1. Introduction
Since its discovery in 1981 by Barry Marshall and Robin Warren, Helicobacter pylori (Hp) established itself as a bacterium of major importance in the genesis of pathologies in gastroenterology [1]. The links between chronic gastritis (CG) due to Hp, peptic ulcers (PU) and some gastric cancers (adenocarcinomas and MALT gastric lymphomas) are well established [2]. Its global prevalence is in the order of 50%, predominant in Africa, Asia, Central and South America [1]. In developing countries, it affects about 80% of the population with transmission occurring very early in childhood [3]. The factors that influence the incidence and prevalence of Hp infection are age, gender, geographic and socio-economic factors [1] [3]. Among the diagnostic methods of Hp, the pathological examination of gastric biopsies performed during digestive endoscopy is most commonly used because of its high specificity and sensitivity that are greater than 90% [4]. Despite the improvement in living standards and the introduction of new Hp eradication protocols, the prevalence of this bacterium and its involvement in the genesis of gastric lesions remain a concern as well in Africa, in Asia and in the low-prevalence countries [5] [6]. In Côte d’Ivoire, few studies exist on the relationship between Hp and gastric lesions since the advent of quadruple therapy [7]. The purpose of this study is to determine the prevalence of Hp infection and to identify the determinants of infection as well as the gastroduodenal histopathological lesions associated with this infection.
2. Methods
This was a retrospective study covering the period from 1 August 2015 to 31 December 2020. Our study was carried out on the basis of digestive endoscopy reports from 3 digestive endoscopy centres in Bouaké (Bouaké Teaching Hospital, Holy Fraternity Clinic and Notre Dame des Apôtres Clinic). The study population consisted of patients who performed upper digestive endoscopy during the study period in one of the 3 centres.
We included in the study, patients in whom gastric biopsies (fundal and antral) had been performed and with pathological result from the available biopsies. For patients who performed multiple upper digestive endoscopies, only the results of the initial endoscopy and histological examination were considered for the study. On the upper gastrointestinal endoscopy reports, we collected data on age, gender, occupation, examination indications, description of gastric and duodenal lesions. The histological gastric lesions in accordance with Sydney’s categorization criteria (chronic gastritis, active gastritis, glandular atrophy, intestinal metaplasia, dysplasia and gastric cancer) and the presence or absence of Hp were also collected from the histological report of the gastric biopsies.
Epi info 7 software was used for data entry and analysis. Differences in the distribution of variables were evaluated by the Chi-square test and those with a p-value of <0.05 were considered statistically significant. Odds ratios (OR) and respective 95% confidence intervals (95% CI) were calculated for each gastric cancer precursor lesion in relation to the presence of H. pylori infection.
Ethics
The study was carried out with the approval of the Scientific Medical Director of the Bouaké’s Teaching Hospital. Confidentiality was respected by assigning an anonymity number to each investigation report.
3. Results
A total of 510 patients who met the criteria were considered in our study. The average age was 51.40 years with extremes ranging from 13 to 89 years, divided into age groups of less than 30 years (8.43%), 30 to 50 years (40.20%), 51 to 70 years (42.75%) and 71 to 90 years (8.63%). The majority of patients included were male at 59% (sex ratio 1.44). The 510 patients resided in 70% urban areas and 30% in rural areas. More than half of the patients were unemployed (25.10%) and in the informal sector (26.85%).
The overall prevalence of Hp infection was 66.47% (339/510). There was no significant difference between men (199/301) and women (140/209) for Hp prevalence (p = 0.84). There was no significant difference between Hp (+) and Hp (−) patients for different age groups (p = 0.48), gender (male/female, p = 0.84) and area of residence (Urban/rural, p = 0.19) (Table 1).
The most common indication of gastroscopy was epigastralgia (75.8%) with no significant difference between Hp (+) and (−) patients (Table 2).
The most common endoscopic lesions were gastric erythema (65.10%) and gastric ulcers (29.60%) with no significant difference between positive and negative Hp patients. A significant difference was observed only for duodenal ulcers (Table 3).
![]()
Table 1. Distribution of age, gender, place of residence and hospitalization according toH. pylori status.
![]()
Table 2. Distribution of indications for upper gastrointestinal endoscopy in 510 patients according to the presence of Hp.
![]()
Table 3. Distribution of endoscopic lesions according to the presence of Hp.
For histological lesions: Chronic and active gastritis were strongly related to the presence of Hp (respectively OR = 77.79 [30 - 187]; p = 0.001 and 260 [106 - 640]; p = 0.001). Gastric malignancies, on the other hand, were significantly related to the absence of Hp (OR = 0.19 [0.1 - 0.35]; p = 0.001). Intestinal metaplasia and gastric atrophy were not significantly associated with the presence of Hp (Table 4). These precursor lesions of gastric cancer (intestinal metaplasia and glandular atrophy) were, on the other hand, significantly related to chronic gastric univariate analysis with p = 0.02 and p = 0.001 respectively (Table 5).
4. Discussion
The results of this work show a high frequency of Hp infection in our study population. In developing countries, Hp infections affect about 80% of the population with transmission occurring very early in childhood [1] [3].
In this study, the higher prevalence of Hp in men at 58.70% compared to 41.30% in women was not statistically significant. Amel and al [8] reported that it is generally accepted that men and women have the same risk of being infected at any age confirming the results of our series. However, Houria and al reported that women are the most infected with Hp compared to men [9]. Also other studies found male predominance [10] [11] [12] [13].
![]()
Table 4. Distribution of patients by gastric histological lesions associated with the presence of Hp.
OR: odds ratio; CI: 95% confidence interval.
![]()
Table 5. Association of gastric precancerous lesions and chronic gastritis.
OR: odds ratio; IC: Confidence interval 95%.
Regarding age, our results are similar to a study conducted in Côte d’Ivoire, where no significant differences in age were reported [14]. He argues that in Africa, every adult, regardless of socio-economic status, had a childhood in an environment conducive to contamination [9].
Some studies confirm the association between Hp and urban poverty related to hygiene conditions [15]. In our study, place of residence and occupation did not significantly influence the presence of Hp. Our results correspond to the work of Andoulo et al. [16].
Epigastralgia accounted for about two-thirds of the indications of positive Hp patients. However, there is no link between this indication and the presence of Hp in our study (p = 0.35). A significant difference was observed only for weight loss between positive and negative Hp patients (p = 0.03). This difference could be explained by stenosis syndrome, which is usually responsible for weight loss in gastric tumors. The link between gastric adenocarcinoma and Hp is well established according to the literature [17].
Although the prevalence of Hp in gastric ulcers is high (68.87%). There is no significant link in our study between gastric ulcer and Hp. The link between duodenal ulcers and Hp is well established according to the literature [18]. However, it should be noted that our study was retrospective. Patients taking proton pump inhibitors or antibiotics may have false-negative histological results for Hp. Which could probably explain our results.
Hp infection is the most important risk factor for chronic gastritis, gastric atrophy and intestinal metaplasia and is considered the precursor to gastric cancer [19]. In our work, chronic gastritis and active gastritis were significantly higher in Hp (+) patients and were a risk factor with an OR of 77.79 and 260 respectively in accordance with the literature data [12]. The frequencies of atrophic gastritis and intestinal metaplasia are low in our study. The studies carried out in sub-Saharan Africa also noted a low frequency of intestinal metaplasia of less than 20%. However, they showed a higher frequency of gastric atrophy of up to 75% [5] [7]. In his review of the literature, Archampong noted that precancerous lesions (gastric atrophy and intestinal metaplasia) are not uncommon in symptomatic patients undergoing endoscopy in tertiary health facilities in Africa. Most hospital-based endoscopic studies showed prevalence rates of gastric atrophy of 5% - 38% and for intestinal metaplasia of 4% - 32% among populations in sub-Saharan Africa [20]. The presence of Hp was not significantly associated with gastric atrophy and intestinal metaplasia in our study. These gastric histological lesions are considered by several authors to be significantly related to the presence of Hp [21] [22]. Inflammation and atrophy of the gastric mucosa are known to be factors that are not conducive to the development of Hp [20]. In addition, the lack of information in our study on the use of pump inhibitors or antibiotics could influence the search for hp during pathological examination [3] [20]. The absence of link between these gastric precancerous lesions and the presence of Hp in our study could therefore be explained by these two conditions. For tumours, Hp was shown to be a determining factor in the etiology of gastric cancers [17]. In our work, tumour lesions are significantly associated with Hp with a predominance of tumour lesions in case of Hp negative. Some authors would explain this result by “the African sub-Saharan enigma”, because of an ancient early childhood infection in sub-Saharan Africans, the human and host response to Hp could be protective against a virulent organism and that, in most people, Hp would not cause more serious sequelae. This would suggest that there may be host-protective/inhibiting factors that would prevent the progression of Hp-induced active gastritis to cancer [23]. This theory is nevertheless challenged by other authors such as Agha and Graham through a multicentre study [24].
The retrospective nature of our study could underestimate the prevalence of Hp through selection bias. It is not known whether the patients were on antibiotic therapy and or under a proton pump inhibitor when the gastric biopsy was performed. Despite this limitation, our study gives interesting results.
5. Conclusion
The prevalence of Helicobacter pylori is high in Bouaké, like are other cities in developing countries. This study confirmed the involvement of Hp in chronic and active gastritis. Performing gastric biopsies in search of Hp during upper digestive endoscopies should be systematic. It would also be interesting to carry out a prospective multicentre study to clarify the links between Hp and precancerous and cancerous gastric lesions.
Acknowledgements
Our thanks to Prof. N’dah Kouamé Justin and Dr. Aman N’guiessan Alphonse from the Pathological Anatomy Department of Bouaké’s Teaching Hospital.