Медицина /2.Хирургия

V. Patraboy, I. Herasymyuk, Abduraheem Issa,

M. Gumenna, D. Rotar

Bukovinian state medical university, department of microbiology and virusology, Ukraine

Dynamics and consequences of elimination of the indigenous intestinal microflora during acute destructive pancreatitis

Diseases of digestive system (Gastrointestinal tract): acute intestinal infections, chronic gastroenterocolitis, hepatitis, gastric and duodenal ulcer, cholecystitis, dyskinesia of biliary tract, irritable bowel syndrome are accompanied by the development of the syndrome of intestinal dysbiosis[1.75-86; 2.211-216]. Composition of microbiota of the gastrointestinal tract in patients with acute pancreatitis has not been studied, though these data may shed light on the pathological process in the pancreas and mechanism of bacterial contamination. The dominant microorganisms in the colon of intact animals at the population level (PL), quantitative domination ratio (efficiency) and index of significance (IS) is Bacteroides, aerobic grampositive Streptobacillus, Lactobacillum and Bifidobacterium. A lower (<100.0 efficiency) position is occupied by Eubacterium, Enterococcus, Escherichia coli, and Fuzobacterium, Prevotella (efficiency = 50,0-100,0) [3.220-230]. Other microorganisms (Peptococcus, Peptostreptococcus, bacteria genus Clostridium, Staphylococcus) don’t play a special role in microbiocenosis of colon cavity in healthy animals. These microorganisms are associated with dominant and leading bacteria, forming colon microbiota. Their growth and reproduction were inhibited by antagonistically active obligate autochthonous microorganisms. After 24 hours from the time of simulation of acute destructive pancreatitis (ADP) significantly (by 3 orders of magnitude) was decreased PL of Bifidobacterium, Lactobacillus (2 orders of magnitude), Bacteroides (almost 2 orders of magnitude), Prevotella (2 orders of magnitude), Eubacterium (more than 3 orders), Fuzobacterium (by 4 orders) Peptococcus (2 orders of magnitude) and Enterococcus (2 orders of magnitude). During this period, pathogenic and opportunistic Enterobacteria and Clostridium growing population level was raising (by 4 orders of magnitude), Escherichia coli (2 orders of magnitude), concentration of proteus and Staphylococcus was stable.

As a result, imbalance between members of the intestinal microflora of the colon causes domination of Bacteroides and E. coli for PL, efficiency and IS; leading microorganisms are Bifidobacteria, Lactobacilli, aerobic grampositive Streptobacillus which are dominant in intact animals, and Staphylococcus, Prevotella, Peptococcus and Clostridium. At this stage of the study, pathogenic and conditionally pathogenic enterobacteria play a role of associated microflora,which growth and reproduction suppress growth of dominant and leading bacteria of the microbiota of the colon at this stage.

In the next study period (48 h) there is a further reduction of PL of Bifidobacteria, Lactobacilli, the elimination of Enterococcus, Eubacterium, and aerobic gram-positive Fuzobacterium, Streptobacillus, significantly increased PL of pathogenic (enteropathogenic E. coli) and opportunistic (Edvarsiella, Escherichia coli, Klebsiella and Proteus) Enterobacteria, Clostridium in all experimental animals. PL of Bacteroides, Prevotella, Peptococcus, which was lower than rates in intact animals, it was stabilized and corresponds to the data that formed after 24 hours from the time of modeling ADP.

After 72 hours of researching of colon microbiota, a pronounced deficit of autochthonous obligate Bifidobacterium, Lactobacillus, Bacteroides, Prevotella, Peptococcus, and elimination of colon Eubacterium, Fuzobacterium, Enterococcus and aerobic Streptobacillus were present. However, PL of opportunistic pathogenic enterobacteria, peptostreptococci, clostridia and staphylococci increased.

In the next study period (after 96 and 120 h) PL of autochthonous obligate bacteria was decreased to minimum level in 42.9% of the animals, at the rest they were eliminated. In general, autochthonous obligate bacteria were eliminated from cavity of colon or they persisted in a minor (minimum level that defines from the method) PL. These changes increased the PR of opportunistic bacteria of the genus Clostridium, Escherichia coli, Staphylococcus and Proteus. Lowering of PL normal flora promotes colon contamination by pathogenic and opportunistic pathogenic Enterobacterium, Peptococcus, Peptostreptococcus and other microorganisms.

All this leads that the domination of Bacteroides, Peptococcus in the colon experimental ADP, E. coli; leading role in cavity microbiota is occupied by colon bacteria genus Clostridium, pathogens (enterotoxic Escherichia) and opportunistic pathogens (Klebsiella, Edvarsiella, Proteus) Enterobacteria and Staphylococcus. Physiologically helpful obligate indigenous Bifidobacterium, Lactobacillus are minor and Fuzobacterium, Enterococcus, aerobic grampositive Eubacteria and Streptobacillus were not detected in any animal.

Thus, the development and progress experimental ADP in rats is accompanied to the profound changes in composition of species, and especially the PL of each taxon, forming cavity colon microbiota. These changes depend on the duration (period) of ADP progress - increasing the progress of ADP causes deepening the relationship between changes associated microflora that form microbiocenosis of cavity colon.

Microorganisms belonging in intact animals autochthonous to obligate and usually take place in the dominant microbiota cavity colon at ADP has 24 hours of constancy index and, especially, PL decreases. These microorganisms include Bifidobacterium, Lactobacillus, Eubacterium, Fuzobacterium, Enterococcus and aerobic grampositive Streptobacillus. On the other hand, increased PL opportunistic E. coli and reaches high numbers (3-4 orders of magnitude), Peptococcus, bacteria of the genus Clostridium and Staphylococcus.

Microorganisms that in intact animals are autochthonous and occupy the dominant position in cavity microbiota of the colon, in 24 hours of ADP their constancy index and, especially, PL were decreased. These microorganisms include Bifidobacterium, Lactobacillus, Eubacterium, Fuzobacterium, Enterococcus and aerobic grampositive Streptobacillus. On the other hand,was increased PL of opportunistic E. coli (3-4 orders of magnitude), Peptococcus, bacteria of the genus Clostridium and Staphylococcus.

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