Surgical infection is a complex of diseases manifested as a result of the penetration of pathologically dangerous bacteria into the tissue after the operation. For such phenomena, the occurrence of a focus of inflammation and body reactions to foreign microorganisms is characteristic. Traditionally, modern medicine uses antibacterial therapy as a treatment and prevention of surgical infection. Nevertheless, there are situations when surgical intervention cannot be dispensed with, since many diseases are accompanied by purulent-septic complications.
Classification of surgical infection
The postoperative pathological process, having an infectious nature of development, is divided into acute and chronic. The first category includes:
- purulent;
- putrefactive;
- anaerobic;
- specific (such as tetanus, anthrax and diphtheria bacteria) infections.
The second category is:
- non-specific;
- specific (such as mycobacterium tuberculosis, bacteria syphilis, actinomycosis, etc.).
For surgical diseases accompanied by purulent processes, there are several classifications.
Etiological signs
In addition, surgical infections are pathologies that are divided according to etiological signs, namely:
By source of infection :
By the type of pathogen:
- staphylococcal;
- streptococcal;
- pneumococcal;
- colibacillary;
- gonococcal;
- anaerobic non-spore forming;
- clostridial anaerobic;
- mixed type.
By type of origin, there are surgical infections:
- nosocomial;
- community-acquired.
By type of pathology:
- diseases of infectious surgical origin;
- complications of diseases of infectious surgical origin;
- postoperative infectious complications;
- complications of an infectious nature with closed and open injuries.
According to the clinical course:
- in acute form;
- in chronic.
At the place of localization, various types of surgical infection can affect:
- skin and subcutaneous tissue;
- the brain and its membranes;
- neck structure;
- chest, pleural cavity, lungs;
- a complex of mediastinal organs;
- peritoneum and abdominal organs;
- pelvic organs;
- bones and joints.
The main pathogens
Surgical infection is, first of all, pathogens that cause a specific and non-specific course. Despite a wide variety of diseases caused by infectious pathogenesis, they have a lot in common.
Nonspecific infection
Most often occurs when certain varieties of pathogens enter the body tissue. In this case, the response of the body, despite the differences in the pathogen, will be similar, i.e. non-specific. In practice, such reactions are called purulent-inflammatory process. They can be caused by gram-positive and gram-negative, aerobic and anaerobic bacteria and pathogenic fungi. The most common pathogens that cause nonspecific surgical infections are:
- Staphilicoccus aureus (Staphylococcus) is a common microorganism that provokes the development of purulent-inflammatory processes. It exists in three varieties: golden, epidermal, saprophytic. The first variety is the most dangerous and refers to pathogenic microorganisms. Epidermal, saprophytic belong to non-pathogenic pathogens, but in recent years they are increasingly found in purulent-inflammatory diseases.
- Pseudomonas aeruginosa (Pseudomonas aeruginosa) - is normally determined on the skin and rarely causes purulent inflammation itself, but it easily joins the pathological microflora that has appeared. When it enters the focus of infection, the inflammatory process is delayed, since Pseudomonas aeruginosa is resistant to many antibiotics.
- Eisherichia coli (Escherichia coli) causes purulent-inflammatory pathologies of the tissues of the abdominal cavity (appendicitis, cholecystitis, peritonitis, abscesses, etc.).
- Enterococcus (Enterococci) - gram-positive cocci present in the microflora of the digestive system. In the presence of suitable conditions, purulent processes are caused.
- Enterobacter (entrerobacteria) - just like enterococci, live in the intestinal system. They can provoke a purulent-inflammatory pathological process.
- Streptococcus (Streptococcus) - There are about 20 species of this microorganism. When infected, they cause severe intoxication and a prolonged inflammatory process.
- Proteus vulgaris (Proteus) - gram-negative sticks, normally found in the mouth and intestines of a person. They are a dangerous nosocomial surgical infection. Under suitable conditions and in tandem with other pathogenic pathogens, they provoke the development of severe purulent inflammation. Resistant to many antibiotics.
- Pneumococcus (Pneumococcus) - is present in the microflora of the upper respiratory tract and nasopharynx. Promotes the development of pneumococcal peritonitis, abscess of the lung and brain.
- Bacteria belonging to the group of non-fermenting. They represent a whole group of heterogeneous aerobic and anaerobic surgical infections. They have a low pathogenicity, but under suitable conditions they provoke putrefactive inflammation.
Purulent diseases can be caused by a single pathogen (monoinfection) or several types of infections (mixed infection), which form a microbial association.
Cases when the inflammatory process is caused by several pathogens that exist in the same habitat (for example, aerobic) is called polyinfection. If microorganisms of different groups participate in the inflammatory process, then this is a mixed infection.
Specific surgical infection
In the first case, the pathological process is caused by certain microorganisms and leads to the appearance of foci of inflammation characteristic only for these bacteria. These include: fungal bacteria, actinomycetes, spirochetes, diphtheria corinobacteria, anthrax bacteria.
Pathogenesis
The development of surgical infectious diseases is determined by three main factors:
- Type of pathogenic microorganism and its properties.
- The place of penetration of bacteria (entrance gate).
- The reaction of the body to infection.
Determination of the properties of a pathogenic microorganism involves the detection of its virulence (pathogenicity), which is estimated by the minimum dose of bacteria that provoke the development of infection. These characteristics depend on their invasiveness (ability to overcome protective barriers and penetrate into tissues) and toxigenicity (ability to produce toxins that damage body tissues).
Properties of pathogenic microorganisms
Of course, depending on the variety of the strain and the presence of other pathogenic microorganisms, the pathogenic properties of the pathogen may vary. Therefore, mono-infections are much easier and easier to treat.
Surgical infections are significantly aggravated if secondary diseases join them, which often contribute to an increase in the activity of the primary pathogen. The quantitative factor is also important: the more pathogenic microorganisms penetrated the tissue, the higher the likelihood of a purulent-inflammatory disease.
Entrance gate
The first stage of the onset of the infectious process is the penetration of the pathogen into the tissue. This phenomenon is called infection and can be exogenous (pathogenic microorganisms penetrate the tissues from the outside, forming the primary focus of infection) and endogenous (activation of microbes already present in the body that did not previously pose a threat).
The skin and mucous membranes of the body are a barrier to infection. In cases of damage to their integrity or violation of the local protective mechanisms of the body, optimal conditions appear for pathogenic microflora to enter . The ducts of the sweat, sebaceous or mammary glands can become the entrance gate.
However, such an introduction does not always provoke an infectious process, since in most cases, bacteria die as a result of the action of immunity. Therefore, the likelihood of developing a pathogenic process depends on the site of the general surgical infection and the presence of favorable conditions.
Immune system condition
The general condition of the body often plays an important role. With a small infection with weak pathogenic indicators, with good protective reactions of the body, the pathological process can be quickly suppressed or not develop at all.
The general protective reaction is determined by non-specific reactivity (depends on individual resistance, genetic factors, tissue saturation with necessary trace elements) and the general state of immunity.
Specific mechanisms
Each organism has the ability to produce its own antibacterial substances that protect it from the effects of penetrated pathogens. Immune protection is provided by the production of antibodies of the humoral and cellular type. These substances in the body begin to be produced due to exposure to toxins and enzymes of pathogens, as well as their metabolic products and the breakdown products of their own tissues.
What reduces protection
In some cases, an organism that is attacked by pathogenic bacteria may have some functional disorders characteristic of concomitant pathologies. This makes it impossible to implement milestones of protective reactions, which creates favorable conditions for the development of infection.
Factors affecting the likelihood of developing an infectious disease include:
- Gender of the patient. The female body has more pronounced protective reactions, therefore it is more resistant to infectious diseases.
- Age group. Infectious diseases often affect children and older people.
- Chronic overwork.
- Poor nutrition and lack of vitamins. Nutrient deficiency significantly weakens the general state of immunity.
- Anemia. This disease significantly weakens the protective properties of the body, while with infectious diseases, anemia can rapidly develop against the background of the disease.
- Hypoglobulinemia, hypovolemia and a number of other pathologies. Contribute to the development of infection.
Many other conditions of the body, in which blood flow disorders (for example, diseases of the cardiovascular system), and immunodeficiency diseases (for example, diabetes mellitus) also contribute to the development of the disease.
The course of the pathogenic process
The infectious process is divided into stages: incubation, heat and recovery. At each of these periods, various processes occur both in the focus of inflammation and in the body as a whole. Changes that occur during the infectious process are divided into protective (resistance of the body) and pathological (destructive effects of the infection).
The starting point of the incubation phase is considered to be the moment of penetration of the pathogenic medium into the body, however, clinical manifestations of this process can appear only after some time (an average of about 6 hours).
The height of infection is the period from the end of the incubation phase to a complete cure. It manifests itself with a characteristic picture for a characteristic pathogen in combination with the protective ability of the body.
Reconvalescence (recovery) occurs after the provision of appropriate antibacterial care for surgical infection. As a result of adequate therapy, the activity of the infectious process subsides, the body recovers, eliminating the consequences and injuries provoked by the disease.
Symptoms
The general symptomatology of a surgical infection is manifested depending on the duration of the course of the disease and its stage. The incubation period is most often asymptomatic, only some infectious diseases can manifest as headache, weakness, etc.
During the height of the infection, clinical manifestations manifest themselves in the form of endogenous intoxication syndrome, since they are caused by exposure to microbial toxins and decay products of body tissues. Signs of this process are manifested in the form of: malaise, lethargy, weakness, insomnia, headache, fever, etc.
The clinical picture of the manifested symptoms is more pronounced in the purulent-necrotic stage than the serous-infiltrative one. In addition, the symptomatology depends on the severity of intoxication.