Wind-dampness heat (rheumatic fever) is one of the common pediatric diseases that threaten the life and health of school-aged children. The condition involves non-suppurative inflammation of systemic connective tissues, primarily affecting the heart and joints. Other organs such as the brain, skin, serous membranes, and blood vessels may also be involved, but cardiac damage is the most severe and frequent. Sometimes, the heart may be affected during the first episode, and repeated attacks can lead to chronic valvular heart disease in two-thirds of affected children.

bubble_chart Epidemiology

This disease is commonly seen in school-aged children. The age distribution of 1,477 hospitalized patients with wind-dampness fever at Beijing Children's Hospital (1995–1971RH) shows that the disease predominantly affects school-aged children. Specifically, there were 17 cases under 4 years old, accounting for only 1.21%; 133 cases aged 4–6, making up 8.95%; 557 cases aged 7–10, accounting for 37.74%; and 770 cases aged 11–14, representing 52.1%. Nearly 90% of cases occur in children aged 7 and above. There is little difference in gender distribution. Most cases occur in winter and spring, coinciding with the season of upper respiratory streptococcal infections. In families with wind-dampness fever patients, the incidence is higher than in families without a history of the disease, and multiple family members may be affected. Among wind-dampness fever patients, 60–70% have the histocompatibility antigen HLA-DR₄ type, compared to only 10–15% in the control group. Crowded living conditions and poor socioeconomic status are associated with higher incidence. Therefore, the onset of wind-dampness fever is related to upper respiratory streptococcal infections, human immune responses, and environmental factors. In recent years, the incidence of wind-dampness fever has significantly declined in developed countries, and cases tend to be milder.

The etiology and pathogenesis of the disease have not yet been fully elucidated. It is generally believed that the occurrence of this disease is closely related to group A β-hemolytic streptococcal infection of the upper respiratory tract and may be a complication of streptococcal infection. The evidence includes: ① A history of hemolytic streptococcal infections such as pharyngitis, tonsillitis, or scarlet fever often occurs 1–3 weeks before the onset of the disease. ② In most patients with wind-dampness heat, group A β-hemolytic streptococci are cultured from the throat, or there is a significant increase in anti-streptococcal antibodies in the serum, such as anti-streptolysin O (ASO). ③ The incidence of wind-dampness heat increases following epidemics of streptococcal infections. ④ Treatment and prevention of hemolytic streptococcal infections with penicillin can prevent recurrence of wind-dampness heat and even reduce the likelihood of initial onset. However, administering high-dose penicillin treatment after the onset of wind-dampness heat does not affect its course, and the disease does not manifest during the streptococcal infection itself but rather 1–3 weeks afterward. Therefore, it is widely believed that the onset of wind-dampness heat is due to an immune response triggered by streptococcal infection. Streptococcal cell components and extracellular products are highly antigenic and specific. After streptococcal infection, the human body produces specific antibodies. These antibodies and antigenic substances cause degeneration and dissolution in connective tissue. Individuals who produce more antibodies following streptococcal infection have a higher likelihood of developing wind-dampness heat. Patients with wind-dampness heat exhibit higher titers of ASO or other streptococcal antibodies compared to those with uncomplicated streptococcal infections, further supporting the view that an immune response underlies the pathogenesis.

The main pathological changes occur in the collagen fibers of connective tissue, and all organs throughout the body can be affected. However, the most significant alterations are observed in the heart, blood vessels, and serous membranes. The fundamental pathological change of wind-dampness heat is the wind-dampness body, also known as the Aschoff body. The progression of the disease can be divided into the following three stages. ① The **initial stage [first stage]** is the **exudative phase**: Collagen fibers exhibit localized swelling, fibrinoid degeneration, or necrosis, accompanied by nonspecific inflammatory cell infiltration and serous exudation. This is commonly seen in the synovial membranes of joints, pericardium, and pleura. These lesions may resolve or progress to the second or **late stage [third stage]**. ② The **intermediate stage [second stage]** is the **granulomatous phase**: Granulomas are frequently found around small blood vessels in the myocardium and within the valvular membranes, forming wind-dampness bodies. The center of these bodies consists of swollen, necrotic collagen fibers, while the periphery is composed of Aschoff cells, which have abundant basophilic cytoplasm, single or multinucleated nuclei, and prominent nucleoli. ③ The **late stage [third stage]** is the **sclerotic phase (healing and scar formation phase)**: Scar tissue forms at the granuloma sites, leading to sclerosis, as seen in the valvular changes of chronic rheumatic heart disease. The wind-dampness body undergoes this **late stage [third stage]** transformation over approximately six months. Due to recurrent episodes of wind-dampness sexually transmitted disease, lesions from different stages may coexist. Additionally, wind-dampness heat may also present with nonspecific serofibrinous exudation accompanied by inflammatory cell infiltration.

**Endocardial Lesions** Endocarditis most commonly affects the valvular membranes but may also involve the papillary muscles and chordae tendineae. Among the valves, the mitral valve is most frequently damaged, followed by concurrent involvement of the mitral and aortic valves. The tricuspid and pulmonary valves are rarely affected. Early lesions include loosening and edema of the connective tissue at the valve closure margins, swelling of collagen fibers, sometimes fibrinoid degeneration, local histiocyte proliferation, and endothelial cell swelling (eyelid-like protrusions) in the valvular membrane. Subsequently, granular, wart-like vegetations appear at the valve closure margins. These vegetations are essentially white thrombi, initially formed by platelet deposition at sites of endothelial injury on the valve closure margins, followed by fibrin precipitation from the plasma. Later, fibroblast proliferation and newly formed capillaries extend from the valve base toward the lesion, leading to organization of the vegetations and resulting in valvular contracture and deformation. Similar lesions may also occur at the tips of the chordae tendineae and papillary muscles. If wind-dampness heat recurs repeatedly, the valves become thickened due to fibrous tissue hyperplasia, and the chordae tendineae shorten and thicken, leading to valvular stenosis or insufficiency.

**Myocardial Lesions** In the acute phase, interstitial connective tissue edema and perivascular fibrinoid degeneration are observed, along with inflammatory cell infiltration. The most significant lesion is the formation of wind-dampness bodies. In children, wind-dampness **Recurrent** episodes may lead to acute exudative myocarditis, which can be fulminant and rapidly result in cardiac decompensation. With repeated episodes, myocardial damage worsens, eventually leading to sclerosis and impaired circulatory function.

**Pericardial Lesions** The pericardium often develops serofibrinous inflammation. In severe cases, pericardial effusion increases and becomes turbid, though rarely hemorrhagic, with a total volume generally not exceeding 500 ml. Later, the pericardial fluid is absorbed, and fibrin undergoes organization. The two layers of the pericardium may adhere, but constrictive pericarditis is rare.

**Joint Lesions** The joint cavity exhibits serous and minor fibrinous exudation, synovial membrane congestion and edema, and mucoid degeneration, fibrinoid degeneration, and inflammatory cell infiltration in the sub-synovial connective tissue. The exudate is easily absorbed and does not cause joint deformities.

**Subcutaneous Nodules** These often occur near joints, attached to tendons and periosteum. Pathologically, they are wind-dampness bodies and are typically absorbed within weeks to months.

**Pleural and Pulmonary Lesions** During wind-dampness heat, the pleura is frequently affected, with sterile serofibrinous exudation. Excessive fibrinous exudate, once absorbed, often leads to fibrous pleural adhesions. In acute episodes, hemorrhagic pneumonia may occasionally be observed in the lungs, and Aschoff cells can also be found in the pulmonary interstitium.

Brain lesions Inflammatory infiltration and edema are observed in the cerebral membranes and parenchyma, with infiltration of lymphocytes and plasma cells, forming atypical wind-dampness bodies distributed in areas such as the striatum, substantia nigra, and cerebral cortex. Additionally, dilation and congestion of cerebral and meningeal blood vessels are seen, along with increased permeability and accompanying petechial hemorrhages.

In addition, vascular inflammation can also be observed in the spinal cord, nerve roots, and peripheral nerves. Wind-dampness granulomas can be found around blood vessels and in the small stirred pulse of the kidneys.

bubble_chart Clinical Manifestations

One to three weeks before the onset of the disease, there may be a history of short-term fever or scarlet fever due to conditions such as pharyngitis, tonsillitis, or common cold. Symptoms vary in severity and may even be absent. Throat symptoms usually disappear within about four days, after which the child feels no discomfort. One to three weeks later, the condition begins to manifest abruptly. Wind-dampness arthritis often has an acute onset, while carditis may follow a more insidious course.

General Symptoms: The child may appear listless, fatigued, with poor appetite, pale complexion, profuse sweating, and nosebleeds. Sometimes, abdominal pain may occur, which can be severe enough to be misdiagnosed as acute appendicitis. Fever is generally not very high and often irregular in pattern. A few cases may exhibit short-term high fever, but most experience prolonged low-grade fever lasting about 3–4 weeks.

Cardiac Symptoms: According to pathological statistics, almost all cases involve varying degrees of cardiac involvement. In children with wind-dampness fever, cardiac lesions are particularly prominent. The myocardium, pericardium, and endocardium may all be affected, collectively referred to as wind-dampness carditis or pancarditis, which is the most critical manifestation of pediatric wind-dampness fever. Clinical analysis of hospitalized cases at Beijing Children's Hospital showed that 73.2% exhibited clinical manifestations of carditis. Severe carditis may lead to chronic wind-dampness valvular disease. Below, we detail acute wind-dampness carditis and chronic wind-dampness valvular disease separately:

1. Acute Wind-Warmth Carditis

(1) Myocarditis: All children with wind-dampness fever exhibit varying degrees of myocardial lesions. Clinically, manifestations of myocarditis are also very common. Mild cases may show few symptoms, such as only grade I tachycardia or transient minor changes on the electrocardiogram. Severe cases present as diffuse myocarditis with pronounced clinical symptoms, often complicated by heart failure. When the myocardium is affected, the following signs may appear: ① Increased heart rate, exceeding 110–120 beats per minute, disproportionate to the degree of fever. ② Weakened heart sounds, with a dull first heart sound at the apex, sometimes accompanied by a gallop rhythm. ③ Arrhythmias may occur, including premature beats and varying degrees of atrioventricular block, with grade I being the most common. A few cases may develop complete atrioventricular block, leading to Adams-Stokes syndrome. Other forms of arrhythmia may also occasionally occur. The electrocardiogram may also show prolonged Q-T intervals and abnormal T waves. ④ The heart may be grade I or significantly enlarged.

(2) Endocarditis: The mitral valve is most commonly affected, followed by the aortic valve. A grade II to III blowing holosystolic murmur may be heard at the apex, sometimes high-pitched like a seagull's cry, radiating to the axilla and left back, unaffected by respiration or position. This murmur suggests mitral regurgitation. About half of cases may also exhibit a grade II to III diastolic mid-stage (Carey-Coombs) murmur due to rapid left ventricular filling or relative mitral stenosis. Generally, murmurs heard at the mitral area during the acute phase do not necessarily indicate irreversible organic damage to the valve. In mild carditis, murmurs are related to valve inflammation, edema, or platelet vegetations. After the acute phase, about half of these murmurs may disappear. However, if the murmur persists or does not weaken after the acute phase, the likelihood of future mitral regurgitation or stenosis is high. A diastolic murmur heard at the aortic area carries significant pathological implications and rarely disappears.

(3) Pericarditis: Severe cases in children may present with pericarditis symptoms, often coexisting with myocarditis and endocarditis. The child may exhibit precordial pain, orthopnea, and marked dyspnea. In the early stages, a pericardial friction rub can be heard at the base of the heart or the left sternal border. With significant pericardial effusion, auscultation reveals distant heart sounds. Chest X-ray fluoroscopy may show weakened or absent cardiac pulsations, with the cardiac shadow enlarged bilaterally, assuming a flask-like shape. In the supine position, the cardiac waist appears widened, while in the upright position, the shadow of the cardiac waist narrows again, aiding in differentiation from cardiac enlargement. During the acute phase, the ECG may show ST-segment elevation and low QRS voltage, followed by T-wave inversion and ST-segment depression. Echocardiography reveals an echo-free space between the left ventricular posterior wall and the pericardium.

When acute Rheumatic heart disease occurs, the myocardium, endocardium, and pericardium are often simultaneously affected. Clinically, it is difficult to distinguish which symptoms and signs are caused solely by myocarditis, endocarditis, or pericarditis, hence they are collectively referred to as wind-dampness carditis or pancarditis. Carditis occurs in 70% of cases within the first two weeks of onset, with a minority extending up to six months. In severe carditis, the heart enlarges, especially when accompanied by heart failure, often leaving chronic valvular heart disease as a sequela.

2. Chronic Valvular Heart Disease

In cases where wind-dampness fever recurs and the course is prolonged (1/2 to 2 years), inflammatory repair processes may lead to scarring and contracture on the valves or chordae tendineae, resulting in organic valvular damage. This marks the inactive chronic wind-dampness valvular heart disease stage, i.e., Rheumatic heart disease. Among these, the mitral valve is most frequently affected, accounting for about 3/4 of valvular diseases, followed by the aortic valve at 1/4 (some reports suggest up to 1/2, either alone or coexisting with mitral valve lesions). Combined mitral and aortic valve damage accounts for over 90% of wind-dampness valvular disease cases. The tricuspid and pulmonary valves are rarely affected and generally do not sustain isolated damage. Additionally, it should be noted that in children, Rheumatic heart disease with heart failure often involves active wind-dampness, which differs significantly from adult wind-dampness valvular disease. During the acute phase, a small proportion of mitral valve involvement may resolve, but 30–60% of cases ultimately result in permanent valvular damage, whereas aortic valve damage rarely resolves once it occurs.

(1) Mitral Regurgitation: Mild cases are generally asymptomatic. In more severe cases, reduced cardiac output may cause weakness, fatigue, and palpitations. Pulmonary congestion may lead to exertional dyspnea. Cardiac examination primarily reveals a grade III or higher blowing systolic murmur at the apex, characterized by spanning the entire systole or at least extending to mid-systole, radiating to the axilla, and sometimes accompanied by a systolic thrill. The first heart sound may be normal or diminished. The second heart sound may show significant splitting, and a prominent third heart sound may be audible. In mitral regurgitation, left ventricular enlargement may cause a functional mid-diastolic murmur at the apex. Chest X-ray shows left atrial and ventricular enlargement, occasionally with systolic expansion of the left atrium. Pulmonary vascular markings are normal. ECG may indicate left ventricular hypertrophy and mitral P waves. Echocardiography reveals left atrial enlargement, a markedly deepened C wave, increased EF slope, widened mitral valve opening amplitude, a tall and sharp E peak, and signs of left ventricular overload: left ventricular enlargement, widened left ventricular outflow tract, and increased motion amplitude of the left ventricular side of the interventricular septum (Table 17-2).

Table 17-2 Characteristics of Mitral Regurgitation Severity

(2) Mitral stenosis: Rheumatic endocarditis leading to mitral stenosis generally requires a disease course of at least two years or longer, with most cases requiring around 10 years. Clinical symptoms begin to appear when the mitral valve orifice area narrows to half of its normal size. Many grade I or grade II mitral stenosis patients may have obvious signs but no symptoms. Children are prone to fatigue, palpitations, and gradually develop shortness of breath, experiencing difficulty breathing during activity. Symptoms are often triggered by intense physical activity, emotional stress, respiratory infections, atrial fibrillation, etc. The cheeks and lips often appear purplish-red ("mitral facies"). Severe patients may cough, producing thin, pink frothy sputum or hemoptysis, and exhibit orthopnea, among other signs of left heart failure. With right heart failure, systemic congestion occurs, leading to hepatomegaly and tenderness, and advanced stages may present with ascites. Atrial fibrillation occurs in 30% of adult cases, and over time, mural thrombi may form, leading to systemic embolism. Physical examination primarily reveals a rumbling mid-to-late diastolic murmur at the apex, often accompanied by a diastolic thrill and an accentuated first heart sound. The pulmonary component of the second heart sound is also accentuated. An opening snap may sometimes be heard at the lower left sternal border, with low pulse pressure and a relatively fine pulse. X-ray examination shows cardiac enlargement, predominantly of the left atrium and right ventricle, along with a prominent pulmonary artery segment and pulmonary venous congestion. Electrocardiograms in grade II or higher stenosis may show right axis deviation and right ventricular hypertrophy. The P wave may be widened and sometimes elevated. Atrial fibrillation may occur in those with carditis or a prolonged disease course. Atrial fibrillation in childhood often suggests active Bi disease. Echocardiography typically reveals reduced EF slope, a square or "sail-like" anterior mitral leaflet, posterior mitral leaflet moving in the same direction as the anterior leaflet, reduced anterior mitral leaflet mobility, thickened mitral valve echoes, and left atrial enlargement. In cases of mitral stenosis combined with mitral regurgitation, if the stenosis is more prominent, the anterior mitral leaflet shows rapid early diastolic descent, with a visible E peak followed by a slow descent plateau, forming a "riding-like" pattern.

The characteristics of the severity of mitral stenosis are shown in Table 17-3.

Table 17-3 Characteristics of the Severity of Mitral Stenosis

(3) Aortic valve insufficiency: The aortic valve damage caused by rheumatic endocarditis manifests as insufficiency. The compensatory period of the heart is relatively long in aortic valve insufficiency. When the left ventricle compensates without pulmonary congestion, there may be no symptoms. Therefore, Grade I or Grade II patients show no obvious symptoms. More severe patients experience palpitations, prominent carotid artery pulsations (pulsations are noticeable throughout the body), and some children cannot lie on their left side due to discomfort in the left chest caused by strong pulsations, sweating, etc. When the left ventricle decompensates, symptoms of left heart failure appear. Some patients with seasonal diseases experience angina pectoris, often occurring during deep sleep at night. The onset is marked by pale skin, palpitations, elevated blood pressure, and rapid breathing, followed by flushed skin and sweating. Angina pectoris can often lead to sudden death. When left-sided heart failure occurs, symptoms of pulmonary congestion, pulmonary edema, and orthopnea may appear, eventually leading to right-sided heart failure. Physical examination: Generally, a high-pitched, blowing diastolic early-to-midstage murmur can be heard in the second auscultation area of the aortic valve, i.e., the left 3rd and 4th intercostal spaces near the sternum. Sometimes, it can also be heard at the right 2nd intercostal space. It is most easily heard with a diaphragm-type chest piece of the stethoscope and becomes clearer during inspiration and when sitting forward. The second heart sound of the aortic valve is weakened or absent. When aortic pressure increases, it often intensifies. Severe patients often have a third heart sound. Additionally, an ejection systolic murmur is often heard at the aortic valve area, and a diastolic advanced-stage murmur (Austin-Flint murmur) can also be heard at the apex, resembling mitral stenosis. This murmur may be presystolic, diastolic mid-stage, or both, caused by functional mitral stenosis. Chest percussion reveals the heart enlarged to the left and downward, with enhanced and heaving apical impulses. Other clinical features include peripheral vascular signs due to aortic valve insufficiency, such as increased pulse pressure, water-hammer pulse, capillary pulsation, pistol-shot sounds (Duroziez murmur, a systolic and diastolic murmur heard over the femoral or other peripheral large arteries), de Musset sign (rhythmic head nodding due to strong carotid artery pulsations), and Hill’s sign (when aortic regurgitation is present, the systolic pressure difference between the femoral and brachial arteries can sometimes reach 60–100 mmHg). X-ray examination shows left ventricular enlargement, with significant enlargement in Grade II or higher cases, forming a boot-shaped heart as the left ventricle extends downward. Fluoroscopy reveals enhanced aortic and left ventricular pulsations. The electrocardiogram may be normal or show left ventricular hypertrophy. If mitral insufficiency is present, left atrial enlargement, right ventricular enlargement, and pulmonary congestion may occur. Echocardiography shows that the aortic valve does not close into a single line during diastole but forms two echoes with a distance of >1 mm between them. Sometimes, fine tremors can be seen on the closure line. The opening and closing rates of the aortic valve accelerate, and the anterior mitral leaflet shows diastolic fine tremors.

Mitral insufficiency often coexists with mitral stenosis, whereas isolated mitral insufficiency is common, while isolated mitral stenosis is rare. Aortic valve insufficiency often exists alone and is usually congenital. Children with aortic insufficiency are prone to infective endocarditis.

Arthritis: Characterized by migratory and polyarticular involvement, primarily affecting large joints such as the knees, ankles, wrists, and elbows. Small joints may occasionally be affected simultaneously. Local redness, swelling, heat, and pain appear and usually resolve within days or weeks without leaving deformities. Mild cases may only present with arthralgia, often accompanied by fever and elevated ESR. In recent years, severe joint redness, swelling, and pain have become extremely rare. Patients with typical arthritis often do not develop cardiac involvement, whereas those with arthralgia often develop carditis. Therefore, arthralgia holds significant diagnostic importance.

Chorea is characterized by varying degrees of irregular involuntary movements dominated by the circuit of element qi. Typical symptoms include involuntary movements of the entire body or partial muscles, most commonly in the limbs, leading to an inability to hold objects, fasten buttons, or even eat due to excessive movements of the mouth and tongue, severely affecting daily life. Facial muscle spasms may cause peculiar expressions and speech impairments, along with frowning, forehead raising, eye closure, shoulder shrugging, and neck retraction. These movements are mostly bilateral or limited to one side, worsening with excitement or concentration and disappearing during sleep. Muscle strength and sensation are usually unaffected. The condition predominantly occurs after the age of 6, peaking between 8–12 years, and significantly decreases after adolescence. It is more common in girls than boys. Chorea typically appears 2–6 months after streptococcal infection, with a usual course of 1–3 months, though it may recur or occasionally persist for over a year. Chorea is one of the main manifestations of wind-dampness heat and may occur alone without carditis or chronic wind-dampness valvular membrane disease, or coexist with other wind-dampness heat symptoms, though it is also seen in children with arthritis. Approximately 25% of children with chorea may eventually develop carditis. When chorea occurs alone, there is generally no fever, with normal or slightly elevated ESR, and most anti-streptolysin O levels remain within the normal range. Other auxiliary tests may also show no significant abnormalities.

skin disease changes

1. Subcutaneous nodules are a symptom of wind-dampness heat, generally manifesting as round nodules the size of peas. They may protrude from the skin, are not adherent to it, and can move freely, usually without tenderness. Some larger ones may reach 1–2 cm in diameter, varying in number from a few to dozens. They commonly appear on the extensor tendon sheath attachments of joints such as the elbows, wrists, knees, and ankles, as well as on the scalp or alongside the spine. Sometimes they are symmetrically distributed. The nodules may persist for days to months, appearing and disappearing intermittently, and typically vanish naturally within 2–4 weeks. Subcutaneous nodules often coexist with carditis, usually appearing weeks after the onset of illness, serving as a prominent marker of wind-dampness activity. In recent years, they have become less common, with an incidence rate of about 1–4%. Subcutaneous nodules are not unique to wind-dampness heat and may also be seen in rheumatoid arthritis.

2. Erythema annulare (ring-shaped rash) — Skin exudative sexually transmitted disease changes can cause urticaria, purpura, maculopapular rash, erythema multiforme, erythema nodosum, and erythema annulare, among which erythema annulare holds the greatest diagnostic significance and is characteristic of wind-dampness heat. The incidence of erythema annulare is approximately 10%. It usually appears during a recurrence of wind-dampness heat and is often accompanied by carditis. It is most commonly seen on the trunk and flexor surfaces of the limbs, presenting as ring-shaped or semicircular with slightly raised edges and a pale pink color, without pain or itching. The skin inside the ring remains normal in color. This type of rash often becomes more noticeable after friction and may fade in and out within a day, leaving no desquamation or pigmentation. Erythema annulare may appear intermittently and sometimes does not correlate with wind-dampness activity.

Pneumonia and pleuritis — These are relatively rare. Most cases involve nonspecific exudative changes, often accompanied by severe carditis.

bubble_chart Auxiliary Examination

The child's blood routine examination may show grade I anemia, leukocytosis, and a shift to the left. The erythrocyte sedimentation rate (ESR) is accelerated, but the acceleration is not significant in cases of heart failure. The C-reactive protein (CRP) is positive and appears earlier than the accelerated ESR, but it also disappears more slowly and is generally unaffected by heart failure.

Evidence of streptococcal infection:

(1) Throat swab culture may sometimes yield group A β-hemolytic streptococci, but in some Bi disease patients, especially after antibiotic treatment, the throat culture may be negative.

(2) Immunological studies: In wind-dampness fever, one of the following tests is often positive: ① The serum anti-streptolysin O (ASO) titer is increased, with a positive result at 1:400 or higher. ASO appears in the serum about 2 weeks after streptococcal infection, gradually rises, peaks at 4–6 weeks, and returns to normal by 8–10 weeks. In wind-dampness fever patients, 75–80% are ASO-positive. In 20% of patients, ASO does not rise, which may include some cases of occult carditis and chorea. ASO declines slowly and may remain elevated for 5–6 months after ESR normalizes. Anti-wind-dampness treatment can reduce ASO levels. Non-specific ASO elevation may occur if the serum sample is contaminated by bacteria, hemolyzed, or in cases of hyperlipoproteinemia, hepatitis, or nephrotic syndrome, which should be ruled out. A单纯 ASO elevation only indicates recent streptococcal infection. ② The serum anti-streptokinase titer is increased, with a positive result at 1:40 or higher. ③ The serum anti-hyaluronidase titer is increased, with a positive result at 1:2048 or higher. About 95% of cases show positivity in all three tests. Additionally, there are anti-deoxyribonuclease B (anti-DNAase B) and anti-nicotinamide-adenine dinucleotidase (anti-NADase). These antibodies rise 1 week after streptococcal infection and may persist for several months. Serial testing showing rising or falling antibody titers has diagnostic value. Anti-DNAase B remains positive the longest and is diagnostically valuable for chorea and occult carditis patients. Chorea usually occurs 2–6 months after streptococcal infection, so antibody titers are mostly normal.

Serum protein electrophoresis shows decreased albumin and increased α- and γ-globulins. Mucoproteins may also increase, exceeding 4.2 mg% (normal range: 1.7–4.2 mg%). Immunoglobulin testing shows elevated IgA in the acute phase. Anti-myocardial antibody testing is positive in 55% of wind-dampness carditis patients, and 20–30% of wind-dampness chronic valvular disease patients without active wind-dampness fever may also test positive. Post-streptococcal infection states can also yield positive results.

In cases of myocarditis, serum aspartate aminotransferase (AST), creatine phosphokinase (CPK), and lactate dehydrogenase (LDH) may be elevated.

bubble_chart Diagnosis

The diagnosis of rheumatic fever primarily relies on a comprehensive assessment of clinical manifestations. Due to the lack of specific diagnostic methods, the modified Jones criteria for rheumatic fever remain the current standard. Major manifestations include carditis, polyarthritis, chorea, subcutaneous nodules, and erythema marginatum. The diagnosis of carditis should meet at least one of the following four criteria: ① a new significant murmur, such as a pansystolic murmur at the apex or a mid-diastolic murmur; ② cardiac enlargement; ③ pericarditis; or ④ congestive heart failure. Minor manifestations include fever, elevated C-reactive protein or leukocytosis, a history of rheumatic fever, or rheumatic valvular heart disease.

Clearly, major manifestations hold greater diagnostic significance than minor ones, and the presence of two major manifestations plus two minor manifestations is considered reliable. Notably, the combination of polyarthritis, fever, and elevated erythrocyte sedimentation rate is commonly seen in juvenile Bi disease, systemic lupus erythematosus, suppurative arthritis, and subcutaneous nodule virus. Additionally, for early or atypical mild cases of rheumatic fever, a thorough understanding of the medical history, careful observation of disease progression, and assessment of treatment response are essential for a definitive diagnosis. Laboratory tests primarily focus on evidence of recent streptococcal infection and systemic inflammation; the absence of either makes diagnosis difficult. Overdiagnosis not only leads to unnecessary treatments but also subjects patients to long-term prophylactic medication, imposing significant financial and psychological burdens. Conversely, underdiagnosis may result in missed cases of atypical carditis, potentially progressing to chronic valvular heart disease and lifelong disability.

Furthermore, determining whether rheumatic fever is active is a critical aspect of diagnosis. The following three scenarios suggest ongoing rheumatic activity: ① persistent abnormal body temperature, failure to gain weight, or lack of recovery in exercise tolerance; ② unstable heart rhythm, frequent changes, or rapid pulse; and ③ elevated erythrocyte sedimentation rate, persistently positive C-reactive protein, no decline in anti-streptococcal antibody titers, or failure of white blood cell counts to normalize.

bubble_chart Treatment Measures

In the treatment of wind-dampness heat, the following principles should be observed: ① Early diagnosis and rational treatment to prevent irreversible changes in the heart due to disease progression; ② Based on the severity of the condition, select appropriate anti-wind-dampness medications to prevent death in critically ill children, promptly control symptoms in general cases, and reduce the suffering of the child; ③ Control and prevent group A β-hemolytic streptococcal infections to prevent disease recurrence; ④ Wind-dampness heat is a chronic disease prone to recurrence. During repeated and long-term medication, attention should be paid to the occurrence of side effects, so the benefits and risks should be weighed for rational use.

Treatment of acute wind-dampness heat

1. Bed rest and activity control based on the condition

During the acute phase, such as fever and joint swelling and pain, bed rest should be maintained until acute symptoms disappear. For those with carditis complicated by heart failure, absolute bed rest is required. Generally, those without obvious cardiac involvement should rest for about 1 month; those with cardiac involvement require about 2–3 months; those with cardiomegaly and heart failure need about 6 months before gradually resuming normal activities.

2. Diet: Provide easily digestible foods rich in protein, carbohydrates, and vitamin C, preferably in small, frequent meals. For those with congestive heart failure, salt and fluid intake should be appropriately restricted. Children on corticosteroids should also have their salt intake moderately limited.

3. Control of streptococcal infection: Administer intramuscular penicillin at 400,000 units twice daily for 10–14 days, or a single intramuscular injection of benzathine penicillin G at 1.2 million units. If penicillin cannot be used, erythromycin at 30 mg/kg/day divided into 3–4 oral doses for 10 days may be substituted.

4. Use of anti-wind-dampness drugs: Commonly used medications include aspirin and adrenal corticosteroids. Both have antipyretic, joint symptom-relieving, and anti-inflammatory effects that suppress carditis. The choice, dosage, and duration of treatment must be determined based on clinical manifestations. Adrenal corticosteroids are more potent, and prednisone must be the first choice for carditis with heart failure, as it can save the lives of critically ill patients. Aspirin is the first choice for polyarthritis, while neither has significant effects on chorea. Most initial episodes of wind-dampness heat resolve spontaneously within 9–12 weeks. Anti-wind-dampness drugs only suppress inflammatory reactions, so the treatment course should last 9–12 weeks or longer, depending on the severity of the condition.

(1) Aspirin: Dosage is 80–100 mg/kg/day, not exceeding 3–4 g daily. A few patients may require an increase to 120 mg/kg/day, administered every 6 hours in 4 divided oral doses. If the effect is insufficient or toxic reactions occur, serum aspirin levels should be measured, and the dose adjusted to maintain levels between 20–25 mg/dl to avoid toxicity. The initial dose should be continued until body temperature normalizes, joint symptoms disappear, and ESR, C-reactive protein, and white blood cell counts return to normal, usually about 2 weeks. Then reduce to 3/4 of the original dose for another 2 weeks, followed by gradual tapering until complete discontinuation. For simple arthritis, treatment lasts 4–6 weeks; for grade I carditis, 12 weeks is recommended. Aspirin inhibits prothrombin synthesis and affects platelet adhesion, which may lead to bleeding tendencies, epistaxis, and gastrointestinal bleeding. If tinnitus or hearing impairment occurs, reduce the dose; if acidosis or psychiatric symptoms occur, discontinue use. Taking aspirin after meals can reduce gastrointestinal symptoms like nausea and vomiting. If still intolerable, switch to enteric-coated tablets. Combining aspirin with antacids reduces efficacy. Recent reports indicate that aspirin may cause hepatocyte damage, elevated transaminases, and other manifestations of toxic hepatitis.

(2) Prednisone: The dosage is 2mg/kg/d, divided into 3-4 oral doses. For severe carditis, the dose can be increased to 100mg/d. The initial dosage should be maintained for 2-3 weeks, followed by a gradual reduction until complete discontinuation at 12 weeks. Alternatively, aspirin therapy can be added one week before stopping prednisone and continued for 6-12 weeks, with the duration adjusted based on the condition. Adverse reactions to prednisone may include obesity, moon face, hirsutism, acne, etc., which gradually disappear after discontinuation. Other potential side effects include hypertension, glycosuria, psychiatric abnormalities, convulsions, peptic ulcers, osteoporosis, spread of infection, and developmental delays. To prevent adrenal insufficiency, prednisone must be tapered off slowly, typically over 3-4 weeks.

After treatment with adrenocortical hormones and aspirin, rebound phenomena often occur when the medication is discontinued or the dosage is reduced, with the former being more common. The cause of the rebound remains unclear, but it may be due to the premature discontinuation of medication before the inflammatory process of wind-dampness has fully resolved, allowing the natural course of wind-dampness-heat to re-emerge. Rebound phenomena typically occur within 2 weeks of dosage reduction or discontinuation. Mild cases may present with fever, arthralgia, the reappearance of heart murmurs, increased erythrocyte sedimentation rate, and positive C-reactive protein. Severe cases may develop pericarditis, cardiomegaly, and heart failure. Mild cases usually resolve on their own within a few days and rarely require medication, while severe cases necessitate the reintroduction of aspirin therapy.

5. Treatment of Chorea Mainly involves symptomatic and supportive therapy. The living environment should be quiet, with enhanced nursing care to prevent injuries and avoid environmental stimuli. Mild cases can be managed with sedatives such as phenobarbital or diazepam. Salicylic acid and adrenocortical hormones show limited efficacy. Recent reports suggest that haloperidol 1mg combined with an equal dose of Artane, administered twice daily, can quickly control chorea movements and reduce the side effects of haloperidol, yielding better results.

6. Treatment of Heart Failure Severe carditis and cardiomegaly increase the risk of heart failure. In addition to adrenocortical hormone therapy, digoxin or intravenous cedilanid and fast-acting diuretics such as furosemide should be administered (see the section on heart blood vessel diseases for details on heart failure).

Treatment of Chronic Valvular Disease Unless clinically active manifestations requiring anti-rheumatic drugs are present, the treatment for those without clinical signs of wind-dampness activity primarily focuses on the following aspects.

1. Activity Control Due to organic valvular lesions causing cardiac hypertrophy, enlargement, and generally reduced cardiac compensatory function, activity levels should be carefully controlled in these children, avoiding strenuous exercise.

2. Long-Term Digitalis Therapy For chronic congestive heart failure, long-term oral digitalis is recommended, with doses adjusted as needed to maintain an effective maintenance level.

3. Tonsillectomy If chronic tonsillitis is present, tonsillectomy may be performed after wind-dampness-heat is controlled. However, penicillin should be administered 2–3 days before and 1–2 weeks after surgery to prevent infective endocarditis. The same precaution applies before and after tooth extraction.

4. Surgical Considerations In cases of severe valvular damage, valvuloplasty or valve replacement may be performed to restore normal valve function, significantly improving clinical symptoms in critically ill children. However, due to the ongoing growth and development in children, issues such as relative stenosis of the replacement valve, durability of the prosthetic valve, postoperative anticoagulation therapy, and infection prevention must be carefully considered. Strict adherence to indications is essential. Generally, the indications are as follows:

(1) Indications for Mitral Valve Replacement: ① Cardiac function class III to IV; ② Two or more episodes of thromboembolism; ③ Left atrial enlargement with atrial fibrillation or atrial wall calcification; ④ Progressive pulmonary hypertension with worsening condition.

(2) Indications for Aortic Valve Replacement: ① Aortic valve lesions causing significant coronary insufficiency, syncope, or heart failure; ② If objective test results are positive and the child exhibits myocardial ischemia symptoms, surgery should be performed even if cardiac function is relatively preserved (less than class III).

bubble_chart Prognosis

The prognosis of wind-dampness heat primarily depends on whether it progresses to rheumatic heart disease. The severity of the initial carditis and the occurrence of recurrences are the main factors determining the prognosis of rheumatic heart disease. Recurrences of wind-dampness heat often mimic the initial presentation—if carditis was present initially, it will likely recur in subsequent episodes. Patients with significant cardiac involvement at the onset, those with multiple recurrences, and those complicated by heart failure have a poor prognosis and often develop chronic wind-dampness valvular heart disease. Among children with acute wind-dampness heat, 60% develop valvular lesions (compared to 10–20% in adults), and this rate can rise to 90% in those with two or more recurrences. A 10-year follow-up study (1950–1960) of 497 pediatric cases of wind-dampness heat abroad yielded the following results: - No carditis at treatment: 6% developed valvular disease after 10 years. - Grade I systolic murmur at the apex: 30%. - Grade II–III systolic murmur at the apex: 26%. - Biphasic murmurs at the apex: 37%. - Murmurs at the base: 45%. - Heart failure: 68%. - Pre-existing cardiac lesions: 67%. Chorea has a favorable prognosis, often resolving spontaneously within 4–10 weeks with rare recurrences, though a few patients may retain neuropsychiatric symptoms. With anti-wind-dampness treatment and prophylaxis, the recurrence rate of wind-dampness heat can be reduced to 10%; otherwise, half of the patients may experience recurrences, with some later developing valvular damage. Polyarthritis can achieve complete recovery.

The recurrence rate of wind-dampness heat is 30–75%. Patients with a history of wind-dampness heat are more prone to recurrences upon Group A streptococcal infection. Among those with a history of rheumatic carditis, about 30% relapse after a new Group A streptococcal infection, compared to 10% in those with prior wind-dampness heat but no carditis. Each recurrence worsens valvular damage. Patients with higher antibody responses after streptococcal infection have higher recurrence rates; at the same antibody level, those with prior carditis relapse more frequently than those without murmurs. In patients with wind-dampness valvular disease, symptoms of heart failure often recur abruptly, accompanied by new murmurs, ECG changes, fever, arthralgia, skin manifestations, chorea, or abdominal pain—these should raise suspicion of a wind-dampness heat recurrence.

bubble_chart Prevention

The prevention of wind-dampness heat can be divided into two types: prevention of initial onset and prevention of recurrence. After the initial infection with group A hemolytic streptococcus, the incidence of wind-dampness heat is about 1%, and early detection of streptococcus is difficult, so preventing the initial onset of Saposhnikovia Root dampness-heat is not easy to achieve. Only patients diagnosed with streptococcal infection should receive early penicillin treatment. Patients with wind-dampness heat are prone to recurrence after streptococcal infection, with a recurrence rate of approximately 75% within the first 3 years after the first episode of wind-dampness heat. Each recurrence worsens heart damage, so preventing streptococcal infection is crucial for preventing the recurrence of Saposhnikovia Root dampness-heat. The preventive methods are as follows.

1. Prevention of initial onset Upper respiratory tract infections caused by group A β-hemolytic streptococcus, such as scarlet fever, tonsillitis, and pharyngitis, are triggers for wind-dampness heat. Therefore, preventing the initial onset of wind-dampness heat must be taken seriously, and appropriate treatment should be given. For the diagnosis of streptococcal infection, refer to the chapter on cell pestilence diseases in the nineteenth section. Since clinical manifestations caused by group A viruses can also be caused by other bacteria, it is necessary to perform a throat culture before any treatment is administered. At this stage, almost all cultures will yield positive results for group A streptococcus. If the first throat culture is negative but clinical suspicion of streptococcal infection remains, a second throat culture should be performed.

To achieve the goal of preventing the initial onset of wind-dampness heat, treatment for streptococcal infection should begin immediately after confirmation: ① Intramuscular injection of benzathine penicillin G: For those weighing <25 kg, 600,000 units can be administered once; for those weighing >25 kg, 1.2 million units can be administered once. ② Alternatively, intramuscular injection of penicillin 400,000 units twice daily for 10 days. ③ For those allergic to penicillin, erythromycin 30 mg/kg/day (not exceeding 1 g per day) can be used for 10 days. Sulfonamides are only effective for preventing recurrence and should not be used to treat streptococcal infections.

2. Prevention of recurrence For patients with wind-dampness heat, if an upper respiratory streptococcal infection occurs, the risk of wind-dampness heat recurrence is very high. Recurrence can occur regardless of the presence of obvious symptoms, and even with aggressive treatment of symptomatic infections, prevention may still fail. Therefore, the success of preventing Saposhnikovia Root dampness-heat recurrence depends on sustained preventive measures rather than solely on treatment during acute episodes of streptococcal pharyngitis. Thus, patients with a history of wind-dampness heat, chorea, or wind-dampness carditis should receive long-term continuous preventive measures.

Preventive measures are as follows: ① Intramuscular injection of benzathine penicillin G 1.2 million units every 4 weeks. ② Oral penicillin V 250,000 units twice daily, but adherence to oral medication is challenging and requires good cooperation from the patient. This method can be used for patients with a low recurrence rate. ③ For those allergic to penicillin, oral sulfadiazine or erythromycin can be used. Sulfadiazine 1.0 g once daily (or 0.5 g once daily for those weighing <25 kg). Erythromycin 0.25 g twice daily.

Intramuscular injection of benzathine penicillin G is more effective. According to follow-up observations by the pediatric department of Shanghai First Medical College, the recurrence rate is six times higher without it. Penicillin is more effective than sulfonamides for prevention and should be continued into adulthood. During the use of penicillin or other anti-streptococcal drugs to prevent Saposhnikovia Root dampness-heat recurrence, streptococcal infections may still occur, clinically presenting only as fever and sore throat, with mostly negative throat swab cultures. In such cases, penicillin or other anti-streptococcal drugs should be promptly added to the treatment.

bubble_chart Differentiation

In terms of fever, attention should be paid to differentiating it from subcutaneous node disease or other chronic infections. In children with wind-dampness valvular heart disease, irregular fever should be carefully distinguished as either a recurrence of wind-dampness heat or a complication of infective endocarditis.

Post-streptococcal infection state (post-streptococcal infection syndrome) is easily confused with atypical wind-dampness fever. The former manifests as low-grade fever, arthralgia, elevated ASO titers, and moderate increase in ESR after tonsillitis or upper respiratory infection. Electrocardiogram may show transient premature beats or grade I ST-segment and T-wave changes, but no significant murmurs. It resolves quickly after penicillin treatment or low-dose prednisone and does not recur, unlike wind-dampness fever.

Regarding the heart, functional heart murmurs should first be excluded. Such murmurs are common in school-age children, located at the left sternal border (3rd–4th intercostal space) or near the apex, usually grade II (occasionally grade III). They are characterized by a soft, sometimes musical quality, limited to early-mid systole, with limited transmission. Congenital heart defects (e.g., congenital mitral regurgitation, partial atrioventricular canal) should also be differentiated. These are usually detected in infancy, making differentiation less challenging. Viral pericarditis and myocarditis have become more prevalent recently, complicating the diagnosis of atypical wind-dampness carditis. Viral cases often follow a clear respiratory infection, with rapid cardiac abnormalities but no significant murmurs, and arrhythmias are more common. Wind-dampness pericarditis must also be distinguished from subcutaneous node pericarditis. Additionally, left atrial myxoma can mimic wind-dampness fever and rheumatic heart disease, but echocardiography reveals abnormal echoes in the left atrium. Mitral regurgitation due to papillary muscle or chordae tendineae rupture, papillary muscle dysfunction, or mitral valve prolapse can be differentiated by echocardiography.

For joints, differentiation is needed from rheumatoid arthritis, systemic lupus erythematosus, subcutaneous node Bi disease (Poncet disease), leukemia, hemarthrosis, brucellosis, serum sickness, post-infectious arthritis, and suppurative arthritis.

Distinguishing from juvenile Bi disease can be challenging. The following features are more typical of Bi disease: ① Irregular high fever, often remittent, with clinical condition better than expected for the fever; ② Predominantly affects small joints, rarely migratory, leading to deformities over time (e.g., fusiform finger swelling); ③ Rarely involves the heart, with valvular disease being exceptionally rare.

Subcutaneous node Bi disease has these characteristics: ① Subcutaneous node lesions, often primary complex or bronchial lymph node subcutaneous node; ② Positive subcutaneous node bacillus test; ③ Skin changes, notably erythema nodosum; ④ May accompany herpetic keratoconjunctivitis.

Differentiation from other connective tissue diseases (e.g., systemic lupus erythematosus, dermatomyositis) is discussed elsewhere.

Arthralgia should be distinguished from growing pains and joint hypermobility syndrome. Growing pains involve unexplained lower limb pain in 3–5-year-olds, typically around the knees or thigh/ankles, occurring at night and lasting minutes to hours, relieved by massage and resolving over years.

Joint hypermobility syndrome has an unclear etiology, possibly genetic. Pain, often in the knees or lower limbs, worsens with activity. Features include joint laxity: hyperextensible elbows/knees, excessive finger flexion/extension, and palms touching the floor when bending forward. Habitual shoulder dislocation in childhood is common. Symptoms usually improve with age.

Differential Diagnosis of Chorea It should be differentiated from habitual spasms, which involve the repetition of a single action and can disappear when the child's attention is diverted. Athetosis involves slower movements, usually limited to the limbs. Familial chorea presents with a progressively worsening course, making it easier to distinguish.

Differential Diagnosis of Subcutaneous Nodules In childhood, benign non-wind-dampness subcutaneous nodules may occasionally be observed on the scalp, elbows, anterior tibial areas, hands, and feet. Their pathological changes include central fibrinoid necrosis and infiltration of surrounding histiocytes and mononuclear cells. These nodules resolve spontaneously but may recur, typically ceasing to appear after several months or even years. Apart from the nodules, patients exhibit no symptoms of connective tissue diseases, and their serum tests for antinuclear antibodies and rheumatoid factors are negative. No treatment is required.