Clinical manifestations of subacute infective endocarditis

 Clinical manifestations of subacute infective endocarditis

[clinical manifestations of subacute infective endocarditis]

Most cases have slow onset, low fever, fatigue and fatigue, and a few have acute onset, chills, high fever or embolism. Some patients have a history of oral surgery, respiratory infection, abortion or delivery before onset.

1、 Fever caused by systemic infection is the most common, often with unexplained continuous fever for more than a week, irregular low fever, mostly between 37.5 ℃ - 39 ℃, intermittent fever or relaxation fever, accompanied by fatigue, night sweat, progressive anemia, splenomegaly, and clubbing fingers in the late stage.

2、 The heart shows inherent signs of heart disease. Due to the growth or fall off of vegetations, the destruction of valves and tendons, murmurs are changeable, or new murmurs appear. If there is no murmur, endocarditis can not be excluded, and heart failure can occur in the late stage. When the infection affects the atrioventricular bundle or septum, it can cause atrioventricular block and bundle branch block. Arrhythmia is rare, and there can be premature beat or atrial fibrillation.

3、 Embolism and vascular lesions

（1） Skin and mucosal lesions are caused by rupture, bleeding, or micro embolism caused by the action of infectious toxins on capillaries to increase their brittleness. Ecchymosis can appear in batches on the skin, eye alkali binding membrane and oral mucosa of the limbs, purple or red Osler nodules slightly higher than the surface can appear on the palmar surface of the fingers and toes, or small nodular bleeding spots (Janeway nodules) can appear on the palms or feet without tenderness.

（2） Cerebrovascular lesions can have the following manifestations:

① Meningoencephalitis is similar to tuberculous meningitis, with increased cerebrospinal fluid pressure, increased protein and leukocyte counts, and normal chloride or sugar quantification. ② Intracerebral hemorrhage has persistent headache or meningeal irritation, which is caused by rupture of bacterial aneurysm. ③ Patients with cerebral embolism have fever, sudden paralysis or blindness. ④ Central retinal embolism can cause sudden blindness.

（3） Renal embolism is the most common, accounting for about 1 / 2 of the cases. There is gross or microscopic hematuria and severe renal insufficiency. After bacterial infection, antigen antibody complexes are deposited in renal blood vessels, resulting in renal vascular glomerulonephritis.

（4） Pulmonary embolism is common in cases of congenital heart disease complicated with infective endocarditis. Vegetations are mostly located on the intimal surface of the right ventricle or pulmonary artery, with acute onset, chest pain, dyspnea, hemoptysis, cyanosis or shock. If the infarct area is small, there may be no obvious symptoms.

In addition, there may be coronary artery embolism, manifested as acute infarction, splenic embolism, left upper abdominal pain or left costal pain, fever and local friction sound. Mesenteric artery embolism, manifested as acute abdomen, bloody stool, etc. Limb arterial embolism can include embolism, limb pallor and chills, weakening or disappearance of arterial pulsation, limb ischemia and pain, etc.

[laboratory and other inspections]

1、 Positive blood culture can determine the diagnosis and provide a basis for the selection of antibiotics. In order to provide the positive rate of culture, the following points should be paid attention to: ① before the application of antibiotics, culture continuously for 4-6 times. ② 10ml blood was drawn each time, and aerobic and anaerobic culture were performed at the same time. ③ The training time should be long, no less than three weeks. ④ If the culture result is positive, drug sensitivity test should be carried out.

2、 The hemogram showed progressive anemia, and the white blood cell count was normal or increased.

3、 ESR increased rapidly

4、 There are proteinuria and hematuria in routine urine, and about 1 / 3 of advanced patients have renal insufficiency.

5、 Echocardiography showed that there were vegetations in the heart valve or endocardial wall and abnormal manifestations of inherent heart disease.