nemoci-sympt/GASTROENTEROLOGIE/sibo/priciny-rizikove-faktory-asociovane
Alkoholizmus
Celiakie
Divertikly
- Výdutě stěny střeva, v nichž se mohou bakterie zachytávat
Fibromyalgie
- Fibromyalgici mají střevní potíže - nadýmání, bolesti břicha, průjem, IBS - syndrom dráždivého střeva.
- 8 z 10 z nich má narušenou střevní pohyblivost [4]
Co je příčina a co následek ???
- Několik studií ukazuje, že jak fibromyalgie, tak IBS mají často abnormální laktulózové dechové testy (LBT) [4]
- Vyšší Hydrogen production on the breath test, koreloval se somatickými bolestmi !!!
- An abnormal lactulose breath test is more common in fibromyalgia than IBS.
- In contrast with IBS, the degree of abnormality on breath test is greater in subjects with fibromyalgia
- And correlates with somatic pain :[5]
- LBT test na SIBO je pozitivní u téměř všech pacientů s fibromyalgií.
- Endotoxiny jsou v.s. zodpovědné za hyperalgesii - zvyšují vnímání bolesti v těle :[5]
- Endotoxin (LPS nebo lipopolysacharid)
- Bakteriální translokace, která je v SIBO běžná
- Výsledkem je produkce endotoxinů a systémové účinky :[5]
- Aktivní či pasivní penetrace živých mikroorganismů a jejich toxických produktů přes epiteliální vrstvu sliznice do lamina propria mucosae
- Mikroorganismy odtud migrují do mezenteriálních lymfatických uzlin a/nebo do extraintestinálních lokalit
- Za normálních podmínek se jedná o malé množství baktérií, které jsou ničeny imunitním systémem v lamina propria.
- Translokace je možná teprve při jejich vysokém množství, v literatuře je uváděno až 108 baktérií v 1 gramu stolice. :[5]
Gastroparéza
- První vlna peristaltiky začíná v žaludku
- Pokud je toto narušeno, může to souviset se SIBO
Hypochlorhydrie
- Snížená tvorba žaludeční kyseliny
Neuropatie
Diabetická
- Poškozeny nervy ovlivňující pohyblivost střev
Při Parkinsonově nemoci
- Celkové snížení pohyblivosti
Parasympatolytika
Rozacea
Sklerodermie
Sympatomimetika
Adheze nitrobřišní po operacích
- Narušení peristaltické vlny / funkce ileocékální chlopně
Poruchy funkce hladké svaloviny tenkého střeva
Deficit draslíku - hypokalemie
Deficit vit. B1
Syndrom dráždivého tračníku - IBS - Iritable bowel syndrome
- Když nemohou najít celiakii, Crohnovu chorobu nebo jiné fyzické abnormality v trávicím traktu
- Neřekne nic jiného než to, co jste už dávno věděli: máte zažívací problémy neznámé příčiny.
- Začněte hledat příčinu Vašeho IBS:
- Infekce bakteriemi,
- Nesnášenlivost lepku,
- Nesnášenlivost mléka a mléčných výrobků
- Nesnášenlivost fruktózy nebo jiných potravin
- Nebo byste možná měli zvážit, zda nemáte SIBO
- Klasické příznaky:
- Bolesti břicha,
- Plynatost, nadýmání
- Průjem / zácpa
- Postihuje i tenké střevo a je poměrně běžný
- Až 84% lidí s IBS má ve skutečnosti SIBO [1]
- Také spojeno se všemi druhy systémových příznaků
- Vč. zvýšení střevní propustnosti
- Primárním onemocněním je SIBO a dráždivý tačník je až sekundární syndrom [4]
- Někteří pacienti mají IBS po infekční gastroenteritidě [4]
- IBS umožní vznik SIBO. [4]
- IBS a SIBO mají identické symptomy [4]
- U IBS však musí být vodíkový dechový test s laktulózou negativní [4]
- Pozitivní u SIBO = pak nejde o IBS, přestože jsou splněna diagnostická kritéria. [4]
- SIBO u IBS nehraje významnější etiopatologenetickou roli. [4]
SRB a methanogeny
- The domination of mixed fecal cultures by SRB
- Clearly demonstrated more than 30 years ago
- Significant methane production
- By fecal cultures sampled from individuals with a positive methane breath test
- When these cultures were mixed with non-methanogenic fecal cultures,
- Methane production was almost completely inhibited
- With high sulfide production recorded instead
- V.s. pH was lower in the earlier experimentation, which would have been more favorable to the SRB.
- Methane production was recoverable
- Only when sulfate reduction was chemically inhibited.
- Hydrogen is only essential to the methanogens
Acetate production
- Remained relatively consistent between cultures
- Reductive acetogenesis should not be favorable in competition with sulfate-reduction and methanogenesis
- Methanogenesis dominated cultures grown from a mixture of methanogenic and non-methanogenic fecal samples
- Thermodynamic advantages of SRB may not be correct for all species in the GIT
- Possibility that pH played a role
- Colonized mice with Bacteroides thetaiotaomicron combined with M. smithii
- Produced mainly
- Rapidly reached much higher intestinal population densities than the SRB combination
- Increasing host adiposity compared with both the SRB combination and mono-association with B. thetaiotaomicron
- Upregulation of the expression of genes involved in the production of the enzyme pyruvate-formate lyase
- Increased production of formate
- Can be utilized by M. smithii
- More acetate production in the methanogenic association, with reduced propionate and butyrate
- Reduction in the cecal NADH/NAD+ ratio
- Metabolism of M. smithii created a more favorable environment for the breakdown of sugars by B. thetaiotaomicron
- Colonized mice with Bacteroides thetaiotaomicron combined with SRB
- Only minimal gene expression changes were associated
- Acetogen cross-feeding in the mouse GIT
- Demonstrated between B. thetaiotaomicron and B. hydrogenotrophica
- Increased the efficiency of fermentation by B. thetaiotaomicron
- Acetogen reduced the NADH/NAD+ ratio in fecal samples
- Regeneration of NAD+ is facilitated by the reductive acetogenesis carried out by B. hydrogenotrophica
- SRB Desulfovibrio vulgaris and the methanogen Methanococcus maripaludis in vitro
- SRB is able to convert lactate to
- Acetate, CO2 and hydrogen
- Methanogen utilizes the released CO2 and hydrogen for methane production
- Cross-feeding reduces the partial pressure of hydrogen
- Creating a more favorable metabolic environment for the SRB
- D. vulgaris
- Acts as a net hydrogen producer
- Competition between the functional groups is environmentally dependent
- D. piger and the mucin degrader B. thetaiotaomicron
- With chondroitin sulfate, the SRB showed good growth, and high levels of hydrogen sulfide were produced
- Engineered B. thetaiotaomicron strain
- Unable to synthesize a certain sulfatase enzyme
- Reduced overall culture growth and sulfide production
- Hydrogen flux between members of the microbiota is extremely difficult.
- A number of such studies suggested that
- Methanogens and SRB were mutually exclusive, or nearly so
- Due to competition for hydrogen, the only mutual substrate of the two
- Rural South Africans
- Being predominantly methanogenic
- UK cohort
- Had higher levels of SRB in their feces
- Individuals who were methane producers
- Rarely had SRB detected in their feces
- Those with high concentrations of SRB
- Did not produce methane
- Methane status was determined by breath testing
- Negative results in individuals who carry methanogens in low concentrations
- Not conclusive in determining the presence of methanogens in the GIT
- 30 South African volunteers
- Cultured samples from methane-positive individuals
- Have lower rates of both sulfate-reduction and acetogenesis than those from methane-negative individuals
- Three distinct classes:
- Methanogenic, with no SRB detected in feces
- Methanogenic with low numbers of SRB detected in feces
- Non-methanogenic with high SRB counts in feces
- 87 individuals tested in this later study
- Only nine fell into the second class
- 41 the volunteers
- Methane-excreting and non-excreting groups - breath-testing
- All of the methane-excreting individuals harbored both methanogens and SRB, as did most of the non-excretors
- Methanogen-free group was in the minority in this study
- SRB cell counts differed significantly between methane-positive and negative individuals in their study cohort
- Negatively correlated with methanogen counts
- Every individual tested had detectable SRB in their feces, regardless of methane excretor status
- Methane and sulfide were both present in the flatus of their study subjects
- Significantly higher similarity in the microbiota composition of individuals from the same country than from different countries
- No significant relationship between
- Presence or abundance of methanogens and SRB was found by Hansen et al. when sequencing fecal samples from 68 sets of twins
- Find a significant relationship between the presence of methanogens and the abundance of several clusters within the Firmicutes phylum
- High hydrogen production of strains in these clusters
- Further possible variable affecting hydrogenotroph colonization.
- Methane-negative fecal samples
- Tended to contain a greater proportion of Gram-negative bacteria
- Methane positive samples
- Associated with more Gram-positive bacteria
- Greater hydrogen production by the Gram-positive Firmicutes
- Higher concentrations of available substrate for methanogens
- A negative correlation has been documented between acetogens and methanogens
- Perhaps there was some competition between
- Fecal samples from 106 Japanese individuals
- Unable to detect M. smithii in 92% of individuals
- Significantly lower methanogen colonization than was found in all eleven other countries
- Increased abundance of members of the genus Blautia
- Sulfate-reducing bacteria, by contrast, did not vary greatly between countries
- SRB counts did not vary widely between the individuals tested in their experiment
- When methanogens were chemically inhibited in fecal cultures from methane-producing individuals
- Total acetate production by the culture was threefold greater than that of the original fecal culture
- While methanogens competed effectively for hydrogen, acetogens were always present in these samples
- Obstipancia
- Increased methanogen counts
- Decreased SRB counts in feces
- Treatment with a laxative
- Opak:
- Slow growth rates of methanogens
- Reduced transit time negatively affects their population size
- Infusion of sulfated mucins to the model
- Methanogenesis was strongly inhibited
- Sulfide production increased dramatically
- SRB gene copies were higher than those of acetogenic bacteria in the proximal colon
- Opposite found in the distal colon
- Methanogenic genes varied most widely in quantity between sites and individuals
- From undetectable to 108 copies/g, with no clear pattern.
- Changes in dietary sulfate
- Transiently alter both methanogen and SRB population sizes
Poškození parasympatických nervů - n. vagus
Krční páteř blokáda
Blokáda zad
- V úrovni východzí inervace pro
- Ileockální chlopeň
- Motilitu tenkého střeva
Peristaltika tenkého střeve zpomalená
- řada možných příčin
Poškození tenkého střeva
- Např. při Crohnově chorobě, po operacích
