Dear Glynis,
I forgot, there are many causes of Bacterial Overgrowth, as I had stated earlier D-Lactic acidosis is just one form of Bacterial Overgrowth. There may be a number of different and combined forms Bacterial Overgrowth that give rise to multiple metabolites which are toxic, depending on type and quantity in the Small Intestine. I believe that it may be D-Lactic or similar Bacterial Overgrowth in those suffering ME, because D-Lactic Bacteria produce the Neurotoxin D-Lactic acid. Sheedy et al (Increased D-Lactic acid Bacteria in CFS) later concluded in their 2017 Report that there may be a number of other metabolites involved including D-Lactic acid.
Small intestinal bacterial overgrowth syndrome
Jan Bures,
Jiri Cyrany,
Darina Kohoutova,
Miroslav Förstl,
Stanislav Rejchrt,
Jaroslav Kvetina,
Viktor Vorisek, and
Marcela Kopacova
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Abstract
Human intestinal microbiota create a complex polymicrobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO). SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacteriostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insufficiency, immunodeficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, fistulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Non-invasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be complex, addressing all causes, symptoms and complications, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO.
Keywords: Bacterial overgrowth, Breath test, Hydrogen, Methane, Small intestine
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INTRODUCTION
Human intestinal microbiota create a complex polymicrobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. The duodenum and proximal jejunum normally contain small numbers of bacteria, usually lactobacilli and enterococci, gram-positive aerobes or facultative anaerobes (< 104 organisms per mL). Coliforms may be transiently present (< 103 bacteria per mL) and anaerobic
Bacteroides are not found in the jejunum in healthy people. Up to one third of jejunal aspirates might be sterile in healthy volunteers. The distal ileum is a transition zone between sparse populations of aerobic bacteria of the proximal small intestine and very dense populations of anaerobic micro-organisms in the large bowel[
1-
3]. The epithelial surface of the small intestine in a healthy human is not colonised. Occasional groups of bacteria can be found in low concentrations within the lumen. Bacteria do not form clusters and spatial structures, and the luminal contents are separated from the mucosa by a mucus layer[
4].
Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequences for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO).
Increased d-lactic Acid intestinal bacteria in patients with chronic fatigue syndrome.
Sheedy JR1,
Wettenhall RE,
Scanlon D,
Gooley PR,
Lewis DP,
McGregor N,
Stapleton DI,
Butt HL,
DE Meirleir KL.
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Abstract
Patients with chronic fatigue syndrome (CFS) are affected by symptoms of cognitive dysfunction and neurological impairment, the cause of which has yet to be elucidated. However, these symptoms are strikingly similar to those of patients presented with D-lactic acidosis. A significant increase of Gram positive facultative anaerobic faecal microorganisms in 108 CFS patients as compared to 177 control subjects (p<0.01) is presented in this report. The viable count of D-lactic acid producing Enterococcus and Streptococcus spp. in the faecal samples from the CFS group (3.5 x 10(7) cfu/L and 9.8 x 10(7) cfu/L respectively) were significantly higher than those for the control group (5.0 x 10(6) cfu/L and 8.9 x 10(4) cfu/L respectively). Analysis of exometabolic profiles of Enterococcus faecalis and Streptococcus sanguinis, representatives of Enterococcus and Streptococcus spp. respectively, by NMR and HPLC showed that these organisms produced significantly more lactic acid (p<0.01) from (13)C-labeled glucose, than the Gram negative Escherichia coli. Further, both E. faecalis and S. sanguinis secrete more D-lactic acid than E. coli. This study suggests a probable link between intestinal colonization of Gram positive facultative anaerobic D-lactic acid bacteria and symptom expressions in a subgroup of patients with CFS. Given the fact that this might explain not only neurocognitive dysfunction in CFS patients but also mitochondrial dysfunction, these findings may have important clinical implications.
PMID:
19567398
[Indexed for MEDLINE]
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Another Abstract:
Ovid MEDLINE and PubMed databases were used to search the published literature. For Ovid MEDLINE (1966 to December 2006, English language only) three primary search terms (bacterial overgrowth, small intestine overgrowth, and small intestine bacterial overgrowth) were individually coupled with a larger number of secondary search terms (epidemiology, incidence, prevalence, populations at risk, symptoms, pathogenesis, pathophysiology, inflammation, malabsorption, complications, vitamin deficiency, motility disorders, scleroderma, gastroparesis, chronic intestinal pseudo-obstruction, celiac disease, irritable bowel syndrome, renal failure, cirrhosis, alcohol abuse, elderly, aging, diabetes, hypochlorhydria, surgery, malnutrition, diarrhea, evaluation, diagnosis, breath testing, duodenum, jejunum, aspirates, breath tests, lactulose, treatment, antibiotics, rifaximin, tetracycline, metronidazole, ciprofloxacin, amoxicillin/clavulanate, probiotics, duration, resistance). For PubMed (no time limit), a similar search process was followed. All identified articles were then manually searched for other relevant studies. Only published manuscripts are included in this review; abstracts are not included.