Feasibility of investigating the association between bacterial pathogens and oral leukoplakia in low and middle income countries: A population-based pilot study in India

Abstract

Background Certain oral bacterial pathogens may play a role in oral carcinogenesis. We assessed the feasibility of conducting a population-based study in India to examine the distributions and levels of Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia in relation to oral leukoplakia (a potentially malignant disorder) and other participant characteristics. Methods This exploratory case-control study was nested within a large urban Indian cohort and the data included 22 men and women with oral leukoplakia (cases) and 69 leukoplakia-free controls. Each participant provided a salivary rinse sample, and a subset of 34 participants (9 cases; 25 controls) also provided a gingival swab sample from keratinized gingival surface for quantitative polymerase chain reaction (qPCR). Results Neither the distribution nor the levels of pathogens were associated with oral leukoplakia; however, individual pathogen levels were more strongly correlated with each other in cases compared to controls. Among controls, the median level of total pathogens was the highest (7.55×104 copies/ng DNA) among persons of low socioeconomic status. Salivary rinse provided better DNA concentration than gingival swab for qPCR analysis (mean concentration: 1.8 ng/μl vs. 0.2 ng/μl). Conclusions This study confirms the feasibility of population studies evaluating oral microbiome in low-resource settings and identifies promising leads for future research.

Association Between Oral Microbiota and Oral Leukoplakia: A Systematic Review

“…The selection of studies included is presented in Figure 1. Table 2 presents key information on seven studies [13][14][15][16][17][18][19] on the association between oral microbiota and oral leukoplakia included in the systematic review.…”

“…Each study is identified by a study ID, along with details such as the year of publication, country where the study was conducted, sample size (n), gender ratio, and mean age in years. [18], and Shridhar et al [19] examined the relationship between oral microbiota and leukoplakia using different methodologies and assessments. The studies varied in terms of the specific microbial species or taxa assessed within the leukoplakia patient population.…”

Leukoplakia in the Oral Cavity and Oral Microbiota: A Comprehensive Review

“…Nonetheless, other saliva-based studies were able to identify significant differences in the microbiome composition between OLK and healthy controls [12,[15][16][17][18]. Moreover, although through a highly biased study (i.e., time lag between OLK and sampling; lack of histologic assessment of OLK), Shridhar et al showed a better proportion of quantifiable pathogens from salivary rinse rather than gingival swabs for three selected species [18].…”

“…Based on previous reports, Shridhar et al did not investigate the whole microbiome in their population-based study. Instead, they focused on three renowned bacterial pathogens: Porphyromonas gingivalis, Fusobacterium nucleatum and Prevotella intermedia [18].…”