Megaesophagus microbiota and carcinogenesis

Abstract

Background - The risk of development of spin cell carcinoma of the esophagus is 33 times higher in patients with chagasic achalasia. It is possible that the production of N-nitroso compounds in the esophageal lumen by of bacterial action in the stasis liquid that reduce nitrates from diet into nitrites may play a role in this process. Aim - To analyze qualitatively and quantitatively the microbiota in chagasic megaesophagus with special attention to bacteria capable of transforming nitto reduction. Patients - Fifteen patients (six men and nine women) were prospectively studied, with ages varying from 28 to 73 years. Patients were divided into three sub-groups according to Rezende et al. classification of esophageal dilation (grade I, grade II and grade III). Method - The sample collection was performed using a method specially developed to avoid contamination with microorganisms of the oral cavity and oropharynx, using a Levine catheter n° 14 and a 7,5 oro-traqueal tube. Results - Ninety three point three percent of the cultures were positive, with great bacterial variability and predominance of a variety of aerobic Gram-positive and anaerobic bacteria. The bacterial concentrations were generally more elevated in grade III in comparison to grade I and grade II. Among the microorganisms found, Staphylococcus sp, Corynebacterium sp, Peptostreptococcus sp e a Veillonella sp were those with the capability of nitrate reduction. Conclusion - It was concluded that patients with megaesophagus present some bacteria in the esophageal lumen that are able to reduce nitrates intro nitrites, an important step in the formation of N-nitroso compounds.