Changes of Serum Electrolytes and Serum Vitamin C Levels in a Sample of Iraqi patients Infected with Helicobacter pylori ( H. pylori )

Helicobacter pylori ( H. pylori ) is widespread and involved in the pathogenesis of the majority of stomach and duodenal diseases. Reduced stomach acidity facilitates the initial infection. Electrolytes (sodium, potassium, and chloride) are essential for the production of stomach acid. This study aimed to observe any changes in the levels of serum electrolytes (Na, K, and Cl) and serum vitamin C levels in a sample of Iraqi patients infected with H. Pylori . We studied 30 infected patients with H. Pylori and 30 matched healthy controls. The results revealed that the serum sodium, potassium, and chloride levels were significantly decreased ( p = 0.002, 0.003 and 0.0001, respectively) in the patients infected with the H. Pylori group in comparison with those of the healthy controls. Also, vitamin C levels were significantly lower in patients infected with H. Pylori than in the control group ( p = 0.001). The present results suggest that these changes may be attributed to or contribute to the infection itself through changes in gastric acidity, and this needs further study.


Introduction
Helicobacter pylori (H. pylori) is a spiral-shaped gram-negative bacterium [1,2]. It is among the most common bacterial stomach infections [3], and it infects more than half of the global population, with an estimated 4.4 billion people worldwide affected [2,4]. H. pylori prevalence in developed countries is between 30 and 50%, while it ranges between 85 and 95% in developing countries [5]. In Baghdad/Iraq, the rate of infected populations with H. pylori infection is more than 58%, as was recorded in two studies [6,7]. Also, several studies in Iraq have shown a relationship between H. pylori infection and several pathological conditions, such as Hashimoto's thyroiditis [8], atrophic gastritis [9], gallbladder [10], dyspeptic [11], type 2 diabetes [12] obesity [13], male infertility [14], and skin disorders [15]. H. pylori colonization normally occurs in childhood, but symptoms usually do not appear until adulthood. It is unknown if childhood colonization produces symptoms or changes in gastric acidity [16]. H. pylori cannot survive in an overly acidic stomach, and to survive, it requires a pH close to neutral [17,18,19]. Therefore, the initial infection depends on temporal hypoacidity, where H. pylori attacks the lining that protects the stomach [20,21,22]. The present study aims to observe any changes in the levels of serum electrolytes (Na, K, and Cl) and serum vitamin C levels in a sample of Iraqi patients infected with H. Pylori.

Material and methods 2.1. Studied groups
A case-control study was performed on 30 patients who were attending the endoscopic unit at the Baghdad Medical City teaching hospital for gastroenterology and hepatology in Baghdad with clinical manifestations of gastritis, nausea, and bloating, and who were confirmed to be infected with H. pylori infection by diagnostic tests. From August to October 2021, the serum samples from these patients were collected. Patients who had non-steroidal anti-inflammatory medicines in addition to H. Pylori eradication therapy was excluded from the study. Patients with other comorbidities were also excluded from the study. The diagnosis was made under the supervision of the specialists. For comparison purposes, 30 healthy volunteers were used as a control. They had no previous history of any complaints of gastrointestinal tract disease and negative diagnostic tests. The study protocol conforms to the ethical guidelines, which have been endorsed by the College of Science, University of Baghdad Ethics Committee, and all participants provided written consent.

Diagnostic tests for H. pylori infection
Two kits were used to diagnose the presence of H. pylori infection. The first was the Heliforce breath test kit manufactured by Beijing Richen-Force Science and Technology Co. Ltd. The second was the OnSite H. pylori Ag Rapid Test (in the human feces), manufactured by CTK Biotech.

Blood sample collection
From each participant, five milliliters of venous blood samples were collected in serumseparating tubes (SST) at room temperature. Serum was obtained by centrifuging the clotted blood at 3000 rpm for ten minutes. The obtained clear serum was stored frozen at -20 •C until laboratory determination of the level of electrolytes and vitamin C.

Assay of electrolytes (Na + , K + and Cl -) Levels
Serum levels of electrolytes were determined via the colorimetric method using a commercial kit manufactured by Human Company in Germany.

Vitamin C (Ascorbic acid) level
The serum level of vitamin C was determined by the method of Nino and Shah [23] using a DTCS reagent [a mixture of 2,4-dinitrophenylhydrazine (2%) + thiourea (5%) + copper sulfate (0.6%)] at λ = 520 nm. Trichloroacetic acid (6%) (TCA) was used instead of metaphosphoric acid (6%) as a protein-precipitating agent. The concentrations of vitamin C in samples were obtained from the standard curve using ascorbic acid as a standard and expressed in g/L.

Statistical analysis
Data were statistically analyzed using the package IBM SPSS Statistics for Windows, version 22. Data normality was assessed using the Shapiro-Wilk normality test. The student ttest was used to test the differences between the studied groups, and the P-value was considered significant if it was < 0.05.

Baseline characteristics
The baseline characteristics of patients infected with H. Pylori and controls are illustrated in Table 1.

Electrolytes (Na + , K + and Cl -) and vitamin C levels
From the results presented in Table 2, the levels of serum sodium, potassium, and chloride were significantly decreased in the patients infected with H. Pylori compared to the control (p = 0.002, 0.003, and 0.0001, respectively). Also, levels of vitamin C were significantly decreased in patients infected with H. Pylori compared with the control group (p = 0.001).

Discussion
This study was conducted on Iraqi patients infected with H. pylori and during the study, it was noticed that most patients infected with H. pylori were males, which may give a clue that gender may play a role in H. pylori-related infection, and this observation agrees with many other studies [24,25,26] that confirmed the male predominance of H. pylori. The results showed that there were more electrolyte disturbances in patients infected with H. pylori in comparison with healthy controls. There was a decrease in the level of serum sodium and potassium, although they were within the lower limits of the normal range, and a decrease in the level of serum chloride, which was lower than the lower limit of the normal range. Our results are contradictory to the results of Eden et al. [27] and Aratani et al. [28], as they found a strong relationship between H. pylori infection and hypernatremia rather than low serum sodium. The most common electrolyte imbalance encountered in clinical practice is hyponatremia, and several medications are associated with it, such as proton pump inhibitors, which cause hyponatremia [28,29,30]. It is important to be aware of medication-induced hyponatremia, especially that caused by proton pump inhibitors. Thus, it is preferable not to administer any other drug from the same class when the syndrome of inappropriate antidiuretic hormone secretion caused by a proton pump inhibitor is detected [31]. Although the interactions between H. pylori and the stomach are quite complicated, low gastric acidity makes it easier for H. pylori to proliferate and infect the stomach [17]. Electrolytes (sodium, potassium, and chloride) are essential for the production of very extreme acid (HCl; pH is about 0.8) in the stomach. A hydrogen-potassium pump is the primary driving force for parietal cell hydrochloric acid secretion. Therefore, any inhibition of the pH proton pump by proton pump inhibitors will decrease the pH of the stomach and enhance the growth of H. pylori bacteria and then the invasion of the gastric mucosa [28,32]. Additionally, intragastric pH is the most important factor influencing the observed drop in the level of vitamin C in gastric juice when there is hypochlorhydria; pH rises intragastrically, which leads to vitamin C being converted into the less active form, resulting in irreversible inactivation of ingested vitamin C [33,34]. As shown in some studies, H. pylori infection reduced the level of vitamin C in gastric juice, such as in a study by Woodward, Pedoe, and McColl in the UK, which included randomly selected men and women aged 25 to 74 [33]. Also, in a study by Waring et al. suggested that the eradication of H. pylori may increase the level of vitamin C in gastric juice [35].

Conclusion
H. pylori is associated with many extragastric abnormalities. One of these is the change in the levels of serum electrolytes (Na, K, and Cl) and serum vitamin C levels in infected patients. These changes may be attributed to or contribute to the infection itself through changes in gastric acidity, and this needs further study.

Ethical Clearance
The Research Ethical Committee at scientific research by ethical approval of both environmental, health, higher education, and scientific research ministries in Iraq.

Conflict Of interest
The authors declare that they have no conflict of interest.