Bacterial endocarditis( BE) is a severe inflammatory disease of the heart valves with unfavorable prognosis and the formation of persistent complications affecting the patient's quality of life in the future.
Is an independent disease unlike other endocarditis, developing as a manifestation or complication of other diseases.
Features and causes of
Pathogens BEare : Staphylococcus aureus, enterococci, green streptococcus, betta-hemolytic streptococcus, Escherichia coli, Pseudomonas aeruginosapoints, pathogenic fungi.
The occurrence of bacterial endocarditis is always preceded by intervention or manipulation, which can lead to the ingress of microorganisms into the blood flow:
- intravenous spray and drip administration of medicines;
- removal of tonsils, adenoids;
- dental procedures, including tooth extraction;
- any surgical interventions;
- medical manipulations in which microbes can be introduced: bronchoscopy( examination of the respiratory tract), cystoscopy( examination of the bladder), catheterization of the urethra, abortion, etc.;
- Injecting drug use.
In response to the antigens of the pathogen in the bloodstream, antibodies are formed, resulting in the flow of toxic immune complexes into the blood. Their effects trigger hypersensitivity reactions. Therefore, for the development of the disease requires a combination of two factors:
- bacteremia - circulating in the blood of the causative agent of the infection;
- autoimmune process - sensitization of the organism to the pathogen.
As a result of bacteremia , pathogens reach the heart valves and can attach to the endothelium of the , especially if there are damages to the heart valves or thrombotic overlays that become an excellent springboard for the deposition of microbes. At the attachment site, an infectious focus arises, the consequence of which is the destruction of the valve and its ulceration.
As microorganisms infect the most commonly damaged heart valves, factors predispose to the development of bacterial endocarditis:
- Scars on the heart valves after rheumatic fever;
- Congenital heart defects: open oval aperture, heart defect of tetralogy of Fallot, abnormal development of interventricular septum, etc.;
- Acquired defects: aortic or mitral valve defect;
- Calcification of valves due to atherosclerosis;
- Cardiomyopathy;
- Artificial heart valve;
- Mitral valve prolapse;
- Marfan syndrome( hereditary autosomal disease);Endocarditis in the anamnesis.
Classification
- By the presence or absence of a background disease:
-
Primary - develops on intact( undamaged) valves, the second name is Chernoburov's disease( since he first described this type of BE in 1949).
occurs in 20 to 30% of cases. In the last decade, the frequency of primary EB development has become much higher.
- Secondary - occurs on altered( vicious) valves. This type of BE is observed in 70 - 80% of cases. It develops against the background of rheumatic heart disease, less often against the background of syphilitic, atherosclerotic, congenital or acquired defects.
- Subacute : the main pathogens of the disease - green streptococcus, epidermal staphylococcus, diphtheria bacteria. The cause of bacteremia is often asymptomatic infections of the mouth, urogenital system or digestive tract. In most cases it develops on the affected valves. The onset of the disease is gradual, the patients find it difficult to name the time of the onset of the first symptoms. The disease can be preceded by tooth extraction, tonsillectomy, abortion, etc.
- Acute : the dominant causative agent is staphylococcus aureus. The disease is preceded by a purulent infection( meningitis, septic thrombophlebitis, etc.).Can develop on intact valves.
- Artificial valve BA : develops in patients after prosthetic valve apparatus, mainly during the first year after surgery. It occurs in 2-3% of cases.
- BE of the right heart of the : typical for injecting drug users. The causative agent enters the venous blood stream and affects the right side of the heart. The main reason is non-observance of the rules of antiseptics, since even when using disposable syringes, drug addicts often do not disinfect the skin at the injection site, therefore microorganisms from the skin surface are inserted into the blood with a needle.
- 1 place - left atrioventricular.
- 2 place - aortic valve.
- 3rd place - right atrioventricular.
- 4th place - the valve of the pulmonary trunk.
Clinical picture: symptoms and signs
Common symptoms are caused by the infectious process, their severity depends on the type of pathogen:
- fever: temperature 38,5 - 39,5 ºC with two peaks during the day;
- chills, profuse sweating, especially at night;
- tachycardia, associated with both a rise in temperature and with heart failure;
- shortness of breath;
- pallor of the skin, with severe skin, the skin may be pale gray with icteric shade( coffee color with milk);
- weakness, rapid fatigue, a constant sense of fatigue;
- loss of appetite, weight loss;
- joint and muscle pain;
- hemorrhagic eruptions on mucous and skin integuments.
Also characteristic are the characteristic peripheral features of of bacterial endocarditis:
- Lukin-Liebman Spots - petechial rashes on the oral mucosa, conjunctiva and folds of the eyelids;
- Osler Nodes - cherry-red thickening on hands and feet;
- Drum fingers - the terminal phalanges of the fingers look like a drumsticks, nails - watch glasses;
- Jainuei Spots - hemorrhages in the skin and subcutaneous fatty tissue prone to ulceration;
- Rota spots - hemorrhages in the retina with a pale spot in the center.
For , the thromboembolic syndrome , i.e., the onset of emboli, is characteristic. Depending on where the detached blood clot will be carried away by the blood stream, symptoms of damage to the relevant organs will occur.
Embolism can cause pain in the chest due to a heart attack or myocarditis, kidney damage in the form of hematuria, glomerulonephritis, etc., pain in the upper and lower extremities and paralysis, sudden loss of vision, cerebral circulation disorders due to brain ischemia, headache, abdominal pain, myocardial infarction, kidney, spleen, lung, etc.
When palpation of , an increase in the spleen( splenomegaly) and liver ( hepatomegaly) is often observed.
At auscultation, hears the pronounced noises in the heart of due to thrombotic overlap. Later, there are signs of heart failure as manifestations of the valve apparatus formed during the disease.
In case of lesion of the right heart, in addition to general symptoms,
- chest pains are observed;
- hemoptysis;
- lung infarction.
Diagnosis
A typical clinical picture - when several signs of bacterial endocarditis are detected, the diagnosis usually does not cause difficulty .So, for example, the presence of fever, enlarged spleen, skin hemorrhagic eruptions, hematuria combined with heart murmurs indicate the infection process occurring in it.
- Laboratory diagnostics:
-
Changes in blood tests : leukocytosis with neutrophilia, increased ESR, possible reduction of hemoglobin, increase of serum immunoglobulin content, detection of circulating immune complexes in the blood.
To clarify the pathogen make a blood culture.
- Changes in urinalysis : hematuria is blood in the urine, proteinuria is a protein in the urine.
- Electrocardiography( ECG);
- Echocardiography;
- Magnetic resonance and computed tomography( MRI and CT).
Tactics of treatment
Treatment is carried out only in a 24-hour hospital.
Etiotropic
The basis of treatment is antibacterial therapy .First, when establishing the diagnosis, antibiotics of a wide spectrum are appointed, after determining the causative agent in the blood culture analysis, therapy is adjusted with the appointment of the most sensitive drug. If the pathogen is not identified, then the clinical situation is analyzed with the identification of the most probable pathogen and re-seeding.
For the therapy of bacterial endocarditis , long-term administration of large doses of antibiotics is required becauseinfectious processes on the valves of the heart are difficult to treat.
Drugs of choice:
- antibiotics of the penicillin series;
- cephalosporins;
- fluoroquinolones;
- vancomycin.
Symptomatic
- Hypocoagulation: administration of heparin in combination with plasma.
- Immunomodulatory therapy: hyperimmune plasma, human immunoglobulin is used.
- Inhibition of proteolytic enzymes.
- Detoxification therapy.
Surgical
If the conservative therapy is ineffective, surgical treatment is indicated for the removal of intracardiac foci of infection with subsequent prosthesis of the valvular apparatus.
Danger and consequences
Bacterial endocarditis is a very dangerous disease, in the absence of timely qualified treatment can provoke serious complications of on the part of many organs and systems:
- Heart : myocardial infarction, valve flaws, arrhythmias;
- Nervous system : meningitis, circulatory disorders of the brain, paresis and paralysis of the upper and lower extremities;
- Light : pneumonia, abscess, edema, heart attack;
- Spleen : infarction, splenomegaly;
- Liver : hepatitis, hepatomegaly( enlargement of the liver);
- Kidney : nephritis, heart attack, kidney failure;
- Vascular system : thrombosis, thromboembolism, thrombophlebitis, vasculitis, aneurysm.
This is far from an incomplete list of possible complications, they are all very heavy and can significantly affect the quality of life of the patient. Therefore, is of great importance for early diagnosis and immediate treatment with antibacterial drugs.
Learn more about bacterial endocarditis from this video:
Forecasts
Forecast of bacterial endocarditis conditionally unfavorable .Before the introduction of a wide range of antibacterial drugs into practice, the disease in most cases ended in a fatal outcome.
To date, due to effective treatment, lethality decreased to 30% .Death can occur as a result of cardiac, renal failure, thromboembolism, or other serious complications.
A favorable outcome is possible with early potent antibiotic therapy combined with comprehensive symptomatic treatment. In this case, significantly increases the chances of recovery( with the formation of residual sclerotic changes in valves of different degrees of severity).
The recurrence of is possible if the antibiotic therapy is inadequate or insufficient. In this case, surgical treatment is indicated to avoid complications.
Symptoms of bacterial endocarditis after 6 weeks after treatment with indicate the onset of a new infectious process.
Prevention measures
- Timely sanation of foci of infection;
- Treatment of chronic inflammatory diseases of bacterial nature;
- Observance of special safety measures in patients with heart defects( and other patients at risk):
- mandatory treatment of intercurrent( joined) diseases;
- long-term administration of antibiotics in the emergence or exacerbation of tonsillitis, pneumonia, pyelonephritis, sore throat and in any surgical interventions;
- preventive prescription of antibiotics before any interventions in which bacteremia is possible( tooth extraction, abortion, bronchoscopy, cystoscopy, etc.).
Bacterial endocarditis is a serious dangerous disease, like most heart pathologies. Therefore, in order to avoid all consequences and complications, is better to be actively involved in prevention, to apply for qualified medical care in a timely manner and not to engage in self-medication. Take care of yourself and your heart!