Hi Re-do,
I'm not sure if you have read all the stuff on d-lactic acid producing bacteria, so I have put together a few links below, which you might find of interest.
firstly, I just wanted to tell you about a study taking place in Australia regarding d-lactic acid in CFS,. This study is furthering research done by a team that found d-lactic acid producing bacteria in higher amounts in the stools of CFS patients, than in healthy controls. Here is a link to the original study.
http://www.cfids-cab.org/rc/Sheedy.pdf
The new study will measure d-lactate in stool, urine and blood samples of CFS patients, and compared to samples of healthy controls, to see whether CFS patients have a higher level of d-lactic acid. Here is their application, together with brief discussion.
http://sacfs.asn.au/download/Lactic%...pplication.pdf
As part of this study a questionnaire was given to the CFS patients, regarding lactic acid symptoms, you can find this here:
http://www.sacfs.asn.au/download/Lac...stionnaire.pdf
I wanted to also point out that research has also been carried out into lactate levels in the brain fluid of CFS patients, and was found to be higher. D-lactic acid crosses the bbb, and causes neurological changes that are said to be strikingly similar to CFS symptoms. Here is an abstract of a recent study.
Increased ventricular lactate in chronic fatigue syndrome measured by 1H MRS imaging at 3.0 T. II: comparison with major depressive disorder.
Murrough JW, Mao X, Collins KA, Kelly C, Andrade G, Nestadt P, Levine SM, Mathew SJ, Shungu DC.
Department of Psychiatry, Mount Sinai School of Medicine, New York, NY, USA.
Abstract
Chronic fatigue syndrome (CFS), a complex illness characterized by fatigue, impaired concentration, and musculoskeletal pain, is often misdiagnosed as a psychiatric illness due to the overlap of its symptoms with mood and anxiety disorders. Using proton magnetic resonance spectroscopic imaging ((1)H MRSI), we previously measured levels of the major brain metabolites in CFS, in generalized anxiety disorder (GAD), and in healthy control subjects, and found significantly higher levels of ventricular cerebrospinal fluid (CSF) lactate in CFS compared to the other two groups. In the present study, we sought to assess the specificity of this observation for CFS by comparing ventricular lactate levels in a new cohort of 17 CFS subjects with those in 19 healthy volunteers and in 21 subjects with major depressive disorder (MDD), which, like GAD, is a neuropsychiatric disorder that has significant symptom overlap with CFS. Ventricular CSF lactate was significantly elevated in CFS compared to healthy volunteers, replicating the major result of our previous study. Ventricular lactate measures in MDD did not differ from those in either CFS or healthy volunteers. We found a significant correlation between ventricular CSF lactate and severity of mental fatigue that was specific to the CFS group. In an exploratory analysis, we did not find evidence for altered levels of the amino acid neurotransmitters, gamma-aminobutyric acid (GABA) and glutamate + glutamine ('Glx'), in CFS compared to MDD or healthy controls. Future (1)H MRS studies with larger sample sizes and well-characterized populations will be necessary to further clarify the sensitivity and specificity of neurometabolic abnormalities in CFS and MDD.
Dr. Dikoma Shungu "will build on a preliminary study showing that brain fluid of CFS patients contains significantly elevated levels of lactic acid, or lactate, a substance important in metabolism." "If this study is successful, brain lactate levels could provide an objective diagnostic biomarker for CFS and evidence of a metabolic problem in these patients."
D-lactic acidosis is a condition that is almost exclusively taught to gastroenterologist's, however they only see it in patients with a shortened bowel, as these patients cannot fully digest carbohydrates due to surgery or disease of the small intestine. It is caused by d-lactic acid producing bacteria fermenting carbohydrates, which changes the pH of the bowel, favouring acid loving bacteria at the expense of other gut bacteria. D-lactic acidosis can present without a change in the anion gap, making it invisible in blood tests, unless specifically testing for. See below:
"There are two major ways acidosis is defined from routine laboratory data. First, organic acids may be added to the body so quickly that both the H and the anion are retained; this results in metabolic acidosis and an elevated value for the plasma anion gap.
Second, metabolic acidosis may be present without a rise in the plasma anion gap. In this latter setting, either the D-lactate anion was retained in the lumen of the GI tract (with the H being absorbed or titrated by bicarbonate in the lumen of the GI tract), or it was excreted in the urine, but in either case, the cation lost with it was Na and/or K ion (not a H or NH4 ion). This latter type of metabolic acidosis is akin to the over-production of hippuric acid in glue sniffers. Since D-lactate anions are reabsorbed by the kidney much less readily than is L-lactate, as time progresses, the anion gap may decline without resulting in a rise in the plasma bicarbonate concentration-that is, D-Iactate is excreted as its Na or K salt (Fig. 6). Hence there are a number of mechanisms that may contribute to the presentation whereby the rise in the plasma anion gap might not match the fall in the plasma bicarbonate concentration. Not only might this lead to a diagnostic problem, it has implications for therapy because, once the organic anions are excreted as their Na or salts, these anions are no longer available for metabolism to regenerate bicarbonate, and the patient might have developed a deficit of Na and/or K4."
Path labs are not able to test for d-lactic acid, as they do not have the d-lactate assy kit required and would have to ship a test in, however I believe d-lactic acid can also be screened for in urine tests.
On a CFS discussion group I found the post below, from a lady saying she had tested for high levels of d-lactate, but this testing was not done through a GI, and I am presuming that the significance was lost on their doctors. Normal levels of d-lactate are between 0.0-0.25 in healthy individuals, and her levels were around 2.4mmol/L, which is the level that neurological changes occur in short bowel patients suffering from dla. They should have been urgently referred to a GI, for formal testing, treatment and monitoring of their d-lactic levels, until the levels returned to normal. It is seen as a serious condition. Treatment is antibiotics, sodium bicarbonate, either orally or IV and a low carb diet, in cases where there is a recurrence of d-lactic. It can be a case of trial and error, before the correct antibiotics are found, depending on the resistance of the bacterial overgrowth.
http://www.endfatigue.com/forums/viewtopic.php?f=17&t=1271
Here are some papers regarding d-lactic acidosis, however they are all in patients with a shortened bowel. The first one has a good graph of symptoms, which are very similar to some CFS symptoms. I would imagine that in a short bowel patient, their symptoms would be very severe, more so than in CFS.
http://hkjpaed.org/details.asp?id=577&show=1234
This paper talks of the possibility that d-lactic acidosis may occur in a human with a complete bowel, when they were investigating d-lactic acidosis in a calf model. "The mechanism is likely similar to that documented for D-lactic acidosis in SBS in humans except the etiology of the malabsorption is viral infection induced villous atrophy rather than surgical removal of the small intestine."
It goes on to say
"There is a possibility, although it has not been described, that a similar scenario could occur in diarrheic monogastrics, including humans"
http://jn.nutrition.org/content/135/7/1619.full
This one talks about d-lactate having a circadian rythm, so afternoon testing might show it up. Typically, patients would have normal serum lactate, but high urinary lactate, in an afternoon test, the high urine test would suggest d-lactate.
http://www.clinchem.org/cgi/reprint/41/1/107.pdf
The main symptoms of d-lactic acidosis are severe lethargy, changes in gait and co-ordination, slurred speech, or difficulty in speaking, blurred vision, headaches, blunted judgement, abusive or aggressive behaviour, irritability, inability to concentrate, the feeling of being drunk in the absence of alcohol, hyperventilation, craving carbohydrates, nausea and nystagmus.
Sorry about the long post, hope it does not tire you out too much
Glynis x