Auto-Brewery Syndrome - Causes, Symptoms, and Management

Introduction:

Auto-brewery syndrome (ABS) is considered a rare condition in which there is a production of alcohol in the gut. ABS is also known as gut fermentation syndrome. Ethanol production occurs through endogenous fermentation in the gastrointestinal system. This condition was first described in 1952 in Japan.

What is Auto-Brewery Syndrome?

Auto-brewery syndrome (ABS) is a condition in which ethanol is produced in the gut through fermentation by fungi or bacteria in the gastrointestinal system, oral cavity, and urinary system. This occurs due to alcohol intoxication when alcohol has not been consumed. This condition is reported because of a high sugar and carbohydrate intake.

Though this condition was described long ago, its name was coined in 1990. This condition was used many years ago to protect drivers from DUI cases. It is considered that a very long duration is required for high blood intoxication with ethanol to occur.

The production of ethanol inside the gut occurs very slowly as a part of normal digestion. When the fungi or bacteria become pathogenic, there may be an increase in the level of blood alcohol.

This condition is more commonly seen among those affected by diabetes, obesity, and Crohn's disease. It may also occur in healthy individuals.

Many strains of yeast and rare bacteria have been identified as pathogens. This condition is considered to be underdiagnosed. It is a rare condition even rarer that occurs in the oral cavity and urinary bladder. The ABS may be observed in children as well as among adults.

What Are the Causes of Auto-Brewery Syndrome?

Many yeasts and bacterial strains are thought to cause ABS. These include,

• Many fermenting yeasts, like Saccharomyces cerevisiae and S. boulardii, and many strains of Candida, like C. glabrata, C. albicans, C. kefyr, and C. parapsilosis, are thought to cause this condition.

• Many bacteria, like Klebsiella pneumonia, Enterococcus faecium, E. faecalis, and Citrobacter freundii, are thought to cause ABS.

• Common yeasts like Candida albicans, Candida tropicalis, Saccharomyces cerevisiae, and Torulopsis glabrata are thought to cause ABS.

• A genetic polymorphism that reduces the activity of the aldehyde dehydrogenase enzyme that is responsible for the hepatic metabolism of ethanol may be the reason for the increase in the levels of alcohol in the blood.

Few reports about demographics, diet, health history, or lifestyle factors are available. Though Saccharomyces cerevisiae is present in the body, it is thought to be a pathogen leading to ABS. This pathogen is a type of yeast that is harmless to the body, but it is overgrown in certain situations and causes problems.

When an individual with an overgrown pathogen in the gut takes a carbohydrate-rich diet and drinks, these foods start fermenting into alcohol. This reaction leads to a rise in blood alcohol concentration (BAC) levels.

Antibiotic use may also lead to this by causing a change in the gut environment.

Other underlying conditions like diabetes, liver cirrhosis, short bowel syndrome, chronic intestinal pseudoobstruction, and Crohn’s disease may also lead to ABS.

Among those already registered for increased endogenous ethanol levels, stress or skipping meals may increase the alcohol concentration in the blood.

What Are the Symptoms of Auto-Brewery Syndrome?

The symptoms of ABS are similar to those seen in the case of drunkenness. These include,

• Presence of altered mood.

• Anxiety.

• Dysphoria may be seen.

• Depression.

• Change in mental status.

• Presence of drowsiness.

• Brain fog.

• Seizures and ataxia can be observed.

• The affected person may experience the smell of alcohol in their breath.

• Fatty liver, cirrhosis of the liver, and pancreatitis may be observed.

Other symptoms include,

• Presence of headache.

• Nausea and vomiting may be seen.

• Belching may be observed.

• A loss of coordination is observed.

• Memory problems may be seen.

• They find it difficult to concentrate.

Symptoms of ABS may overlap with other conditions, such as chronic fatigue syndrome, depression, and alcoholism.

How to Diagnose Auto-Brewery Syndrome?

ABS is rare, and its symptoms overlap with those of other conditions. Hence, it needs a detailed diagnosis.

• A detailed medical history that includes dietary habits, consumption of alcohol, and symptoms related to the gastrointestinal system is required. Along with this, a comprehensive physical examination is to be done to determine unexplained alcohol intoxication.

• Basic laboratory tests, like complete blood count, are to be done.

• A comprehensive metabolic panel is to be done.

• A stool examination is to be done.

• These tests help in ruling out the other underlying conditions.

• The individuals are asked to use a breathalyzer to check their breath alcohol content (BAC). This measure should be confirmed with the concomitant blood alcohol level.

After these tests, the upper and lower endoscopies are done to learn about gastric, upper small bowel, terminal ileal, and colon secretions. These samples are further tested for pH, gram strain, culture, and antibiotic and antifungal sensitivity. Further antifungal sensitivity tests are performed when the specific fungal species is identified. This helps design further therapy.

After the endoscopy, the confirmatory test called the carbohydrate challenge test was done. This test should be performed only when breath and blood alcohol levels are zero. If the levels of alcohol are elevated, then the individual should wait until the level of alcohol becomes zero.

The individual should be under strict observation so that they do not consume alcohol and have zero alcohol in their blood and breath before performing a carbohydrate challenge test.

This test involves administering 200 g of glucose orally in an isolated setting. The testing of breath and blood alcohol levels is done at baseline zero, 0.5, 1, 2, 4, and 8 hours after glucose administration. Individuals under the test can eat any meal after administering 200 g of oral glucose. If the alcohol levels get elevated during this testing period, then the test may be halted, and the test is considered positive.

If individuals under the test are not found to be positive even after 8 hours, they can be returned and get the sample after 16 and 24 hours. This must be done, as some fungi may take more than 8 or 24 hours to ferment the carbohydrates.

Testing for stool samples is considered in the upper gastrointestinal tract as the presence of fungi is considered pathological and not the same in the lower gastrointestinal tract.

What Is the Treatment for Auto-Brewery Syndrome?

The treatment for ABS includes,

• Administration of intravenous fluids for hydration.

• The airway has to be maintained.

• Nutritional deficiencies and calorie correction are to be addressed.

• If alcohol withdrawal stabilizes, they should be treated with benzodiazepines.

Once the individual stabilizes, the targeted treatment can be initiated. The treatment should involve an interdisciplinary approach. This approach includes a gastroenterologist, a psychiatrist, and a nutritionist.

Dietary Changes: Avoiding carbohydrates and processed foods helps relieve the symptoms of ABS. Those who restrict carbohydrates should be given proteins to help them feel fuller for long periods of time.

A healthcare professional advises avoiding carbohydrates until the symptoms are resolved. Then, slowly, the introduction of carbohydrates can be done. Dietary changes must be discussed with the concerned doctor.

Medications: A healthcare professional may prescribe antifungals and antibiotics. Antifungals help reduce the fungi in the gut. These help reduce symptoms related to the gut that are caused by fungi.

Antifungals used in the treatment of ABS include,

• Fluconazole.

• Itraconazole.

• Nystatin.

• Echinocandins.

Individuals who do not respond to these may require stronger medications.

Probiotics: Probiotic supplements can be given to improve the gut microbiota. This helps in balancing the microbiome in the gut and inhibiting fungal growth.

Conclusion:

Auto-brewery syndrome is a rare condition in which ethanol is produced in the body due to overgrowth of the fungi in the gut. These individuals exhibit elevated blood alcohol, though they have not consumed it. Carbohydrates and processed foods are responsible for the elevation of blood alcohol. Hence, knowing about the ABS, its causes, symptoms, and management becomes important.