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Anaerobic infections
Anaerobic infections - infectious process caused by spore-forming microorganisms or Non-spore under conditions favorable for their livelihoods. Typical clinical signs of anaerobic infections are the prevalence of symptoms of endogenous intoxication over local manifestations, putrid nature of the exudate, gas-forming processes in the wound, rapidly progressive tissue necrosis. Anaerobic infection antibiotics definition is detected on the basis of clinical, confirmed by the results of microbiological diagnostics, gas chromatography, mass spectrometry, immuno PCR, ELISA, and others. Treatment of anaerobic infections requires a radical surgical treatment of purulent focus, intense detoxication and antibacterial therapy.
Anaerobic infection - disease process, which are the causative agents of anaerobic bacteria, developing in conditions of anoxia (lack of oxygen) or hypoxia (low oxygen tension). Anaerobic infection is a severe form of the infection process, accompanied by the defeat of the vital organs, and a high percentage of mortality. In clinical practice, with anaerobic infection faced by professionals in the field of surgery, traumatology, pediatrics, neyrohirugii, otolaryngology, dentistry, pulmonology, gynecology and other medical fields. Anaerobic infection may occur in patients of any age. The proportion of diseases caused by anaerobic infection, is not exactly known; of purulent lesions in soft tissues, bones or joints anaerobes sown approximately 30% of cases; anaerobic bacteremia confirmed in 2-5% of cases.
Anaerobes are part of the normal flora of the skin, mucous membranes, gastrointestinal tract, urogenital system and its virulent properties are opportunistic. Under certain conditions, they become agents of endogenous anaerobic infections. Exogenous anaerobes are present in soil and decaying organic masses and cause a pathological process when released into the wound from the outside. Anaerobic bacteria are divided into obligate and facultative: development and reproduction obligate anaerobes carried out in an oxygen-free environment; facultative anaerobes are able to survive both in the absence and in the presence of oxygen. To belong to facultative anaerobic bacteria E. coli, Shigella, Yersinia, streptococci, staphylococci, and others.
Obligate pathogens anaerobic infections are divided into two groups: spore (clostridia) and asporogenous (non-clostridial) anaerobes (fuzobakterii, Bacteroides, veyllonelly, propionibacteria, peptostreptokokki et al.). Spore-forming anaerobes are the pathogens klostridiozov exogenous origin (tetanus, gas gangrene, botulism, food poisoning, etc.). Non-clostridial anaerobes in most cases cause purulent inflammation of the endogenous nature (visceral abscesses, peritonitis, pneumonia, cellulitis maxillofacial region, otitis media, sepsis, and others.).
The main factors of pathogenic anaerobic microorganisms are their number in the pathological focus, the biological properties of pathogens, the presence of bacteria-Assiociants. In the pathogenesis of anaerobic infections leading role belongs to the enzymes produced by microorganisms, endo- and exotoxins, nonspecific metabolic factors. Thus, the enzymes (heparinase, hyaluronidase, collagenase, DNase) can enhance the virulence of anaerobic bacteria, destruction of muscle and connective tissue. Endo- and exotoxins cause damage to the vascular endothelium, intravascular hemolysis and thrombosis. In addition, some clostridial tokisiny have nephrotropic, neurotropic, kardiotropnoe effect. Also toxic effects on the body and have non-specific factors anaerobic metabolism - indole, fatty acids, hydrogen sulfide, ammonia.
Conditions conducive to the development of anaerobic infections are damaged anatomical barriers to the penetration of anaerobes in the tissues and bloodstream, as well as reduction of the redox potential of tissue (ischemia, hemorrhage, necrosis). Contact anaerobes in the tissue can occur during surgery, invasive procedures (punctures, biopsies, tooth extraction, etc.), Perforation of internal organs, open injuries, wounds, burns, animal bites, syndrome of prolonged compression of, criminal abortion, and so on. D. Factors contributing to the emergence of anaerobic infections, wounds are the massive pollution of land, the presence of foreign bodies in the wound, hypovolemic and traumatic shock, concomitant diseases (collagen diseases, diabetes, cancer), immunodeficiency. In addition, great importance is inappropriate antibiotic therapy aimed at suppressing the concomitant aerobic microflora.
Regardless of the type of pathogen and localizing the anaerobic infections, various clinical forms has certain features in common. In most cases, anaerobic infection has an acute onset and is characterized by a combination of local and general symptoms. The incubation period may be from several hours to several days (on average about 3 days).
A typical feature is the predominance of anaerobic infections symptoms of intoxication on the local inflammatory phenomena. The sharp deterioration in the general condition of the patient usually begins before the appearance of local symptoms. A manifestation of severe endotoxemia is high fever with chills, severe weakness, nausea, headache, lethargy. Characterized by hypotension, tachypnea, tachycardia, hemolytic anemia, ikterichnost skin and sclera, akrotsianoz.
When wound anaerobic infections early local symptom appears strong, increasing pain Expander nature, emphysema and crepitus soft tissue caused by gas-forming processes in the wound. Some of the signs include persistent fetid odor ihoroznym exudate associated with the release of nitrogen, hydrogen and methane from the anaerobic oxidation of the protein substrate. The fluid has a liquid consistency, serous-hemorrhagic, purulent and hemorrhagic or purulent, non-uniform color with splashes of fat and the presence of gas bubbles. On the putrid nature of the inflammation also indicates the appearance of wounds containing tissue gray-green or gray-brown, sometimes black crusts.
Flow anaerobic infections can be fulminant (within 1 day after surgery or injury), acute (within 3-4 days), subacute (more than 4 days). Anaerobic infection is often accompanied by the development of multiple organ failure (kidney, liver, heart-lung), infectious-toxic shock, severe sepsis, which are the cause of death.
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