Oral form of auto-brewery syndrome.

Although previous cases of ethyl alcohol production by microorganisms present in the intestines, referred to as auto-brewery syndrome (ABS), have been reported, a recent case in our practice was characterized by the production of alcohol in the oral cavity. Our research indicates that legally significant levels of ethyl alcohol can be detected in exhaled air in cases where there has been no alcohol consumption but where the subject has oral candidiasis. In such cases, following the consumption of foods containing carbohydrates, a fermentation process occurs in the mouth, the first stage of which is glycolysis, proceeding according to the Embden-Meyerhof-Parnas pathway, which is typical in eukaryotes. The main organic substrate in this case is glucose, which is formed in the oral cavity from disaccharides (maltose, sucrose) by the activity of α-amylase. Some mutated fungal strains of the genus Candida acquire the ability to break down sucrose and produce glucoamylase. Glucose is converted into glyceraldehyde 3-phosphate and then into pyruvate. The next stage of fermentation is the decarboxylation of pyruvate into acetaldehyde, a reaction catalyzed by pyruvate decarboxylase. The final stage is the reduction of acetaldehyde to ethanol by alcohol dehydrogenase. Such endogenous production of alcohol can be confused with its consumption, which can cause not only legal, but also social and medical problems.