Rheumatic fever in children

Introduction to rheumatic fever in children Rheumatic fever (rheumaticfever) is one of the major diseases in pediatrics that endangers the life and health of school-age children. The lesion is a non-suppurative inflammation of systemic connective tissue, mainly invading the heart and joints, and other organs such as the brain, skin, and serosa. Blood vessels, etc. can be affected, but the heart damage is the most serious and common. Sometimes the first episode can damage the heart, and repeated episodes can cause two-thirds of the sick children to have chronic heart valve disease. basic knowledge The proportion of children: the incidence rate of children is about 0.03%--0.05% Susceptible people: children Mode of infection: non-infectious Complications: heart failure

Causes of rheumatic fever in children

Streptococcal infection (35%):

At present, most people think that the onset of rheumatic fever is due to the immune response caused by streptococcal infection. Streptococcal cell components and extracellular products are highly antigenic and specific. When humans are infected with streptococcus, specific antibodies are produced. These antibodies and antigenic substances are present. Degeneration and lysis in connective tissue. If there are more antibodies after streptococcal infection, the chance of rheumatic fever is higher. The ASO or other streptococcal antibody titers in patients with rheumatic fever are more common than uncomplicated streptococcal infection. There are many patients, which also supports the view that the immune response is the pathogenesis.

Genetic factors (25%):

Recently, genetic markers have been found in patients with rheumatic fever. A serum containing 883 B cell alloantigen (allogeneicantigen) was used, and approximately 72% of patients with rheumatic fever were positive.

Viral infection (20%):

In recent years, scholars have paid more attention to the theory of viral infection, and believe that rheumatic fever may be related to Coxsackie B3, B4 virus infection.

Immune function (10%):

Changes in immune function status may also be involved in the occurrence of rheumatic fever.

Pathogenesis

Pathogenesis

(1) Streptococcal infection and immune response theory: Although the etiology and pathogenesis of rheumatic fever have not been fully elucidated so far, it is currently recognized that rheumatic fever is caused by autoimmune diseases of group A streptococcus infection after pharyngeal infection. Some structures of human tissue and streptococcus have cross-antigenicity, so the body can mistakenly think that streptococci are "autologous", and do not produce a normal immune response to remove it. Once the body's immune function changes, streptococcus as an antigen Entering the human body can produce corresponding antibodies, and various autoantibodies such as anti-myocardial antibodies, anti-M protein antibodies, anti-cardiac valve polysaccharide antibodies, anti-neuron antibodies, etc. have been detected, and such antibodies not only react with streptococcus-related antigens. At the same time, it can also act on the relevant antigens of the myocardium, heart valve, nerve tissue and connective tissue, causing autoimmune reaction, leading to the corresponding tissue damage, causing the occurrence of rheumatic fever. During the development of rheumatic fever, the cellular immune mechanism is also Play an important role, through immunohistochemical techniques, confirmed that the rheumatic fever lesions infiltrated with T lymphocytes Patients with rheumatic fever have enhanced lymphocyte response and a series of cellular immune response markers, such as interleukin (IL-1, IL-2), tumor necrosis factor-gamma (TNF-), and enhanced white blood cell migration inhibition. Natural killer cells (NK) and monocyte cytotoxicity are increased, T lymphocytes are enhanced by streptococcal antigens, phagocytic cells produce free radicals, and procoagulant activity in peripheral blood and heart tissue cells are increased, indicating that cellular immunity is in rheumatic fever. It plays an important role in the pathogenesis.

(2) Virus infection theory: In recent years, relevant scholars have paid more attention to the theory of viral infection, and believe that rheumatic fever may be related to Coxsackie B3 and B4 virus infection. The basis is:

1 Coxsackie B3, B4 antibody titer was significantly elevated in the serum of some patients with rheumatic heart disease.

2 Rheumatic heart disease patients have found scorpion virus on the left atrium and heart valve.

3 When the Javanese monkey is infected with the Coxsackie B4 virus, it can produce pathological changes similar to rheumatic heart disease, but this theory has not been generally accepted, and it is difficult to explain that penicillin does have a significant effect on preventing recurrence of rheumatic fever. Many scholars believe that viral infection May create conditions for streptococcal infection, and play an incentive role in the occurrence of rheumatic fever.

(3) Genetic factors: Recently, there are genetic markers in patients with rheumatic fever. A serum containing 883 B cell alloantigen (allogeneicantigen) is used. About 72% of patients with rheumatic fever are positive, and the same species for B cells. The antigen has also produced monoclonal antibody D8/17, 80% to 100% of patients with acute rheumatic fever, while the control group is only 15% positive, so it is possible to use monoclonal antibodies to screen acute rheumatic fever susceptible populations. Genetic studies have found that patients with rheumatic fever and their relatives have specific antigen expression on the cells of the immune system. Most reports have an increased frequency of HLA-DR4, and some sites of HLA-DQAl and DQB1 have increased frequency. The progress of this research may find rheumatic fever and easy patients in the majority of people to carry out targeted prevention and treatment. Most scholars believe that genetic factors can be used as one of the risk factors, but the incidence of multiple members in the same family, the most likely cause It is still related to the same living environment and easy to infect each other.

(4) Immune function: Changes in immune function may also be involved in the occurrence of rheumatic fever. Immunoglobulin IgG, IgA and IgM are often elevated during rheumatic fever and rheumatism; although leukocytosis is elevated in blood, phagocytosis is reduced. The lymphocyte transformation test results showed that the lymphocyte conversion rate to the original lymphocytes decreased, indicating that there is a defect in cellular immune function, and in addition, the cell-mediated immune response is also important in the course of the disease.

As for the theory of malnutrition, the relationship between trace elements and rheumatic fever (currently found to be closely related to the immunopathological mechanism of zinc deficiency and rheumatic fever and rheumatic heart disease), endocrine disorders, etc., continue to explore, in short, the pathogenesis of rheumatic fever Intricate, it is the result of a combination of factors such as streptococcal pharyngeal infection and immune status.

2. Pathology

Rheumatic fever is a systemic connective tissue inflammation that can be divided into three phases depending on the course of the lesion.

(1) Denatured exudation period: Collagen fibers in connective tissue divide, swell, form glassy and cellulose-like degeneration, and there are lymphocytes, plasma cells, eosinophils, neutrophils and other inflammatory cells around the degenerative lesions. Infiltration, this period can last for 1 to 2 months, and resume or enter the second and third phases.

(2) Proliferative phase: Rheumatoid granuloma or Aschoff body appears on the basis of the above lesions, which is a characteristic lesion of rheumatic fever, which is the basis for pathological diagnosis of rheumatic fever and an indicator of rheumatic activity. There is cellulose-like necrosis in the center of the body, lymphocytes and plasma cells infiltrated at the edge, and rheumatoid cells. The rheumatoid cells are round, elliptical or polygonal, and the cytoplasm is rich in basophilic, nucleus empty, with obvious Nucleolus, sometimes occurs in the formation of giant cells in the form of dinuclear or multinuclear, and enters the hardening phase, which lasts for 3 to 4 months.

(3) Hardening period: The degeneration and necrotic substances in the center of the rheumatoid body are gradually absorbed, the inflammatory cells exuded are reduced, the fibrous tissue is proliferated, and scar tissue is formed in the granuloma.

Because the disease often recurs, the development of the above three phases can be staggered, it takes 4 to 6 months, the first phase and the second phase are often accompanied by serous exudation and inflammatory cell infiltration, this exudative lesion is To a large extent, it determines the occurrence of various clinical symptoms. The pathological changes in joints and pericardium are mainly exudative, while the formation of scars is mainly limited to the endocardium and myocardium, especially the valve.

The inflammatory lesions of rheumatic fever involve collagen fibers in the connective tissue of the whole body. In the early stage, the joints and the heart are involved, and then the heart damage is dominant. The lesions in each stage are concentrated in the affected organs, such as exudation in the joints and pericardium. , the formation of arthritis and pericarditis, after the exudate can be completely absorbed, a few pericardial exudate absorption is incomplete, polarization forms part of the adhesion, in the myocardium and endocardium is mainly proliferative lesions, after the formation of scar proliferation, heart valve Proliferative lesions and adhesions often lead to chronic rheumatic valvular disease.

Pediatric rheumatic fever prevention

The prevention of rheumatic fever can be divided into two types: prevention of initial attack and recurrence. After the initial infection of group A hemolytic streptococcus, the incidence of rheumatic fever is about 1, and early detection of streptococcus is difficult, so it is difficult to prevent the first episode of rheumatic fever. At the time of treatment, only patients with confirmed streptococcal infection were treated with early penicillin. Patients with rheumatic fever were prone to recurrence after streptococcal infection. The recurrence rate of rheumatic fever in the first 3 years after the first episode was about 75%. To aggravate heart damage, it is important to prevent streptococcal infection from preventing recurrence of rheumatic fever. The prevention method is as follows.

1. Prevention of the first episode

Upper respiratory tract group A -hemolytic streptococcal infection such as scarlet fever, tonsillitis, pharyngitis is the cause of rheumatic fever, so prevention of primary rheumatic fever must be paid attention to, and appropriate treatment, due to the clinical manifestations of group A virus can also be Other bacteria cause it necessary to make a good pharyngeal culture before treatment. At this time, almost all of the group A streptococci growth positive results, such as the first pharyngeal culture negative, and clinically suspected of streptococcal infection, A second pharyngeal culture should be done.

In order to prevent the onset of primary rheumatic fever, the treatment of streptococcal infection should begin immediately after the determination of streptococcal infection:

1 intramuscular injection of benzathine penicillin G, body weight of 25kg, 1.2 million units, intramuscular injection 1 time.

2 or 400,000 units of intramuscular penicillin, 2 times a day for a total of 10 days.

3 If you are allergic to penicillin, you can use erythromycin 30mg/kg/d, no more than 1g per day for 10 days. Sulfonamides are only effective for preventing recurrence and are not used to treat streptococcal infection.

2. Prevention of recurrence

In people with rheumatic fever, if the upper respiratory tract infection occurs, the risk of recurrence of rheumatic fever is very high. Whether or not there are obvious symptoms, it can cause recurrence. Even if the symptomatic infection is actively treated, prevention may fail. Therefore, Preventing the recurrence of rheumatic fever is more successful than continuous preventive measures, rather than relying on the treatment of acute streptococcal pharyngitis, so those who have had rheumatic fever, have chorea, and rheumatic carditis should Give long-term continuous preventive measures.

The precautions are as follows:

1 intramuscular injection of benzathine penicillin G 1.2 million units, bone injection once every 4 weeks.

2 or oral penicillin V, 2 times a day, each time 250,000 units, but oral is not easy to adhere, the child must cooperate very well, can be used for children with low recurrence.

3 people who are allergic to penicillin can take sulfadiazine or erythromycin, sulfadiazine 1.0g, once a day, such as weight <25kg, 0.5g each time, once a day, erythromycin 0.25g, 2 times a day.

The effect of intramuscular injection of benzathine penicillin G is better. According to the pediatrics of Shanghai First Medical College, the recurrence rate of patients with rheumatic fever is 6 times higher. The preventive effect of penicillin is better than that of sulfonamide. It is extended to adulthood, and penicillin or other application is applied. Streptococcal infection can sometimes occur during the recurrence of rheumatoid fever. The clinical manifestations are only fever and sore throat. The throat swab culture is mostly negative. At this time, penicillin or other anti-streptococcus drugs should be added.

Rheumatic fever complications in children Complications heart failure

Heart failure, rheumatic heart valve disease and other complications can be seen.

Heart failure

Heart failure caused by acute rheumatic fever is often caused by acute rheumatic carditis, especially in younger patients.

2. Rheumatic heart valve disease

75% to 80% of rheumatic fever complicated with rheumatic valvular heart disease, endocarditis of rheumatic carditis mainly involves heart valves, inflamed valve congestion, swelling and thickening, small neoplasms appear on the surface, forming a valve closure Incomplete, fibrin deposition at the leaflet closure can cause adhesion of the leaflets, changes in the leaflets plus adhesion and shortening of the chordae and papillary muscles, deforming the heart valve, resulting in stenosis and regurgitation of the valve orifice, forming rheumatic Heart valve disease.

Rheumatic fever symptoms in children Common symptoms Lack of lymph nodes, sore throat, rheumatoid arthritis, high fever, intercostal neuralgia, fever, joint swelling, pain, low heat, muscle pain, pericardial effusion

1 to 3 weeks before the onset of symptoms, there may be a history of short-term fever or scarlet fever such as pharyngitis, tonsillitis, cold, mild or severe symptoms, asymptomatic, pharyngeal symptoms usually disappear in about 4 days, no discomfort in the future After 1 to 3 weeks, it began to open the door, rheumatoid arthritis is often an acute onset, and carditis can be occult.

First, the general symptoms

The child is weak, tired, loss of appetite, pale, sweaty, nosebleed, and sometimes abdominal pain, which can be misdiagnosed as acute appendicitis, fever is generally not high and the heat type is irregular, a few can see short-term high fever Most of them continue to have low fever for a long time and last about 3 to 4 weeks.

Second, heart symptoms

According to the statistics of pathology, the heart of almost all cases has different degrees of involvement, while in children with rheumatic fever, heart disease is particularly prominent, and the heart muscle, myocardium and pericardium can be damaged, called rheumatic carditis or whole heart disease. The most important manifestation of rheumatic fever in children, from the clinical analysis of hospitalized children with rheumatic fever in Beijing Children's Hospital, 73.2% of cases have clinical manifestations of carditis, severe carditis can be followed by rheumatic heart valve disease, now according to acute rheumatism Carditis and chronic rheumatic valvular disease:

Acute wind and temperature carditis

(1) Myocarditis: There are different degrees of lesions in the myocardium of all children with rheumatic fever. Clinical manifestations of myocarditis are also common, and mild symptoms are not many, such as mild heart rate acceleration or short electrocardiogram. Slight changes, severe cases of diffuse myocarditis, clinical symptoms are obvious, often with heart failure, the following signs can occur when myocardial involvement.

1 heart rate is accelerated, 110 to 120 beats / min or more, and is not proportional to the height of body temperature.

2 heart sounds weakened, the first heart sound of the apex is low and blunt, sometimes running gallop.

3 abnormal heart rhythm can occur before the contraction, varying degrees of atrioventricular block, especially the first most common, a small number of complete atrioventricular block, causing A-S syndrome, other forms of arrhythmia Occasionally, the ECG can still show QT interval prolongation and T wave abnormalities.

4 The heart is mild or significantly enlarged.

(2) Myocarditis: The mitral valve is most commonly involved, followed by the aortic valve, and the apex has a full-systolic murmur of grade II to III, sometimes with a high pitch, such as a seagull, a murmur to the armpit and the left back. Conduction, respiration and body position have no effect on the murmur. This murmur indicates mitral regurgitation. About half of the apex can be accompanied by II to III mid-diastolic murmur (carey-coolmbs), due to rapid filling of the left ventricular diastolic or apical The relatively narrow stenosis caused by the stenosis of the valve is generally not seen in the acute phase of the mitral valve area. It does not necessarily mean that the valve has undergone irreversible organic damage. The murmur of the mild carditis disease is associated with valvular inflammation, edema, and platelet spasm. Related to the production of organisms, after the acute phase of inflammation, about half of the sick children's murmurs can disappear, but if the acute phase has passed, the condition is obviously improved, the murmur does not weaken or disappear, and the possibility of mitral regurgitation or stenosis will occur in the future. Greatly, in the aortic valve auscultation area, if you hear diastolic murmur, it has important pathological significance and generally rarely disappears.

(3) pericarditis: severe cases of children with pericarditis symptoms, and more with myocarditis and endocarditis, children with paroxysmal pain, sitting breathing and obvious breathing difficulties, early in the bottom of the heart or the left sternal border You can hear the pericardial rubbing sound. When a large number of pericardial effusions are auscultated, the heart sound is far away. The chest X-ray shows that the heart beat beats weakened or disappeared. The heart shadow expands to the sides and is in the shape of a flask. When lying, the heart and waist are widened. At the same time, the shadow of the waist is narrowed, which is differentiated from the enlargement of the heart. The acute phase of the ECG can have ST segment rise, QRS low voltage, T wave inversion later, ST segment decline, echocardiography between the posterior wall of the left ventricle and the pericardium An anechoic zone appears.

When acute rheumatic heart disease occurs, the heart muscle, endocardium and pericardium are often involved at the same time. It is difficult to distinguish which symptoms and signs are caused by myocarditis, endocarditis or pericarditis. It is called rheumatic heart. Inflammation or whole heart inflammation, 70% of carditis occurs within 2 weeks of the onset of the disease, a few can be delayed until 6 months, the heart enlarges in severe carditis, especially with heart failure, leaving more chronic valvular disease.

2. Chronic heart valve disease

Recurrent rheumatic fever and long duration (1/2 to 2 years), can cause scars on the valve or chordae due to the repair process of inflammatory lesions and also reduce the organic valve damage, becoming an inactive chronic rheumatic heart At the stage of valvular disease, rheumatic heart disease, which has the most chance of mitral valve injury, accounting for 3/4 of valvular disease, followed by aortic valve, accounting for 1/4, and some reported up to 1/2 (alone Occurred or with mitral valve disease), mitral and aortic valve damage accounted for more than 90% of cases of rheumatic valvular disease, tricuspid valve and pulmonary valve are rarely affected, and generally not damaged alone, in addition It should be pointed out that in childhood, rheumatic heart disease often has rheumatic activity in the presence of heart failure, which is very different from adult rheumatic valvular disease. In the acute phase, a small part of the mitral valve involvement can return to normal. In 30 to 60% of cases, permanent valvular lesions are left behind, and once the aortic valve is damaged, there is little chance of returning to normal.

(1) mitral regurgitation: the general symptoms are not obvious, the heavier children with reduced blood output, can feel fatigue, fatigue and heartbeat, when there is pulmonary blood stasis, difficulty breathing after exertion, heart The examination mainly refers to the systolic murmur of grade III or above in the apex of the apex. The murmur is characterized by perforation or at least to the mid-systole, conduction to the ankle, and sometimes accompanied by systolic tremor. The heart sound is normal or weakened, the second heart sound can be clearly split, and the obvious third heart sound can be heard. When the mitral regurgitation is closed, the left ventricular enlargement can cause functional apical diastolic middle murmur, cardiac X-ray examination. Show left atrium and left ventricle enlargement, sometimes visible systolic expansion of the left atrium, pulmonary vascular texture is normal, ECG can show left ventricular hypertrophy and mitral valve P wave, echocardiography examination of left atrial enlargement, C concave Deepening, the EF slope is increased, the mitral valve opening is increased, the E peak is high, and the left ventricular overload is performed: the left ventricle is enlarged, the left ventricular outflow tract is widened, and the ventricular septal left ventricular surface activity is increased.

(2) mitral stenosis: rheumatic endocarditis mitral stenosis generally requires a course of at least two years or more, most of which takes about 10 years, when the mitral annulus area is normal At half time, clinical symptoms begin to appear. Many patients with mild or moderate mitral stenosis may have obvious signs and are asymptomatic. The child is prone to fatigue, guilty, and gradually presents with shortness of breath. Caused by intense physical activity, emotional agitation, respiratory infection, atrial fibrillation, etc., the cheeks and lips are often purple-red ("mitral valve face"), severe patients with cough, may have thin, pink foam or hemoptysis , the performance of left heart failure such as sitting breathing, with right heart failure, systemic congestion, hepatomegaly, tenderness, ascites can occur in the late stage, 30% of adult cases can occur atrial fibrillation, prolonged formation of wall thrombus, can occur throughout the body Sexual embolism, physical examination found mainly in the apex of a sputum-like diastolic middle and late murmur, often accompanied by diastolic tremor, the first heart sounds hyperthyroidism, the second sound of the pulmonary artery also hyperthyroidism, in the left sternum Sometimes an open sound is heard below the edge, the pulse pressure is low, and the pulse is fine.

X-ray examination showed that the heart was enlarged, and the right atrium was mainly enlarged in the left atrium. There was also pulmonary artery bulging and pulmonary sputum. The upper and lower stenosis of the electrocardiogram could be right-sided deviation of the electrocardiogram, right ventricular hypertrophy, and P wave widening sometimes. Increased, atrial fibrillation may occur with carditis or a longer course of disease. Atrial fibrillation in children often indicates the presence of active rheumatic lesions. Echocardiographic examination of typical mitral stenosis changes to a decrease in EF slope, before mitral regurgitation Square or wall-like changes, the posterior lobe of the mitral valve and the anterior lobe of the mitral valve move in the same direction, the amplitude of the anterior mitral valve is low, the echo of the mitral valve is thickened, the left atrium is enlarged, and the mitral stenosis is combined with the mitral valve. When the closure is incomplete, if the lesions are prominent in the former, the anterior mitral valvular anterior diastolic rapid decline, the E peak can be seen, followed by a slow descending flat section, forming a "horseback" change.

(3) Aortic regurgitation: Aortic valve damage caused by rheumatic endocarditis is characterized by a longer period of cardiac compensation when the aortic regurgitation is closed, and the left ventricle is compensated without pulmonary congestion. Asymptomatic, so mild or moderate patients have no obvious symptoms, heavier patients have palpitations, carotid pulsation is obvious (arterial pulsation is obvious in all parts of the body), and some children can not take the left lateral position, because the left lateral position The strong pulsation makes the left chest discomfort, sweating, etc., left ventricular decompensation causes left ventricular dysfunction, sometimes the patient has angina pectoris, more often after a night of sleep, pale skin, palpitations, blood pressure rise at the beginning of the attack , breathing acceleration, etc., hair flushing after sweating, sweating, angina often can cause sudden death, when left heart failure, pulmonary congestion symptoms, pulmonary edema, sitting breathing, and finally cause right heart failure, physical examination: general In the second auscultation area of the aortic valve, that is, between the 3, 4 ribs of the left sternal border, a tone can be heard compared with the sputum of the sputum, and the early and middle murmurs can be heard in the right second intercostal space. Chest pieces most likely to hear more clearly when inhaling and sitting forward, aortic second heart sound weakened or disappeared, often strengthened when the aortic pressure increased, patients often have severe third heart sound.

In addition, there is often a jet systolic murmur in the aortic valve area, and a late diastolic murmur (Austin-Flint murmur) can be heard at the apex of the apex, such as a mitral valve such as a stenosis, which may be before the systole. In the middle of diastole or both, due to functional mitral stenosis, the chest percussion heart increases to the lower left, apical beats are enhanced, and is elevated. Other clinical features are due to aortic valve closure. Peripheral vascular signs, such as increased pulse pressure, water impulses and capillary pulsations, arterial sounds (Duroziez murmurs, systolic and diastolic murmurs heard in the femoral artery or other peripheral arteries), de Musset sign ( Due to the strong pulsation of the carotid artery caused by the rhythmic swing of the head), the Hill's sign (the aortic inversion of Wenerya, the systolic pressure difference of the femoral artery and the iliac artery sometimes reaches 60 ~ 100mmHg), etc., X-ray examination shows left ventricular enlargement Large and moderate cases have obvious left ventricular enlargement, and the left ventricle is extended downward into a shoe-shaped heart. The fluoroscopy of the aorta and left ventricle is enhanced under fluoroscopy. The electrocardiogram is normal or shows left ventricular hypertrophy. If there is mitral regurgitation Incomplete, there may be left atrial enlargement, right ventricular enlargement and pulmonary congestion. Echocardiographic examination of the aorta can not be closed into a line in diastolic, forming two echoes, the distance between the two echoes is >1 mm, sometimes visible on the closed line. There is fine tremor, the aortic valve opening and closing rate is accelerated, and the anterior mitral valve has diastolic fine tremor.

Second, mitral regurgitation often coincides with mitral stenosis, mitral regurgitation alone is common and unit mitral stenosis is rarely seen, aortic regurgitation often exists alone, generally more congenital, the main Inflammatory endocarditis is easy to occur in patients with incomplete arterial disease.

Third, arthritis

It is characterized by migratory and multiple nature. It is mainly composed of knees, ankles, wrists, elbows and other large joints. The small joints can be affected at the same time. Local redness, swelling, heat and pain usually disappear in a few days or weeks. Leftover deformity, light only joint pain, often accompanied by fever and increased erythrocyte sedimentation rate. In recent years, joint pain and severe pain have been extremely rare. People with typical arthritis, the heart is not tired, and joint pain often occurs with inflammatory disease. Therefore, joint pain is of great significance in diagnosis.

Fourth, chorea

It is characterized by varying degrees of irregular, involuntary movements. The typical symptoms are involuntary movements in the whole body or part of the muscles. The movements of the limbs are the most, the objects cannot be held, the buttons cannot be unbuttoned, and even the tongue is hyperactive. Eating, seriously affecting daily life, can cause singular and language barriers due to facial muscle twitching, and can also appear frowning, towering, closing eyes, shrugging and necking, most of the above actions are bilateral, or limited to one side, Increased in excitement or concentration, disappeared after falling asleep, muscle strength and infection are often barrier-free, age is more common after 6 years old, 8-12 years old is more common, after puberty is greatly reduced, girls are more than boys Most of the choreas appear 2 to 6 months after streptococcal infection. The general course of disease is 1 to 3 months. Sometimes it can be recurred. Occasionally, the chorea is one of the main manifestations of rheumatic fever. Exist, no carditis or chronic rheumatic valvular disease, or coexist with other symptoms of rheumatic fever, but at the same time in children with arthritis, about 25% of chorea patients can eventually develop carditis, when chorea alone As no heat, erythrocyte sedimentation rate, or slightly faster, most anti-streptolysin O in the normal range, also other related auxiliary examination of unremarkable.

Five, skin lesions

Subcutaneous summary

It is a symptom of rheumatic fever. It is generally a round nodule of pea size. It can be bulged on the skin, has no adhesion to the skin, can move freely, and has no tenderness. Individual large diameters can reach 1-2 cm, and the number varies. From a few to dozens, it is common in the elbow, wrist, knee, ankle and other joints of the sacral sheath attachment, but also on the scalp or the side of the spine, sometimes symmetrically distributed, the knot may exist for several days to several months When it disappears, it usually disappears after 2 to 4 weeks. Subcutaneous nodules often coexist with carditis, often appearing several weeks after onset. It is a prominent sign of rheumatic activity, which has been rare in recent years. Its incidence is about 1% to 4%, subcutaneous nodules are not specific symptoms of rheumatic fever, can be found in rheumatoid arthritis.

2. Ring erythema

Skin exudative lesions can cause urticaria, purpura, maculopapular rash, erythema multiforme, nodular erythema and ring erythema. Among them, ring erythema has the most diagnostic significance, characteristic of rheumatic fever, ring erythema The rate is about 10%, usually occurs when rheumatic fever recurs, often accompanied by carditis, more common in the trunk and four sides of the flexion, ring or semi-annular, slightly raised at the edges, pale rose, no pain and itching The skin color in the ring is normal. This kind of erythema often shows obvious after rubbing. It can be hidden in 1 day, leaving no desquamation and pigmentation. Ring erythema can appear intermittently, sometimes unbalanced with rheumatism.

Pneumonia and pleurisy

Less common, multiple non-specific exudative changes, mostly with severe carditis.

Pediatric rheumatic fever check

1. Test to reflect recent streptococcal infection and related immunity

(1) Determination of anti-streptolysin O (ASO): It is generally considered that ASO titer >500U is valuable, but some people think that adult >250U, children over 5 years old >333U, should consider its titer Increased, it is currently considered that the results of a trial are of little significance for diagnosis. If multiple trials (preferably once every 2 weeks) gradually increase the results, the diagnosis of rheumatic fever and rheumatism is of great value, such as long-term constant antibody in high units. Mostly inactive, if the high unit gradually declines, it is the disease remission period, the antibiotics or hormones used in the early stage of the disease, ASO may not increase, in addition, suffering from certain hepatitis, nephritis, nephrotic syndrome and multiple osteomyelitis ASO can also be non-specifically increased.

(2) Determination of anti-streptococcal cell wall polysaccharide antibody (ASP): According to the common antigenic property of streptococcal cell wall polysaccharide and human heart valve glycoprotein, ELISA method for determination of ASt-IgM, IgG, rheumatic valvular heart disease The rate is as high as 80% or more. On the contrary, the positive rate of non-rheumatic valvular heart disease, streptococcal infection, acute nephritis and viral myocarditis is only about 10% to 13%. This test is superior to blood sedimentation in reflecting rheumatic fever activity. The immune response after reflecting streptococcal infection is better than ASO, and has higher sensitivity and specificity.

(3) Determination of anti-streptokinase (ASK): ASK titer increased during rheumatic fever, often >800U.

(4) Determination of antihyaluronidase (AHT): When the rheumatic fever is hot, it is often >128U.

(5) Determination of anti-Streptococcus deoxyribonuclease B (ADNase B): When rheumatic fever, children often >250U, adults >160U.

(6) Anti-Streptococcus diphosphate pyridine nucleotidase (ASDA) assay: more than 1:275 U indicates rheumatic fever or rheumatic activity.

It is generally considered that two items in the above Streptococcal antibody test can be simultaneously examined, once every two weeks. If one of the two dilution tubes or two or more dilution tubes of the test has an increased antibody titer, it is rheumatic fever or rheumatism. Strong evidence.

2. A test that reflects white blood and globulin changes

(1) ESR: increased, associated with decreased albumin in blood, elevated - and 2-globulin, when rheumatic fever combined with heart failure or application of salicylic acid, hormones may not increase.

(2) C-reactive protein (CRP): positive, indicating that there is a globulin in the serum that can precipitate the C polysaccharide on the S. pneumoniae membrane. Although this test has no specificity, its level is directly proportional to the degree of rheumatic activity.

3. Experiments reflecting the destruction of connective tissue collagen fibers

(1) Serum mucin test: serum mucin > 40 mg / L (4 mg / dl) is positive.

(2) Serum diphenylamine reaction > 0.25 optical density unit.

(3) Increase in serum glycoprotein: a1>20%, a2>38%, in addition, serum protein hexose increased (normal value l210±21mg/L); aminohexose increased (normal value was 830±41mg/L).

4. Serum circulating immune complex test

(1) Complement test: serum complement C3 is increased, immunoglobulin IgA, IgG can also be increased.

(2) Peripheral blood lymphocyte procoagulant activity test: based on rheumatic fever with cellular immunity, using streptococcal cell membrane or cell wall polysaccharide antigen as specific antigen, stimulating peripheral blood lymphocytes of patients, found that its blood coagulation activity increased, positive rate More than 80% (normal people, simple streptococcal infection, viral myocarditis, coronary heart disease, positive rate is only 4% to 14%), can be used as evidence of rheumatic fever or rheumatism.

(3) Anti-myocardial antibody assay: The principle is that the streptococcal membrane has common antigenicity with mammalian myocardium, and can adsorb specific anti-myocardial antibodies in the serum of patients with rheumatic fever, and the positive rate can be as high as 70%, especially for judging whether there is any Cardiac involvement is of great significance.

5. Other

In serum rheumatoid myocarditis, serum phosphocreatine kinase (CPK) and its isoenzyme (CPK-MB) and aspartate aminotransferase (GOT) can be increased, and the degree of increase is parallel with the severity of myocarditis.

6. ECG examination

Patients with rheumatic carditis typically change to atrioventricular block (prolonged PR interval), atrial and ventricular premature contractions, and ST-T changes, atrial fibrillation and pericarditis may occur. In the past, it was considered that the PR interval was prolonged, even as high as 70% to 80%. In recent years, only about 1/3 of cases have been seen.

7. Echocardiography

Since the 1990s, the application of two-dimensional echocardiography and Doppler echocardiography for rheumatic fever and rheumatic carditis has made great progress, not only for carditis with obvious clinical symptoms, but also for heart valve ultrasound changes. High positive rate, Vasan RS also found 2 cases of acute rheumatic fever, although there is no clinical symptoms of carditis (polyarthritis and chorea), there are changes in mitral ultrasound, small nodules in the anterior mitral valve, After follow-up after treatment, this nodular change disappeared, so the author believes that these changes should be an acute cardiomyelitis manifestation of acute rheumatic fever. The most diagnostic ultrasound changes are currently considered to be:

1 valve thickening: can be diffuse valve leaf thickening or focal nodular thickening, the former can be as high as 40%, the latter can be as high as 22% to 27%, both with mitral valve more common, followed by The arterial valve, focal nodule size is about 3 ~ 5mm, located in the body and / or tip of the valve leaflet, these nodular thickening is the most characteristic morphological change, more considered rheumatoid neoplasm Forming, its morphology and activity are different from those of infective endocarditis.

2 mitral valve prolapse: the incidence of each report varies widely, can be as high as 51% to 100%, as low as 5% to 16%, this difference is considered to be related to the examiner's technical proficiency and vigilance, the valve Prolapse is more common in the anterior mitral valve (51% to 82%), and the posterior mitral valve (7%) and the aortic valve (15%) prolapse are less common.

3 valve regurgitation: is the most common valve change, mitral regurgitation is much more common than aortic valve and tricuspid regurgitation, for the skilled practitioner can accurately distinguish the physiological and pathological range of reflux, such as combined color Doppler ultrasound is more accurate. According to statistics, the incidence of mitral regurgitation is as high as 84% to 94%, and severe reflux can reach 25% in recurrent rheumatic fever.

4 pericardial effusion: mostly a small amount of effusion, occurred in 7% of initial rheumatic fever, recurrent rheumatic fever accounted for 29%, it is worth noting that although rheumatic fever, there may be multiple echocardiographic performance However, in the absence of clinical evidence of carditis, it is not easy to make a diagnosis of rheumatic fever or rheumatic carditis by some positive changes in echocardiography, so as to avoid other causes such as primary mitral valve prolapse, various Non-rheumatic valvular heart disease, cardiomyopathy, confusion of ultrasound changes caused by pericarditis.

8. X-ray chest examination

Clinically, only severe carditis can be detected at the time of physical examination when the heart is significantly enlarged. The heart enlargement of most rheumatic carditis is mild. It is difficult to find without X-ray examination. Sometimes it must be passed. The reduction of heart shadow after treatment confirmed that the heart enlargement of the original carditis had existed.

It can show prolongation of PR interval or sinus tachycardia. ST-T changes indicate that there may be myocarditis. Conventional lead (except AVR) is elevated in horseshoe down ST suggesting that there may be pericarditis.

Diagnosis and diagnosis of rheumatic fever in children

diagnosis

1. Diagnostic criteria

In response to the prevalence of foreign rheumatic fever in recent years, the American College of Cardiology revised the Jones standard in 1992. The new revised standard is mainly for the diagnosis of initial rheumatic fever.

The standard is also supplemented as follows. There are three cases, and no other causes can be found. It is not necessary to strictly enforce the diagnostic criteria, namely:

1 with chorea as the only clinical manifester.

2 concealed onset or slow-onset carditis.

3 There is a history of rheumatic fever or rheumatic heart disease. When reinfected with group A streptococci, there is a high risk of recurrent rheumatic fever.

The latest revision of the Jones standard in 1992 is one step ahead of the revised standard. It is especially suitable for patients with rheumatic fever who have developed rheumatic fever and some special conditions, but for the atypical prevalence of rheumatic fever and recurrent cases that have been popular in recent years, There is still a high rate of missed diagnosis and misdiagnosis, which can be as high as 38% to 70%.

It should be emphasized that in the application of the above criteria, a comprehensive analysis must be carried out in combination with the clinical situation, especially the specific condition of the patient, and the diagnosis of rheumatic fever can be made only after a differential diagnosis of the suspected disease.

2. The judgment scheme of "may be rheumatic fever"

The above-mentioned latest revision of the Jones standard in 1992 has not yet provided further diagnostic indicators for some atypical, mild and difficult cases of recurrent rheumatic fever that have been diagnosed in recent years. In the past, some foreign scholars suggested the development of a may rheumatism. "Hot" diagnostic criteria, but has not yet seen specific clarification, according to the author's many years of clinical work experience, using the following "may rheumatic fever" judgment program, in the reduction of missed diagnosis, received good results, the main points are as follows:

"Possible rheumatic fever" criteria: mainly for atypical, mild and recurrent cases, which have one of the following manifestations and can exclude other diseases (especially subacute infective endocarditis, systemic lupus erythematosus, rheumatoid arthritis) , tuberculosis, etc.) can make a diagnosis of "may be rheumatic fever."

(1) Rheumatic heart valve disease has one of the following conditions:

1 There is no other reason for progressive heart failure or refractory heart failure in the short term, or poor tolerance to digitalis treatment.

2 progressive palpitations, increased impotence, with fever, joint pain or nosebleeds.

3 new tachycardia, arrhythmia, first heart sounds weakened, or positive murmur changes, or new murmurs, or progressive heart enlargement, with the presence of meaningful immune indicators or acute phase reactants .

4 new palpitations, shortness of breath, accompanied by meaningful electrocardiogram, echocardiography or X-ray changes, or with meaningful immune indicators or acute phase reactants.

5 Newly developed heart symptoms, improved after anti-rheumatic treatment.

(2) After infection with upper respiratory tract staphylococcus, one of the following conditions:

1 multiple, migratory arthritis with palpitations, gas promotes aggravation.

2 multiple, migratory joint pain with fever, palpitations, shortness of breath, acute phase reactants, treated with penicillin for 2 weeks is invalid.

3 progressive onset of cardiac symptoms associated with the appearance of acute phase reactants and meaningful immune indicators; or accompanied by meaningful electrocardiogram, echocardiography or X-ray changes.

It should be emphasized that in the application of the above criteria, it is necessary to conduct a comprehensive analysis in combination with the clinical situation, especially the specific condition of the patient, and to make a diagnosis of rheumatic fever after a differential diagnosis of the suspected disease.

3. Judging the activity of rheumatic heat

The determination of rheumatic fever activity is of great significance for guiding treatment and judging prognosis. However, the judgment of rheumatic fever activity is still a difficult problem so far, especially for some special clinical types such as protracted type. This is especially the case when clinical patients are judged for activity. The traditional indicators of erythrocyte sedimentation rate and C-reactive protein are far from meeting the actual needs, because erythrocyte sedimentation rate often declines to normal after heart failure or after hormone therapy, while C reaction Proteins are transiently positive only in the early stages of the disease, suggesting that they have limited value in determining rheumatic activity. The authors suggest a comprehensive analysis of disease activity from the following aspects:

1 Review whether there is any upper respiratory tract infection in the near future.

2 Consult your medical history and detailed examination to find mild arthritis or joint pain.

3 Systematic monitoring of body temperature to detect the presence or absence of fever (especially low heat).

4 check for the presence of carditis, pay attention to whether the original heart sound, heart rate, heart rate and heart murmur properties have a positive change or new pathological murmurs, such as systolic murmur in grade II or above or new diastolic phase The noise is of great significance.

5 Pay attention to whether the heart function has a progressive decline or unexplained heart failure in a short period of time.

6 laboratory indicators such as erythrocyte sedimentation rate, C-reactive protein negative should be carried out other laboratory tests, such as glycoprotein electrophoresis (or mucin), a variety of non-specific and specific immunoassays, if conditions permit, it is best to measure anti-myocardial antibodies , ASP and PCA test, anti-myocardial antibody can be positive in acute or chronic rheumatic activity, ASP-IgM increased disease activity, PCA test has high specificity in rheumatic fever activity, cellular immune response Sexual meaning.

7 Through the above steps, if there is a big doubt in rheumatism activity, anti-rheumatic treatment can be performed for 2 weeks; if the condition is improved, it indicates the presence of rheumatism activity.

[Differential diagnosis]

It should be differentiated from other causes of arthritis, subacute bacterial endocarditis, and myocarditis.

1. Other causes of arthritis

(1) Rheumatoid arthritis: is a small symmetry of the palmar and other small arthritis, characterized by "morning stiffness" and finger spindle swelling, joint deformity later, clinically less heart damage, but echocardiography Graph examination can detect pericardial lesions and valvular lesions early, X-ray shows joint surface destruction, joint space is narrowed, osteoporosis is adjacent to bone tissue, and serum rheumatoid factor is positive.

(2) Prolonged arthritis caused by sepsis: There are often symptoms of primary infection, blood and bone marrow bacteria culture is mostly positive, and the intra-articular exudate has a purulent tendency, and pathogens can be found.

(3) Tuberculosis infection Allergic arthritis (Poncet's disease): There are exact tuberculosis infections in non-articular parts of the body, and there are often recurrent arthritis manifestations, but the general condition is good, X-ray shows no bone destruction, water Yang The symptoms of acid therapy can be alleviated but recurrent, and the symptoms subsided after anti-tuberculosis treatment.

(4) tuberculous arthritis: mostly involved in a single joint, occurs in joints that are often subject to friction or weight, such as hip, thoracic vertebrae, lumbar or knee joints, joint pain but no redness, no heart lesions, often other parts Tuberculosis lesions, X-ray shows bone destruction, nodular erythema can occur, anti-rheumatic treatment is ineffective, anti-tuberculosis treatment is effective.

(5) Leukemia, lymphoma and granuloma: It is reported that 10% of cases of leukemia have symptoms of fever and acute polyarthritis, and arthritis can be preceded by changes in peripheral blood, leading to misdiagnosis, attention should be paid to blood and bone marrow. Changes in elephants, other lymphomas and benign granulomas have similar reports.

(6) Lyme disease (Lyme disease): This disease is an epidemic caused by ticks. It usually develops symptoms 3 to 21 days after biting. The clinical manifestations are fever, chronic migratory skin erythema, recurrent Asymmetric arthritis, which occurs mostly in large joints, may have heart damage, affecting the conduction system, ECG shows different degrees of atrioventricular block, and may also have neurological symptoms such as chorea, meningoencephalitis, myelitis, Facial nerve paralysis, etc., laboratory tests for circulating immune complexes positive, ESR increased, serum specific antibody determination can be identified.

2. Subacute infective endocarditis is more common in patients with original heart valve disease, with progressive anemia, splenomegaly, ecchymosis, clubbing, and embolization symptoms in different parts of the brain, kidney or lung. Repeated blood culture positive, echocardiography can detect neoplasms on the valve.

3. Viral myocarditis often precedes or onset of respiratory or intestinal viral infections, mainly involving the affected part of the myocardium, occasionally involving the pericardium, rarely invading the endocardium, having a short fever time, may have joint pain, but no arthritis , the first heart sound in the apical area and secondary systolic murmur, arrhythmia more common, no ring erythema, subcutaneous nodules, etc., laboratory tests showed that leukopenia or normal, erythrocyte sedimentation rate, ASO, C-reactive protein are normal, complement binding The test and the neutralizing antibody are positive, and the myocardial biopsy can separate the virus.

4. Streptococcus infection status (streptococcal infection syndrome) In the case of acute streptococcal infection or 2 to 3 weeks after infection, hypothermia, fatigue, joint pain, increased erythrocyte sedimentation rate, ASO-positive, electrocardiogram may have a premature beat Dynamic or mild ST-T changes, but no heart enlargement or obvious murmur. After antibiotic treatment to control infection, the symptoms disappear quickly and no longer relapse.

5. Systemic lupus erythematosus This disease has fever, joint pain, carditis, kidney disease, etc., similar to rheumatic fever, but there are symmetrical facial butterfly erythema, white blood cell count reduction, ASO negative, anti-nuclear antibody in blood, anti-double chain DNA antibodies, sometimes positive for anti-Sm antibodies, help to rule out the disease.

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