Staphylococcal infections

Staphylococcal infections are widespread anthropozoonotic bacterial infections with multiple mechanisms of transmission of the pathogen. Characterized by the development of purulent inflammation in the lesions, intoxication and the frequent generalization of the pathological process with the development of sepsis.

The diagnosis of staphylococcal infection is based on Gram stain and culture. Treatment of staphylococcal infection is carried out with protected beta-lactams, but because resistance to the latter is common, it may be necessary to use vancomycin. Some strains are resistant to all antibiotics. The exception in these cases is the newest antibiotic directed to the ribosome (eg, linezolid, quinupristin plus delfopristin) or lipopeptide antibiotics.

ICD-10 codes

• A05.0. Staphylococcal food poisoning.
• A41.0. Septicemia caused by Staphylococcus aureus.
• A41.1. Septicemia caused by another specified staphylococcus.
• A41.2. Septicemia caused by an unspecified staphylococcus.
• A48.3. Toxic shock syndrome.

What causes staphylococcal infection?

Infection is the infection of the body with microbes that can cause various diseases. In our case, we are talking about infection with staphylococci, which has its own peculiarities.

Staphylococcus is a representative of a conditionally pathogenic microflora. This suggests that the given bacterium is a constant companion of man, upholstered on his skin, mucous and even inside the body. Under normal conditions, when the body's defenses are at an altitude, staphylococcus can not bring tangible harm. Even if you get into an organism where there are all suitable conditions for reproduction, a bacterium can not lead to a disease if the immune system produces in sufficient quantity substances capable of supporting a conditionally pathogenic microflora in an inactive state.

In ordinary conditions, staphylococcus lives in the air and on the surface of the body. How can it get into the body? With dirty hands, with insufficiently disinfected tools (medical surgical instruments, catheters, intravenous systems, piercing and manicure devices, shaving accessories and many others), with unwashed food, saliva, etc. All the ways of spreading the infection (airborne, household and food) are equally relevant because of the large prevalence of staphylococcus in the environment.

Quite often, staphylococcal infection is observed in medical institutions. The reason is non-compliance with sanitary and hygienic requirements. Even when the skin before a prick or puncture for the purpose of blood sampling is cleaned with alcohol solution, this is done not so much because of dirt and dust, but because of bacteria such as staphylococcus, which are present on the body almost constantly. So, the risk of contracting this conditionally-pathogenic bacterium is always, if the skin is not cleaned enough.

Do not think that the activation of the bacterium occurs only when it enters the body through the blood or digestive tract. With weakened immunity, staphylococcal infection is dangerous even on the surface of the skin. It costs only a little to damage the skin, and bacteria will perceive this as a signal to action. So it is often the staphylococcus causes the purulent inflammatory processes on the skin.

Staphylococcus itself (microscopic round microorganism) is relatively harmless, even if it enters the body. Harm to the human body is caused by toxic products of its vital activity, which disrupt the metabolic processes in the cells, as a result of which local immunity decreases, and inflammation develops where there is a large accumulation of bacteria, i.e. Where they are actively multiplying.

With the bloodstream, staphylococcal infection can spread throughout the body, which leads to the emergence of many foci of inflammation and severe intoxication of the body. It is clear that leaving the disease without treatment is dangerous for life, but the treatment of the disease without destroying its pathogen is impossible. The most effective drugs against bacterial infection are antibiotics, and only applying them from staphylococcus can stop the spread of the disease.

What are the symptoms of staphylococcal infection?

Staphylococcal infection can manifest itself in various places of our body: on the skin, in the throat, nose, ears or eyes, on the internal organs. It is clear that the symptoms of the disease with different localization of the affected area will be different. A major role in the development of the clinical picture of pathology will be played by the species and strain of the pathogen, the age of the patient, and its immune status.

With skin infection, you can observe the appearance of various eruptions with purulent contents inside. When staphylococcus enters the body through the mouth, inflammatory pathologies of the tonsils, throat and mucous membranes of the mouth, as well as diseases of the respiratory system (bronchitis, pneumonia, pleurisy, etc.) or digestion (inflammatory bowel disease) can develop. Staphylococci in the nose will cause rhinitis, sinusitis and other pathologies of the nasal passages and adnexal sinuses, which can be complicated by inflammation of the middle and inner ear. But getting into the external auditory canal staphilococcus can cause a purulent-inflammatory lesion of the skin of the hearing organ. The spread of staphylococcus into the brain causes inflammation of the meninges, on the heart region - cardiac, and in parallel hitting small blood vessels.

We can say that there is no place in the body where staphylococcus can not be inherited when the immune system fails. And everywhere, where bacteria begin to multiply actively, an inflammatory or purulent-inflammatory focus is formed, and the organism is intoxicated with the products of the vital activity of bacteria. It is clear that when the infection spreads through the body, the symptoms of intoxication become more intense, which causes fever, nausea and vomiting, headaches, severe weakness and fatigue.

How is staphylococcal infection diagnosed?

diagnosis of staphylococcal infection is based on Gram stain and on the culture of the infected material. It is necessary to determine the sensitivity to antibiotics. This is due to the fact that methicillin-resistant staphylococci are often found today, and their detection requires alternative therapy.

Staphylococcal food poisoning should be suspected in case of group cases (for example, several family members, participants in social groups or restaurant customers). Confirmation of the staphylococcal nature of the disease (usually conducted by the health department) requires the isolation of staphylococci from suspected food, and sometimes of testing for enterotoxins.

Bone changes caused by osteomyelitis are not visible during X-ray examination for 10-14 days, and bone loss and periosteal reaction are imperceptible even longer. At an earlier time, bone changes can be detected with MPT, KT and radionuclide scanners.

How is Staphylococcal Infection Treated?

Despite the fact that the staphylococcal infection is on our body and even inside the body constantly, to treat it before the onset of symptoms of the disease does not make sense. A healthy strong organism is able to cope with microbes on its own. Assistance from the outside is needed only if the immune system is weakened, which makes it possible for bacteria to multiply unhindered, causing damage to various organs and tissues of a person.

When symptoms of a disease appear, a person turns to a therapist who, when suspected of an infection, should prescribe not only the usual clinical blood and urine tests, but also invite the patient to submit an analysis to the pathogen. This is a very important point, on which the effectiveness of the prescribed treatment largely depends.

We already know that evolution has affected not only people or animals, but also microorganisms. Over the long years of the existence of bacteria, many new species and strains have appeared that react differently to antimicrobial agents. Some strains of staphylococcal infection in the course of evolution have learned to synthesize substances that destroy active components of antibiotics, which significantly reduces the sensitivity of staphylococcus to antibiotics.

The ability of bacteria to reduce the effectiveness of antimicrobial agents is called antibiotic resistance. This problem scientists are trying to solve by creating new antibiotics with other properties. But this does not mean that in time, staphylococcus will not develop "immunity" to them. Moreover, to prevent the widespread use of antibiotics without prescribing a doctor, which contributes to the spread of the problem of antibiotic resistance, is very, very difficult.

People do not want to understand: what does not kill a bacterium makes it stronger. An unsuitable preparation or dosage will lead not to the destruction of the microorganism, but to its mutation, as a result of which it will receive new properties that make it resistant to antibiotics.

Well, with dosage everything is clear. And what is the wrong drug, because all antibiotics are designed to kill a bacterial infection? The fact is that infection is a general concept, because even several staphylococci exist. And not yet invented an antibiotic that equally well cope with any type of infection.

If the instructions to the drug carefully read information about its pharmacological properties, you can see a list of bacteria in the fight against which this antibiotic is particularly effective. Separately isolated microorganisms, which are partially sensitive to the drug, and those that can not be destroyed by this drug.

When prescribing antibiotics from staphylococcus, it is necessary to take into account the sensitivity of the detected strain to the prescribed drug. If a man has tonsillitis caused by golden Staphylococcus, there is no point in prescribing him a prescription for an antibiotic, inactive or not active at all with respect to this type of infection.

Very often, with staphylococcal infection, antibiotics of a wide spectrum of action are prescribed, because in addition to staphylococcus in the body, there may be other types of pathogenic bacteria. Yes, and besides these drugs can begin treatment, without waiting for the results of the analysis of the pathogen, which is very important in acute conditions.

Preference is usually given to beta-lactam antibiotics of the penicillin and cephalosporin series. It is them that we are used to treating almost all infectious diseases. But bacteria have already learned how to combat these antibiotics in a few years of their existence, so the effectiveness of these drugs is increasingly being questioned.

Some drugs are enhanced by the addition of beta-lactamase inhibitors (bate-lactamase, an enzyme produced by bacteria to reduce the effectiveness of beta-lactams from a series of penicillins and cephalosporins) into their composition, but even this does not make them all-powerful. After all, every day there are more and more new strains of staphylococcus, which need to be checked regularly for sensitivity to antibiotics.

How is staphylococcal infection prevented?

The purpose of preventive measures is to prevent the occurrence of staphylococcal infection in the home, at work; Staphylococcal food poisoning, nosocomial staphylococcal infection. To sanitize carriers and increase immunity to staphylococcal infection, immunized with purified, adsorbed staphylococcal a-toxin in pregnant women and patients subject to planned surgical intervention.

Aseptic precautions (eg thorough hand washing between patient studies and equipment sterilization) will help reduce the spread of staphylococcus in hospital settings. Strict isolation of procedures performed in patients with resistant microbes. Isolation of procedures in these patients should be carried out until the infectious process is healed. The asymptomatic nasal carrier does not need isolation, except when it is a carrier of MRSA or is suspected of spreading the infection. Such drugs as cloxacillin, dicloxacillin, trimethoprim-sulfamethoxazole, ciprofloxacin (each of these drugs are often combined with rifampicin), and topical mupirocin are effective for the treatment of carriers of MRSA, but in 50% of cases staphylococcus is restored and becomes resistant to the drugs by which elimination .

Prevention of staphylococcal food poisoning is the proper preparation of food. Patients with staphylococcal skin infections should not be allowed to cook. The food should be consumed after cooking or placed in the refrigerator. Do not store cooked food at room temperature.