Anaerobic infection – the infectious process caused by sporoobrazuyushchy or nesporoobrazuyushchy microorganisms in the conditions favorable for their activity. Prevalence of symptoms of endogenous intoxication over local manifestations, putrefactive character of exudate, gas-forming processes in a wound, quickly progressing necrosis of fabrics are characteristic clinical signs of an anaerobic infection. The anaerobic infection is distinguished on the basis of the clinical picture confirmed with results of microbiological diagnostics, a gas-liquid chromatography, mass spectrometry, an immunoelectrophoresis, PTsR, IFA, etc. Treatment of an anaerobic infection assumes radical surgical processing of the purulent center, intensive dezintoksikatsionny and antibacterial therapy.
Anaerobic infection – pathological process as which activators the anaerobic bacteria developing in the conditions of an anoxia (lack of oxygen) or a hypoxia (low voltage of oxygen) act. The anaerobic infection represents the severe form of infectious process which is followed by damage of vitals and high percent of a lethality. In clinical practice experts should face an anaerobic infection in the field of surgery, traumatology, pediatrics, a neyrokhirugiya, otolaryngology, stomatology, pulmonology, gynecology and other medical directions. The anaerobic infection can arise at patients of any age. The share of the diseases caused by an anaerobic infection is definitely not known; from the purulent centers in soft fabrics, bones or joints anaerobe bacterias are sowed approximately in 30% of cases; anaerobic bacteremia is confirmed in 2-5% of cases.
Reasons and characteristic of an anaerobic infection
Anaerobe bacterias are a part of normal microflora of skin, mucous membranes, digestive tract, bodies of urinogenital system and on the virulent properties are opportunistic. Under certain conditions they become causative agents of an endogenous anaerobic infection. Exogenous anaerobe bacterias are present at the soil and the decaying organic masses and cause pathological process at hit in a wound from the outside. Anaerobic microorganisms share on obligate and facultative: development and reproduction of obligate anaerobe bacterias is carried out in the oxygen-free environment; facultative anaerobe bacterias are capable to survive both in absence, and in the presence of oxygen. To facultative anaerobic bacteria colibacillus, shigellas, iyersiniya, streptococci, staphylococcus, etc. belong.
Obligate causative agents of an anaerobic infection are divided into two groups: sporoobrazuyushchy (klostridiya) and nesporoobrazuyushchy (neklostridialny) anaerobe bacterias (fuzobakteriya, bakteroida, veyllonella, propionibakteriya, peptostreptokokk, etc.). Sporoobrazuyushchy anaerobe bacterias are activators of klostridioz of an exogenous origin (tetanus, gas gangrene, botulism, food toksikoinfektion, etc.). Neklostridialny anaerobe bacterias in most cases cause pyoinflammatory processes of the endogenous nature (abscesses of internals, peritonitis, pneumonia, phlegmons of maxillofacial area, otitis, sepsis, etc.).
As major factors of pathogenicity of anaerobic microorganisms serve their quantity in the pathological center, biological properties of activators, existence of bacteria-assotsiantov. In pathogenesis of an anaerobic infection the leading role belongs to the enzymes produced by microorganisms, endo-and to ekzotoksina, nonspecific factors of metabolism. So, enzymes (a geparinaza, a gialuronidaza, a collagenase, a deoxyribonuclease) are capable to increase virulence of anaerobe bacterias, destruction of muscular and connecting fabrics. Endo - and ekzotoksina cause damage an endoteliya of vessels, intra vascular and thrombosis. Besides, some klostridialny tokisina possess nefrotropny, neyrotropny, kardiotropny action. Also toxic impact on an organism is exerted also by nonspecific factors of metabolism of anaerobe bacterias - an indole, fatty acids, hydrogen sulfide, ammonia.
The conditions favoring to development of an anaerobic infection are damage of anatomic barriers with penetration of anaerobe bacterias into fabrics and the blood course, and also decrease in oxidation-reduction potential of fabrics (ischemia, bleeding, a necrosis). Hit of anaerobe bacterias in fabric can happen at surgeries, invasive manipulations (punctures, a biopsy, extraction of tooth, etc.), perforation of internals, open injuries, wounds, burns, stings of animals, a syndrome of a long sdavleniye, criminal abortions etc. As the factors promoting developing of an anaerobic infection massive pollution of wounds by the earth, existence of foreign matters in a wound, gipovolemichesky and traumatic shock, associated diseases (collagenases, diabetes, tumors), an immunodeficiency act. Besides, the irrational antibiotic treatment directed to suppression of the accompanying aerobic microflora is of great importance.
Depending on localization distinguish an anaerobic infection:
- central nervous system (brain abscess, meningitis, subduralny empiyema, etc.)
- heads and necks (parodontalny abscess, Ludwig's quinsy, average otitis, sinusitis, neck phlegmon etc.)
- airways and pleura (aspiration pneumonia, abscess of a lung, empiyem of a pleura and so forth)
- female reproductive system (bartolinit, salpingit, adneksit, the endometritis, pelvioperitonit)
- abdominal cavity (abscess of an abdominal cavity, peritonitis)
- skin and soft fabrics (klostridialny cellulitis, gas gangrene, nekrotiziruyushchy fastsiit, abscesses, etc.)
- bones and joints (osteomyelitis, purulent arthritis)
Symptoms of an anaerobic infection
Irrespective of a type of the activator and localization of the center of an anaerobic infection, some common features are peculiar to various clinical forms. In most cases the anaerobic infection has the sharp beginning and is characterized by a combination of local and general symptoms. The incubatory period can make from several hours to several days (on average about 3 days).
Prevalence of symptoms of the general intoxication over the local inflammatory phenomena is a typical sign of an anaerobic infection. Sharp deterioration in the general condition of the patient usually occurs even before emergence of local symptoms. As display of heavy endotoxicosis serves high fever from oznoba, the expressed weakness, nausea, a headache, block. Are characteristic arterial hypotonia, , tachycardia, hemolytic anemia, an ikterichnost of skin and a skler, .
At a wound anaerobic infection the severe, accruing pain of the holding apart character, the emphysema and a krepitation of soft fabrics caused by gas-forming processes in a wound acts as an early local symptom. The fetid ichorous smell of exudate connected with release of nitrogen, hydrogen and methane at anaerobic oxidation of a proteinaceous substratum is among constant signs. Exudate has a liquid consistence, serous and hemorrhagic, is purulent - hemorrhagic or purulent character, non-uniform coloring with impregnations of fat and existence of vials of gas. Also points out appearance of the wound containing fabrics of gray-green or gray-brown color, sometimes strupa of black color putrefactive character of an inflammation.
The course of an anaerobic infection can be lightning (within 1 days from the moment of operation or a trauma), sharp (within 3-4 days), subsharp (more than 4 days). The anaerobic infection often is followed by development of polyorgan insufficiency (kidney, hepatic, warm and pulmonary), the infectious and toxic shock, heavy sepsis which are the reason of a lethal outcome.
Diagnosis of an anaerobic infection
The correct assessment of clinical symptoms allowing to provide in due time necessary medical care is of great importance for timely diagnosis of an anaerobic infection. Depending on localization of the infectious center clinical physicians of various specialties – the general surgeons, traumatologists, neurosurgeons, gynecologists, otolaryngologists, maxillofacial and thoracic surgeons can be engaged in diagnostics and treatment of an anaerobic infection.
Methods of express diagnosis of an anaerobic infection include a bacterioscopy of the wound dab separated with coloring on Gram and a gas-liquid chromatography. In verification of the activator the leading role belongs to bacteriological crops separated a wound or contents of abscess, to the analysis of pleural liquid, crops of blood on aerobic and anaerobic bacteria, to an immunofermental anayoliz, PTsR. In biochemical indicators of blood at an anaerobic infection decrease in concentration of proteins, increase in level of creatinine, urea, bilirubin, activity and alkaline phosphatase is found. Along with clinical and laboratory researches, the X-ray analysis at which the gas congestion in the struck fabrics or cavities is found is carried out.
The anaerobic infection needs to be differentiated from an erysipelatous inflammation of soft fabrics, a polymorphic ekssudativny eritema, thrombosis of deep veins, pheumothorax, a pnevmoperitoneum, perforation of hollow abdominal organs.
Treatment of an anaerobic infection
An integrated approach to treatment of an anaerobic infection assumes carrying out radical surgical processing of the purulent center, intensive dezintoksikatsionny and antibacterial therapy. The surgical stage has to be executed as soon as possible – the patient's life depends on it. As a rule, it consists in a wide section of the center of defeat with removal of nekrotizirovanny fabrics, decompressions of surrounding fabrics, open drainage with washing of cavities and wounds solutions of anti-septic tanks. Features of a course of an anaerobic infection quite often demand carrying out repeated nekrektomiya, disclosure of purulent pockets, processing of wounds ultrasound and the laser, ozonoterapiya etc. At extensive destruction of fabrics amputation or an exarticulation of an extremity can be shown.
The most important components of treatment of an anaerobic infection are intensive infusional therapy and antibiotic treatment by medicines of a broad spectrum of activity, vysokotropny to anaerobe bacterias. Within complex treatment of an anaerobic infection hyperbaric oxygenation, UFOK, extracorporal haemo correction find the application (haemo sorption, a plasma exchange, etc.). If necessary to the patient anti-toxic antigangrenous serum is entered.
Forecast and prevention of an anaerobic infection
The outcome of an anaerobic infection in many respects depends on a clinical form of pathological process, a premorbidny background, timeliness of establishment of the diagnosis and an initiation of treatment. Lethality level at some forms of an anaerobic infection exceeds 20%. Prevention of an anaerobic infection consists in timely and adequate PHO of wounds, removal of foreign matters of soft fabrics, observance of requirements of an asepsis and antiseptics when carrying out operations. At extensive wound damages and high risk of development of an anaerobic infection carrying out specific immunization and antimicrobic prevention is necessary.