Bacterial Dysbiosis

Intestinal overgrowth of an organism called Klebsiella plays a role in determining who is affected by ankylosing spondylitis and how severely.  Research by doctors at King's College has uncovered a tissue similarity between this organism and the spine.  In an autoimmune reaction to excessive amounts of Klebsiella, the immune system attacks the spine.  Controlling this dysbiosis by diet reduces symptoms of the disease.

Abnormal bacterial populations may consume cobalamin, contributing to B12 deficiency states and resulting in megaloblastic anemia.

Some bacterial infections of the small bowel increase passive intestinal permeability.  IBS has been studied in patients with diarrhea, cramps and specific food intolerances.  Abnormal fecal flora has been a consistent finding, with a decrease in the ratio of anaerobes to aerobes, apparently due to a deficiency of anaerobic flora.  Previous exposure to antibiotics – metronidazole in particular – was associated with the development of this disorder.

During the early 1980s, exaggerated immunologic responses to components of the normal fecal flora were proposed as possible mechanisms behind inflammatory bowel disease.  Little progress has been made in confirming or disproving this theory, although bacterial overgrowth of the jejunum has been found in 30% of patients hospitalized for Crohn's disease, in which it contributes to diarrhea and malabsorption.  The demonstration of increased intestinal permeability in patients with active Crohn's disease and in healthy first degree relatives suggests the existence of a preexisting abnormality, such as dysbiosis, that allows an exaggerated immune response to normal gut contents to occur.

Elimination diets can induce remission in Crohn's disease as effectively as prednisone.  The primary bacteriologic effect of elemental diets is to lower the concentration of Lactobacilli in the stool drastically without altering levels of other bacteria.

Immunologic responses to gut flora have been advanced by several authors as being important causative factors of inflammatory joint diseases.  It is well-known that reactive arthritis can be activated by intestinal infections with Yersinia, Salmonella and other enterobacteria.  In some cases bacterial antigens have been found in synovial cells and may enter the circulation because of the increased intestinal permeability associated with the intestinal infection.  Increased intestinal permeability and immune responses to bacterial debris may cause other types of inflammatory joint disease as well.

Fecal and duodenal flora in patients with atopic eczema have been studied.  Evidence of small bowel dysbiosis and subtle malabsorption phenomena was found in the majority of cases.

Epidemiologic and experimental data implicate putrefactive dysbiosis in the development of colon cancer and breast cancer.  A putrefaction dysbiosis is accompanied by an increase in fecal concentrations of various bacterial enzymes which metabolize bile acids to tumor promoters and deconjugate excreted estrogens, raising the plasma estrogen level.

A putrefaction dysbiosis is accompanied by an increase in fecal concentrations of various bacterial enzymes which metabolize bile acids to tumor promoters.

Small bowel parasites may predispose a person to bacterial overgrowth in the small intestine.

Research suggests that gastritis and ulcers are triggered by bacterial overgrowth, rather than by stomach acidity.  Long-term treatment of patients with potent acid blockers (proton pump inhibitors) which produce a more alkaline environment that is unfriendly to acid-tolerant bacteria such as Helicobacter pylori, may actually allow the overgrowth of other types of bacteria in the stomach, including Lactobacillus, Enterobacter, Staphylococcus and Propionibacterium which can result in inflammation, gastritis and ulceration. [Gastroenterology, Jan 2002]

It is likely that both yeast and bacterial overgrowth commonly occur together; overgrowth of either can lead to Leaky Gut Syndrome.

A variety of bacterial pathogens can cause severe gastrointestinal symptoms such as bloody diarrhea, fever or abdominal pain.  In addition, many of these intestinal microbes can exacerbate or cause flare-ups of symptoms in patients who already have ulcerative colitis.

Citrus seed extract may be a desirable first line of treatment because of its broad spectrum of antibacterial, antifungal and antiprotozoan benefits.  The usual dose required is 600-1600mg per day.  Animal studies have shown no toxicity except for intestinal irritation producing diarrhea at very high doses.  The mechanism of action is not known; there is no evidence of systemic absorption.

Larch Arabinogalactan acts as a food supply for friendly bacteria.  The term used to describe this action is "prebiotic".  The most well known prebiotic substance is "fructooligosaccharides" or "FOS".  Larch Arabinogalactan acts in the same manner as FOS in humans.  The effect is to increase good bacteria such as bifidobacteria and lactobacillus, while decreasing bad bacteria.

If inflammation is present from this over-population of harmful bacteria, the regular use of Robert's Formula may help soothe the intestinal lining and reduce pain.

Bayberry leaf (or other sources of the alkaloid berberine) appears to kill enterobacteria, yeasts and amoeba.  The control of dysbiotic symptoms usually requires several grams per day.

The claimed benefits of drinking Kombucha tea may be derived solely from its ability to help correct an intestinal flora imbalance.

How do the friendly bacteria keep the bad bacteria in check?  Think of a crowded theater.  You walk in, and there is no place to sit; all the seats are taken.  So you can't stay.  It is the same with bacteria.  There are only a certain number of "seats" in the colon.  If they're all taken by friendly bacteria, then there's no chance for the bad bacteria to set up shop and start to duplicate themselves.

According to most researchers, normal probiotics should be more numerous than the cells of the intestinal lining itself.  One of the ways to help reestablish a balanced bacterial population in the GI tract is the use of probiotic supplements.  There are many products on the market containing a variety of organisms and a general approach could be taken using a broad spectrum probiotic formula.  However, a better method is to discover the type of imbalance by testing and then supplementing those specific bacteria that are needed.  Bringing these normally-occurring bacteria into balance will help prevent the overgrowth of more pathogenic organisms.

Bifidobacteria are the predominant lactic acid bacteria of the colon with a concentration that is 1000 times higher than Lactobacilli.  Administration of Bifidobacterium breve to humans and animals reduces fecal concentrations of Clostridia and Enterobacter species, ammonia, and toxin-releasing bacterial enzymes including beta-glucuronidase and tryptophanase.  Bacillus laterosporus, a novel organism classified as non-pathogenic to humans, produces unique metabolites with antibiotic, antitumor and immune modulating activity.  This organism is available as a food supplement in the United States.  It has been found to be an effective adjunctive treatment for control of symptoms associated with small bowel dysbiosis in a number of patients.

Fructose-containing oligosaccharides (FOS), found in vegetables like onion and asparagus, have been developed as a food supplement for raising stool levels of Bifidobacteria and lowering stool pH.

Antibiotic drugs may either cause or help control dysbiosis, depending upon the drug and the nature of the disorder.  Where contamination of the small bowel by anaerobes is the problem, metronidazole or tetracyclines may be beneficial.  When enterobacterial overgrowth predominates, ciprofloxacin is usually the drug of choice because it tends to spare anaerobes.  Herbal antibiotics may be preferred because of their greater margin of safety and the need for prolonged antimicrobial therapy in bacterial overgrowth syndromes.

A microbiological assessment of bacterial populations in the GI tract is important for determining the nature of the imbalance when dysbiosis is suspected.  Repeat testing should occur after treatment to ensure that the imbalance has been corrected.

The most useful test for large intestine dysbiosis is a Comprehensive Digestive Stool Analysis (CDSA) which includes an evaluation of many different aspects of digestion as well as a report on bacterial growth.