the rst study assessing clinical, endoscopic and histological characteristics of Hp + and Hp-Armenian children with recurrent abdominal pain and/or dyspepsia.
Prevalence of Hp in symptomatic children differs from country to country: 34.6% in Ethiopia (15), 25% in Hon Kong (14), 24.5% in Bulgaria (13), 64.6% in Egypt (16). The prevalence is mainly depending on socio-economic status and number of family members. There is only one study assessing seroprevalence of Hp infection in symptomatic adults with dyspeptic symptoms in Armenia showing of 49% being positive [10]. In our cohort of patients with recurrent abdominal pain and/or dyspepsia Helicobacter pylori was diagnosed in 70.6%. This high Hp negative children shown in symptomatic pediatric population [13,14,15,16]. In contrast to published studies from other countries our study showed that night time abdominal pain and regurgitaion were statistically more common in Hp + children with PUD and/or aphthous lesions in the upper GI tract.
Antral nodularity is one of the signs of Hp associated gastritis and maybe associated with higher grade of gastritis in children [ 23, 25, 26]. According to our data erosive lesions in the stomach and duodenum were statistically more common endoscopic ndings in Hp + patients, gastric nodularity were exclusively found in Hp + group.
Low incidence of ulcers in Hp positive children was reported in Chinese [17] 7.2% and European (6.8%) pediatric patients [4]. In contrast to it, in developing countries PUD prevalence in Hp positive children reaches 33.2% [18,19]. Our study showed low incidence of PUD in Hp + Armenian children, which might be explained by treatment received before admission. 2 Hp -patients had ulcers, probably due to GI bleeding or false negative Hp test.
Data obtained by Canan O. et al, showed that in two third of the patients with nonorganic dyspepsia had normal histological data, while one third had mild or chronic non-active in ammation of the mucosa [20]. Similarly in our cohort of patients the main histological ndings in Hp + patients were chronic active and non-active gastritis and duodenitis, while in Hp-patients mainly histologically normal mucosa was seen. Nevertheless more than half of Hp-negative patients had chronic non-active in ammation in the stomach.
Our study showed that serious histologic changes were exclusively seen Hp + children, and equally observed in        Distribution of patients by place of inhabitance