endocarditis
Introduction
Introduction to endocarditis Endocarditis (infective endocarditis) is an inflammatory disease caused by direct invasion of the endocardium by pathogenic microorganisms, often involving the heart valve, but also involving the ventricular septal defect, the endocardial intima or the patent ductus arteriosus Venous fistula and so on. Endocarditis can be caused by bacteria, mold, rickettsia, and viruses. There are three main types of symptoms in the clinic, namely systemic infection symptoms, cardiac symptoms, embolism and vascular symptoms. It is also the most common and most important systemic symptom with fever. basic knowledge The proportion of illness: the incidence rate is about 0.004% - 0.007% Susceptible people: no special people Mode of infection: non-infectious Complications: renal abscess pericarditis cerebral embolism
Cause
Endocarditis cause
The factors that cause endocardial infection are:
Inhibition of defense mechanisms (35%):
For example, tumor patients use cytotoxic drugs and immunosuppressive agents for organ transplant patients. The causes include various bacteria, fungi, and coxiella burnettii. Clinically, it is related to pathogenic microorganisms. Traditionally, it is divided into acute and subacute. The clinical and pathological changes are different. Acute infective endocarditis is also known as ulcerative endocarditis because it is often ulcerated by the endocardium. This type of endocarditis has a sharp onset, mostly caused by virulence of septic bacteria (acute bacterial endocarditis), most of which are Staphylococcus aureus, followed by Streptococcus pyogenes. Usually the pathogen causes suppurative inflammation (such as suppurative osteomyelitis, sputum, sputum fever, etc.) in a certain part of the body. When the body's resistance is reduced (such as tumor, heart surgery, immunosuppression, etc.), the pathogen invades the bloodstream, causing Sepsis and invasion of the endocardium. This type of endocarditis occurs mostly on the normal endocardium, which infringes the aortic valve alone or invades the mitral valve.
Pathogen infection (35%):
Inflammation of the heart valve or ventricular wall is caused by direct infection of bacteria, fungi and other microorganisms (such as viruses, rickettsia, chlamydia, spirochetes, etc.), which is different from rheumatic fever, rheumatoid, systemic lupus erythematosus Non-infectious endocarditis caused by etc.
Prevention
Endocarditis prevention
1. Patients with severe valvular injury require valve repair or replacement. Therefore, prevention of infective endocarditis is extremely important.
2. Rheumatic valvular disease or congenital heart disease should pay attention to oral hygiene, timely treatment of various infections, antibiotics should be given before surgery or equipment examination, prevention of endocarditis often occurs about two weeks after surgery.
Measures to prevent infection in patients with predisposing factors during surgery or operation:
(1) Oral upper respiratory tract operations or surgery should be given antibiotics against Streptococcus mutans.
(2) Urogenital and digestive system surgery or operators should be used for enterococci.
Complication
Endocarditis complications Complications, renal abscess, pericarditis, cerebral embolism
The disease can have the following complications:
1, the heart:
(1) Congestive heart failure is the most common complication; valvular perforation and chordae rupture lead to acute heart failure;
(2) Myocardial abscess is common in acute can cause conduction block;
(3) Most of the acute myocardial infarction is caused by coronary artery embolism with aortic valve infection;
(4) suppurative pericarditis;
(5) Myocarditis.
2, bacterial aneurysm: more common in the subacute affected artery followed by the proximal aortic brain viscera and limbs.
3, metastatic abscess: acute IE more common subacute is rarely seen in the liver and spleen bones and nervous system.
4, the nervous system:
(1) Cerebral embolism accounts for half of the middle cerebral artery and its branches are most susceptible;
(2) Brain bacterial aneurysms are asymptomatic unless ruptured;
(3) cerebral hemorrhage is caused by cerebral embolism or bacterial aneurysm rupture;
(4) toxic encephalopathy may have meningeal irritation;
(5) Brain abscess;
(6) Septic meningitis is not common after the three are mainly seen in acute IE, especially Staphylococcus aureus endocarditis.
5. Kidney: Most patients have kidney damage including:
(1) renal embolism and renal infarction;
(2) focal and diffuse glomerulonephritis caused by immune complexes, the latter can cause renal failure is common in subacute IE;
(3) Kidney abscess: rare.
Symptom
Endocardial symptoms Common symptoms Fatigue loss of appetite, pulmonary embolism, night sweats, heart murmur, persistent fever, hemiplegia
The onset is slow and the symptoms are varied. Most patients have structural heart disease, and some patients have a history of dental caries, tonsillitis, venous intubation, interventional therapy, or intracardiac surgery.
1. Symptoms of infection; fever is the most common symptom. Almost all cases have had different degrees of fever, irregular heat type, long heat history, and no fever in individual cases. In addition, the patient has fatigue, night sweats, loss of appetite, weight loss, joint pain, pale skin and other symptoms, the disease progresses slowly.
2. Symptoms of the heart: The original heart murmur can be changed by the neoplasm of the heart valve, and there is a rough, loud, seagull-like or musical noise. Musical murmurs may occur in patients without heart murmurs. About half of children suffer from congestive heart failure due to heart valve disease, toxic myocarditis, etc., and heart sounds are blunt and galloping.
3. Embolism symptoms; different clinical manifestations depending on the location of the embolization, generally occurred in the late stage of the disease, but about 1/3 of the patients are the first symptoms. Skin embolism can be seen in scattered small defects, the toe flexion can have a raised purple red nodule, slightly tender, this is the Euclidean knot; visceral embolism can cause splenomegaly, abdominal pain, hematuria, blood in the stool, sometimes splenomegaly Very significant; pulmonary embolism can have chest pain, cough, hemoptysis and lung snoring; cerebral arterial embolism is headache, vomiting, hemiplegia, aphasia, convulsions and even coma. For a long time, the clubbing and toe can be seen, but there is no cyanosis.
At the same time, there are not many typical patients with the above three symptoms. In particular, infants under 2 years old are mainly affected by systemic infection symptoms, and only a few children have embolic symptoms and/or heart murmurs.
Examine
Endocarditis examination
1, blood test: common blood picture is progressive anemia, mostly positive cell anemia and leukocytosis, neutrophils increased. ESR increased, C-reactive protein was positive. When combined with immune complex-mediated glomerulonephritis, severe heart failure or hypoxia-induced erythrocytosis, serum globulin often increases, and even the ratio of albumin and globulin is inverted. The immunoglobulin is elevated, the -globulin is elevated, the circulating immune complex is increased, and the rheumatoid factor is positive.
2, blood culture: blood bacterial culture positive is an important basis for the diagnosis of infective endocarditis, where the cause of unexplained fever, body temperature lasted for more than 1 week, and the original heart disease, should actively and repeatedly carry out blood culture In order to increase the positive rate, if the blood culture is positive, the drug sensitivity test should be done.
3, urine test: urine has red blood cells, proteinuria can occur during fever.
4. Electrocardiogram: Because the myocardium can have multiple pathological changes at the same time, fatal ventricular arrhythmia may occur. Atrial fibrillation suggests atrioventricular valve regurgitation. Complete atrioventricular block, right bundle branch block, left anterior or posterior branch block have been reported, suggesting that myocardial suppuration or inflammatory response is aggravated.
5. Echocardiography: Echocardiography can detect sputum organisms larger than 2mm in diameter, so it is helpful for the diagnosis of infective endocarditis. In addition, echocardiography can dynamically observe the size of sputum during treatment. Morphology, activity, and valve function status, to understand the degree of valve damage, have reference value for determining whether to do valve replacement surgery. The test can also reveal the original heart disease.
6, CT examination: For suspected intracranial lesions should be done in time to understand the extent of the lesion.
Diagnosis
Diagnosis and differentiation of endocarditis
Differential diagnosis
1, febrile diseases, such as fever as the main manifestation, need to be differentiated from typhoid, sepsis, tuberculosis, rheumatic fever and systemic lupus erythematosus.
2, heart failure, with heart failure as the main performance with low fever or no fever, should be differentiated from heart disease with heart failure.
3, rheumatic myocarditis, active rheumatic myocarditis and the identification of this disease is more difficult, because both can have fever, anemia, increased erythrocyte sedimentation rate and heart damage, but if there are embolism, splenomegaly, hematuria, clubbing and Positive blood culture, especially two-dimensional echocardiography found that there are large neoplasms, support the diagnosis of infective endocarditis.
4, left atrial myxoma, sometimes this disease and left atrial myxoma is not easy to identify, but infective endocarditis in children with neoplasms in the left atrium is rare.
5, endocarditis after surgery, need to be identified with the following two diseases:
(1) Pericardial incision syndrome: occurs several days to several weeks after heart surgery with a happy bag, showing fever, chest pain, pericardial cavity and/or pleural effusion, leukocytosis, increased erythrocyte sedimentation rate, and sometimes pericardium Filling, need to be pericardial puncture to drain the effusion. This disease is a self-limiting disease, effective as oral aspirin or hormone.
(2) Postoperative perfusion syndrome: more than 3 to 6 weeks after cardiopulmonary bypass, clinical manifestations of fever, anorexia, hepatosplenomegaly, pleural effusion and atypical lymphocytosis. This disease is caused by the contamination of giant cell inclusion body virus during blood use during surgery, and it is also a self-limiting disease. The treatment is the same as the pericardial incision syndrome.
