Oral and oropharyngeal colonization by Enterobacteriaceae: A narrative review on its epidemiology and clinical impact.

The family encompasses a large group of Gram-negative bacteria of the order Enterobacterales, which are habitual residents of the intestinal and urinary tracts, behaving only as allochthons in the oral cavity. There is no consensus regarding the prevalence, determinants and consequences of high aero-digestive colonization by this family of bacteria. In light of this, a narrative review was conducted on the epidemiology and clinical impact of oral and oropharyngeal colonization by , differentiating by age groups. A bibliographic search was conducted in four digital databases: PubMed/MEDLINE, Scielo, Google Scholar and Cochrane library of clinical and preclinical studies published in the last twenty years (2003 to 2023), on asymptomatic colonization of in the upper aero-digestive tract, its determinants and clinical impact. Oral and oropharyngeal colonization by was 38.24 and 39% on average, respectively. The genera spp. (68.75%), spp. (68.75%), spp. (43.75%), spp. (25%), and spp. (25%) were the most prevalent taxonomic groups in the oral cavity, especially in children and adolescents, while spp. (22.5%), spp. (15.5%) and spp. (8%) were the most prevalent in the oropharyngeal area of senile subjects. This colonization is shown to be associated with an increased risk of infectious and inflammatory episodes such as pneumonia, inflammatory bowel disease, periodontal disease, and progression of renal failure; with determinants that differ depending on age, with periodontal disease being a shared risk factor for senile and non-senile groups. The presence of enterobacteria in the upper aerodigestive tract is significant, predominating in children and adolescents, promoted by various factors that differ according to age and with systemic consequences of an infectious or inflammatory nature in certain types of hosts. Its role in the pathogenesis of oral diseases such as periodontitis is still not possible to specify.