Dr. Mohammed Waheeb. Lec. 2. Rheumatic fever. Wed 25 / 2 / مكتب اشور للاستنساخ

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1 Dr. Mohammed Waheeb Lec. 2 Rheumatic fever Wed 25 / 2 / مكتب اشور للاستنساخ

2 Rheumatic Fever Definition: it is an immune complex disease affecting mainly connective tissue of heart, joint, brain and the skin. Epidemiology Rare in developed world. Still common in developing countries. Peak incidence ~5-15yr. ARF (acute rheumatic fever) is a major problem in the high-risk areas of the tropics, in countries with limited resources, and in communities with minority indigenous populations. In those less developed nations, post ARF heart disease is the most commonly acquired heart disease in hospitalized children, adolescents, and young adults. In some areas, the incidence of this entity exceeds that of congenital heart disease. Rheumatic fever causes a chronic progressive damage to the heart and its valves. Until 1960, it was a leading cause of death in children and a common cause of structural heart disease. The disease has been known for many centuries. Baillou ( ) first distinguished acute arthritis from gout. Sydenham ( ) described chorea. In 1812, Charles Wells associated rheumatism with carditis and provided the first description of the subcutaneous nodules. 1

3 The connection with scarlet fever was made in the early 1900s. In 1944, the Jones criteria were formulated to assist disease identification. These criteria, with some modification, remain in use today. The introduction of antibiotics in the late 1940s allowed for the development of treatment and preventive strategies. Sex No sex predilection exists, except that Sydenham chorea occurs more often in females than in males. Age Although individuals of any age group may be affected, most cases are reported in persons aged 5-15 years. Patterns of presentation of ARF The first pattern is a sudden onset, begins as polyarthritis 2-6 weeks after streptococcal pharyngitis, and is usually characterized by fever and toxicity. If the initial abnormality is mild carditis, ARF may be insidious or subclinical. Causes This auto immune disease follow throat infection with group A-Beta hemolytic streptococci (Rheumatogenic strain) by about 2-3weeks ARF has been linked definitively with a preceding streptococcal infection, usually of the upper respiratory tract. 2

4 Predisposing factors over crowding poor housing bad ventilation low socioeconomic standard Pathogenesis 2 mechanisms: First: Releasing toxins that causes damage to connective tissue ---> release auto antigens in to circulation ---> stimulation of body to form and release auto antibodies against this connective tissue ---> causing rheumatic lesion Second Cross reaction these strains possess an antigen immunologically similar to that in heart connective tissue so produced antibodies against streptococci can react with the heart. 3

5 Pathophysiology ARF is a sequela of a previous group A streptococcal infection, usually of the upper respiratory tract. One beta-streptococcal serotype (e.g. M types 3, 5, 18, 19, 24) is linked directly to ARF. Evidence is very strong that the M protein in certain streptococci subtypes is responsible for antigenicity. Non group A streptococci has never been shown to cause this disease. The disease involves the heart, joints, central nervous system (CNS), skin, and subcutaneous tissues. It is characterized by an exudative and proliferative inflammatory lesion of the connective tissue, especially that of the heart, joints, blood vessels, and subcutaneous tissue. Pathology A fibrinoid degeneration affecting connective tissue with an inflammatory oedema. Aschoff s nodules: paravascular nodules, consist of a center of fibrinoid degeneration surrounded with Aschoff's giant cells, lymphocytes and fibroblasts. 4

6 Clinical picture A patient has a history of recent streptococcal infection 2-3 weeks ago as (tonsillitis- pharyngitis -scarlet fever). Rheumatic manifestations are divided into major and minor criteria: Major criteria Carditis Arthritis Chorea Subcutaneous nodules Erythema marginatum Minor criteria o Clinical: Fever, arthralgia. o Laboratry: Acute phase reactants (leukocytosis, increased ESR, C- reactive protein), prolonged PR interval. 5

7 Rheumatic carditis (pan carditis) Involves all layers of the heart: Endocarditis: affects valves mainly: mitral valvitis (70%) Stenosis: early due to inflammatory oedema. Leading to a mid-diastolic rumbling murmur over apex and localized with accentuated S1. Incompetence: due to destruction and deformity of the valve. Leading to a pansystolic blowing murmur over apex and propagated to axilla with muffled S1. Aortic valvitis Myocarditis: Incompetance: due to destruction and deformity of the valve. Leading to an early diastolic soft murmur over aortic area and propagated to apex. Tachychardia, not proportional to the fever and continuous with sleep. Myocardial dilatation, poor quality heart sounds. Prolonged PR interval. Heart failure. Arrhythmia. 6

8 Pericarditis: Dry Pain: stitch-like and localized. Pericardial rub: superficial, scratchy, heard near to sternum and not related to respiration. Effusion Increase cardiac dullness. Distant heart sounds. Rheumatic arthritis Affecting big joints (knee-ankle-elbow) 2 or more joints. Migratory with signs of inflammation (red, hot, swollen, and limitation of movement). Fleeting arthritis migrate from one to the other joint. Dramatic response to salicylates. Rheumatic chorea (sydenham's chorea) Common in females (8-12y). It is due to involvement of basal ganglia in rheumatic process. Its manifestations appear late. 7

9 3 MAIN MANIFESTATIONS: 1. Involuntary movement. 2. Hypotonia. 3. Emotional instability. 1) Involuntary movement: o Affecting face, limb, and tongue. o Movement is involuntary, sudden, and jerky. o Patient complains from falling of objects from the hands. o Tongue movement interferes with speech. 2) Hypotonia: o Mainly proximal than distal. o Associated with hyperreflexia. o If sever it leads to paralysis (chorea mollis). 3) Emotional instability: o Sudden crying. o Sudden laughing 8

10 Subcutaneous nodules They are painless subcutaneous firm nodules freely mobile under the skin. Site: over extensor surfaces and bony prominences. Indicate sever carditis. Erythema marginatum They are rings of erythema with clear center, not painful, not itchy. Site: over trunk and proximal parts of the extremities. Diagnosis of ARF requires a high index of suspicion. Guidelines of diagnosis used by the American Heart Association include major and minor criteria (i.e. modified Jones criteria). In addition to evidence of a previous streptococcal infection, the diagnosis requires 2 major Jones criteria or 1 major plus 2 minor Jones criteria. Diagnosis (history-examination-investigation) HISTORY Recurrent tonsillitis, pharyngitis, or scarlet fever. Abnormal movements. 9

11 EXAMINATION According to modified jones criteria: 2 MAJOR CRITERIA, OR ONE MAJOR AND 2 MINOR CRITERIA PLUS EVIDENCE OF STREPT. INFECTION. Some considerations and precautions during diagnosis : If you considered carditis as a major criterion, you should not consider prolonged PR interval as a minor criterion. If you considered arthritis as a major criterion, you should not consider artharalgia as a minor criterion. You can t depend on both subcutaneous nodules and erythema marginatum only as 2 major criteria, as they are not pathognomonic to RF and occur in other collagen diseases. Investigation Acute phase reactants (ESR- CRP- leucocytosis) ASO titre. Throat culture for group A beta-haemolytic strept. ECG (prolonged PR). Plain X-ray (cardiomegaly- pericardial effusion). ECHO, important and diagnostic (detects pericardial effusion, and degree of valvular affection). 10

12 Treatment Curative treatment Bed rest for 3 weeks or till improvement of all symptoms and signs. Diet salt restriction in heart failure. Eradication of streptococcal infection BY: long acting penicillin u deep I.M. once, OR Penicillin procaine u only I.M. twice daily for 10 days, OR Oral penicillin v times daily for 10 days. Prophylactic treatment Long acting penicillin u every 2-4 weeks deep I.M., OR Penicillin V orally u twice daily, Or Erythromycin 250 mg twice daily orally. Duration Rh fever without carditis: 5yrs or 21yrs of age. Rh fever with carditis but without residual heart disease: 10yrsadulthood. Rh fever with carditis and residual heart disease: 10yrs at least since last episode and at least 40yrs of age. Prevention of subacute bacterial endocarditis Tonsillectomy if large with repeated infection. Sensitivity test must be done before any long acting penicillin is given. If the patient is sensitive to penicillin we give erythromycin 50 mg/kg/day orally for 10 days. 11

13 Treatment of rheumatic symptoms as carditis and arthritis Salicylates o Indications: rh fever without carditis. Rh fever with carditis but without cardiomegaly or congestive heart failure. o Dose: 100 mg/kg/day in 4 divided doses po for 3-5 days, followed by: 75mg/kg/d in 4 divided doses for 4 weeks. corticosteroids (prednisone) o Indications: rh fever with carditis. no response to salicylates. rh fever with heart failure. o Dose: 2mg/kg/day with gradual withdrawal. Duration for 2-4 weeks. Treatment of rheumatic chorea Phenobarbital. Haloperidol 1-5 mg /day orally divided in doses. Chlorpromazine. 12

14 Numerous authors have suggested that more changes in Jones criteria may be in order. For example, some have suggested that echocardiography should be performed in all suspected cases in order to avoid both under-diagnosis and over-diagnosis. Others suggest that cases are missed because some patients have only monoarthritis and not polyarthritis. They would like to see monoarthritis become a major criterion. These same authors suggest that the set point of fever at 38 o C might be too high. Others reported atypical cases in which arthritis involved small joints rather than large joints. Finally, they suggest that arthralgia should be changed from a minor to a major Jones criterion. COMPLICATIONS Valvular lesion. Infective endocarditis. Heart failure. Arrhythmias. PROGNOSIS OUTCOME Those with carditis as part of the initial episode are at greater risk of developing recurrences and of sustaining further cardiac injury. Worldwide, approximately 60% of all patients with ARF will develop rheumatic heart disease. Patients without carditis during the initial episode have a relatively low risk of developing carditis during recurrences. 13

15 An inverse relationship between severity of joint involvement and risk of carditis appears to exist. In approximately 75% of cases, the acute attack lasts only 6 weeks. Ninety percent of cases resolve in 12 weeks or less. Fewer than 5% of patients have symptoms that persist for 6 months or more.# Morbidity from acute rheumatic fever The mortality rate has declined steadily over the last 3 decades. A partial explanation for the decrease in mortality rate may be the increase in antibiotic use. In developing nations and lower socioeconomic areas where rheumatic fever is more prevalent. ARF is a major cause of death and disability in children and adolescents. (ARF) is directly proportional to the rate of streptococcal infections. Infections that are not treated adequately are most likely to cause the major sequelae. Morbidity also is related to the care that the patient receives. Cardiac involvement is the major cause of long-term morbidity. Valvular vegetations (endocarditis) are the cause of mitral valve regurgitation, the end result being left ventricular (LV) dilation and congestive heart failure (CHF). Myocarditis is present but not the cause of heart failure....end 14

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