Dentists Are at a Higher Risk for Oral Helicobacter pylori Infection

Frequency and risk factors of H. pylori infection among dental students: an observational cross-sectional study

Despite Helicobacter pylori infection remains asymptomatic in most people, it is associated with an increased risk of gastric cancer. Considering Egypt had the highest prevalence of H. pylori in healthy asymptomatic population in adults and pediatric age in past studies and currently salivary ELISA could be used for diagnosis of Oral H. pylori infection. Moreover, some researchers speculated that dentists and dental students might be at a higher risk for oral H. pylori infection because they are the most frequently exposed ones to saliva and dental plaque. This study aimed to determine risk factors associated with frequency of H. pylori among a sample of dental students for better management of the disease. 83 participants, with age (21-25 years), attending Faculty of Dentistry, Fayoum University were recruited. A structured questionnaire was used to collect information on sociodemographic parameters and risk factors for H. pylori. Direct inquiry about dyspeptic symptoms were done. Saliva samples were collected and tested for H. pylori antibodies. Overall seroprevalence was 22.9%. Participants in internship were more prone to be positive (p = 0.005). 32.6% of urban residents versus 10.8% of rural were H. pylori positive (p = 0.019). 75.0% of previous history of H. pylori infection versus 14.1% of those with no history were H. pylori positive p < 0.001. 70% of positive H. pylori participants reported positive clinical symptoms that were statistically significant. This study suggests that middle income, previous history of H. pylori and clinical symptoms of dyspepsia are risk factors of oral H. pylori with a decline in its prevalence in Egypt.

Human microbiomes in cancer development and therapy

Colonies formed by bacteria, archaea, fungi, and viral groups and their genomes, metabolites, and expressed proteins constitute complex human microbiomes. An increasing evidences showed that carcinogenesis and disease progression were link to microbiomes. Different organ sources, their microbial species, and their metabolites are different; the mechanisms of carcinogenic or procancerous are also different. Here, we summarize how microbiomes contribute to carcinogenesis and disease progression in cancers of the skin, mouth, esophagus, lung, gastrointestinal, genital, blood, and lymph malignancy. We also insight into the molecular mechanisms of triggering, promoting, or inhibiting carcinogenesis and disease progress induced by microbiomes or/and their secretions of bioactive metabolites. And then, the strategies of application of microorganisms in cancer treatment were discussed in detail. However, the mechanisms by which human microbiomes function are still poorly understood. The bidirectional interactions between microbiotas and endocrine systems need to be clarified. Probiotics and prebiotics are believed to benefit human health via a variety of mechanisms, in particular, in tumor inhibition. It is largely unknown how microbial agents cause cancer or how cancer progresses. We expect this review may open new perspectives on possible therapeutic approaches of patients with cancer.

Colonization by Various Morphological Forms of Helicobacter pylori in the Gingival Sulcus and Antrum of the Stomach

BACKGROUND

Helicobacter pylori eradication therapy can be considered effective if the result of its implementation is removed including all roots and rootlets from which surviving H. pylori can repopulate in the gastric mucosa. One of the reasons for the ineffectiveness of eradication therapy can be the continuous presence of viable coccoid forms of H. pylori in the oral cavity. Therefore, anti-Helicobacter eradication therapy should be supplemented by the sanitation of the oral cavity.

OBJECTIVES

The objective of this study is to determine the frequency of occurrence of H. pylori in the gastric mucosa and in the oral cavity in patients with chronic periodontitis or with chronic gastritis using immunocytochemical method and to evaluate the pathophysiological relationship between periodontitis and HP-associated acid-dependent stomach diseases mediated by H. pylori.

METHODS

A group of patients with chronic gastritis (70 participants, 46 women, 24 men, age: 24 - 55 years) and another group with chronic periodontitis before the start of surgical treatment (61 participants, 30 women, 31 men, age: 20 - 60 years) were examined for НР bacterial cells using immunocytochemical methods of staining gastric biopsy and exfoliate samples from the gingival sulcus surface. The participants did not take any antimicrobial medication before and during the examination. Routine staining was also performed to view microbiota in smears for both groups. The participants signed a voluntary consent agreement to undergo routine medical examinations and join the study at the Nikiforov Russian Centre of Emergency and Radiation Medicine, EMERCOM of Russia, where the ethical committee was made.

RESULTS

Immunocytochemical method could identify all stages of bacillary-coccoid transformation of H. pylori which accounted for 63.4-67.5% of cases. HP-antigenpositive bacteria were found in the oral cavity in both groups of examined patients. It was apparent that spiral forms of H. pylori were dominant over coccoid forms in the gastric mucosa in the antrum of the stomach, whereas coccoid forms of H. pylori were frequently found more in the oral cavity. Helicobacteriosis in the oral cavity was identified in chronic periodontitis.

CONCLUSION

We found certain pathogenetic connections between inflammatory lesions of the oral cavity and diseases of the internal organs of the gastrointestinal tract. Accordingly, we suggest the necessity to use proper medication for oral cavity sanitation along with anti-Helicobacter eradication therapy to influence the HP reservoir in the oral cavity and gingival sulcus. Additionally, bacterial cells of HP reside in the oral cavity in coccoid forms; therefore, the coccoid form of HP should become the second principal target in treating HP.