PEADS_-_CVS_-_ACUTE_RHEUMATIC_FEVER(0).pptx

PEADS_-_CVS_-_ACUTE_RHEUMATIC_FEVER(0).pptx

1. ACUTE RHEUMATIC FEVER

2. ACUTE RHEUMATIC FEVER Definition Rheumatic fever (RF) is a delayed nonsuppurative sequelae to upper respiratory infection with group A β hemolytic streptococci. It is a diffuse inflammatory disease of the connective tissue that involves principally the heart‚ blood vessels‚ joints‚ central nervous system‚ and subcutaneous tissues . The term acute rheumatic fever is a misnomer because it may not be acute‚ rheumatic‚ or febrile. Although the term emphasizes involvement of the joints, the disease owes its importance to involvement of the heart. As early as 1884, Lasegue described this feature: “Rheumatic fever is a disease that licks the joints but bites the heart .”

3. ACUTE RHEUMATIC FEVER Definition Rheumatic fever appears to be an immunologic disorder initiated by Group A beta hemolytic streptococcus . Antibodies produced against some streptococcal cell wall proteins and sugars react with the connective tissues of the body as well as the heart and result in rheumatic fever. There is no single test for the confirmation of diagnosis. There is a strong relationship with streptococcal infection and it is possible to prevent rheumatic fever by preventing streptococcal infection through the use of Penicillin .

4. ACUTE RHEUMATIC FEVER B. Etiology and Pathophysiology GAS infection is the etiologic precursor of ARF but host and environmental factors are important. GAS M proteins share epitomes (antigenic-determinant sites that are recognized by antibodies) with proteins found in synovium‚ heart muscle‚ and heart valve ‚ suggesting that molecular mimicry contributes to the arthritis‚ carditis‚ and valvular damage. Genetic host factors include the D8/17B cell antigen and certain class II histocompatibility antigens. Malnutrition, overcrowding and lower socioeconomic status predispose to streptococcal infections and subsequent episodes of rheumatic fever. The joints‚ heart‚ skin‚ and CNS are most often affected. Pathology varies by site.

5. B. Etiology and Pathophysiology (Cont’d) A strong association with beta hemolytic streptococci of group A is indicated by a number of observations: A history of preceding sore throat is available in approximately 50% of patients. Epidemics of streptococcal infection are followed by a higher incidence of rheumatic fever. The seasonal variation of rheumatic fever and streptococcal infection are identical. In patients with established rheumatic heart disease, streptococcal infection is followed by recurrence of acute rheumatic fever. Penicillin prophylaxis for streptococcal infection prevents recurrences of rheumatic fever. More than 85% of patients with acute rheumatic fever consistently show elevated levels of anti-streptococcal antibody titers. Following streptococcal sore throat there is a latent period of 10 days to several weeks before the onset of rheumatic fever.

6. ACUTE RHEUMATIC FEVER C . Epidemiology Rheumatic heart disease constitutes from 16.5 to 50 percent of the cardiac patients in a hospital .   Age & Sex: The commonest age group involved is 5 to 15 years. The sexes are nearly equally affected, mitral valve disease and chorea are more common in females whereas aortic valve involvement is seen more often in males . Predisposing factors: Poor socioeconomic conditions leading to unhygienic living conditions and overcrowded households are predisposing factors since they help spread streptococcal infections. Under and poor nutrition by altering the immunological responses may be a factor in increasing the susceptibility.

7. ACUTE RHEUMATIC FEVER C . Clinical features & diagnosis The classical clinical picture of rheumatic fever consists of streptococcal sore throat with fever followed 10 days to a few weeks later by recurrence of fever and the various manifestations of acute rheumatic fever. The history of sore throat is available in less than 50% of the patients. Guidelines for the clinical diagnosis of acute rheumatic fever, originally suggested by Dr. T. Duckett Jones , were subsequently revised by the American Heart Association in 1965. The guidelines consist of major, minor and essential criteria . TWO MAJOR OR ONE MAJOR & TWO MINOR CRITERIA ARE REQUIRED IN THE PRESENCE OF ESSENTIAL CRITERIA TO DIAGNOSE ACUTE RHEUMATIC FEVER. It is important to emphasize that these guidelines are meant to help a physician in making a firm diagnosis of rheumatic fever and DO NOT MEAN THAT A PHYSICIAN SHOULD NOT USE HIS CLINICAL JUDGEMENT IN DIAGNOSING ACUTE RHEUMATIC FEVER IN THE ABSENCE OF THESE CRITERIA ( Table below ).

8. TABLE: Criteria for the diagnosis of acute rheumatic fever Major criteria Carditis Arthritis Subcutaneous nodules Chorea Erythema marginatum   Minor criteria Clinical Fever Arthralgia Previous rheumatic fever or rheumatic heart disease Laboratory Acute phase reactants: Leukocytosis, elevated sedimentation rate (ESR) & C reactive protein. Prolonged PR interval in electrocardiogram .   Essential criteria : Evidence for recent streptococcal infection as indicated by : Increased antistreptolysin ‘O’ titer Positive throat culture Recent scarlet fever .  

9. MAJOR CRITERIA 1. Carditis The rheumatic carditis is a pancarditis involving the pericardium, myocardium and the endocardium. Carditis occurs in 50 to 60% of patients of ARF. It is an early manifestation of rheumatic fever so that by the time a patient seeks help he already has evidence of carditis. Almost 80% of those patients who develop carditis do so within the first two weeks of the onset of rheumatic fever .

10. MAJOR CRITERIA 2. Arthritis Rheumatic arthritis is a polyarthritis involving large joints like knees, ankles and elbows. Uncommonly, smaller joints may also be involved. It is migratory polyarthritis with the affected joint showing redness, warmth, swelling, pain and limitation of movement. It is an early manifestation and occurs in 70 to 75% of cases , according to western literature. The pain and swelling appear rather quickly, last 3 to 7 days and subside spontaneously to appear in some other joint. There is no residual damage to the joint.

11. MAJOR CRITERIA 3. Subcutaneous nodules. Subcutaneous nodules appear on bony prominences like elbows, shins (Dict.: the front of the leg between the knee and the ankle ), occiput and spine . They vary in size from pinhead to an almond (Dict.: an oval edible nut. [from Greek]). They are non-tender. Subcutaneous nodules are a late manifestation and appear around 6 weeks after the onset of rheumatic fever though they have been described as early as 3 weeks from the onset. They occur in about 5 to 20% of cases of rheumatic fever in India (In Zed???). Patients who have subcutaneous nodules almost always have carditis. They last from a few days to weeks but have been known to last for almost a year.

12. MAJOR CRITERIA 4 . Chorea Sydenham’s chorea is also a late manifestation occurring about three months after the onset of acute rheumatic fever. Generally, by the time a patient manifests chorea, the signs of inflammation in the form of elevated sedimentation rate have returned to normal. Chorea consists of purposeless, jerky movements resulting in deranged speech, muscular incoordination, awkward gait and weakness. The affected child is emotionally disturbed and drops things she or he is carrying. It is three to four times more common in females as compared to males. Untreated , it has a self-limiting course of two to six weeks .

13. MAJOR CRITERIA 5. Erythema marginatum Although considered to be more specific than other varieties of skin manifestations, it is known to be extremely rare in Indians (In Zed???). The rash is faintly reddish, not raised above the skin and non-itching. It starts as a red spot with a pale center, increasing in size to coalesce with adjacent spots to form a serpiginous outline. We believe that the inability to recognize erythema marginatum is not because it does not occur but because of the dark complexion of the skin. Anyone who has seen erythema marginatum would recognize the futility of searching for it in a dark complexioned person. It is an early manifestation , predominantly seen over the trunk .

14. MINOR CRITERIA The minor criteria have been sub-divided into (A) clinical and (B) laboratory manifestations . A. Clinical Fever. Rheumatic fever is almost always associated with fever. The temperature rarely goes above 39.5°C. In the initial attack, it is present in almost 90% of the patients. Arthralgia. Arthralgia is defined as subjective pain whereas arthritis means subjective symptoms as well as objective signs of joint inflammation. Whereas arthritis is a major manifestation, arthralgias are a minor manifestation. Figures from India (In Zed???) indicate that arthritis and arthralgias together occur in about 90% of the patients. Previous rheumatic fever or rheumatic heart disease. This minor criterion is applicable only for a second attack of rheumatic fever.

15. MINOR CRITERIA B. Laboratory manifestations Acute phase reactants. Acute phase reactants consist of polymorphonuclear leukocytosis , increased sedimentation rate and presence of C-reactive protein . C-reactive protein is a beta globulin that is increased uniformly in all patients of acute rheumatic fever. It subsides rapidly if a patient is on steroids. Absence of C-reactive protein is strongly against the diagnosis of acute rheumatic fever. Presence of C-reactive protein, however, is not diagnostic since it becomes positive in many respiratory infections. Prolonged PR interval in the electrocardiogram. Prolonged PR interval is also a non-diagnostic criterion since it can get prolonged in many infections.

16. ESSENTIAL CRITERIA The essential criteria include evidences for recent streptococcal infection. The best of these is the presence of antibodies against the streptococci. The commonest in use is the antistreptolysin ‘O’ titer (ASO). Elevated levels of ASO only indicate previous streptococcal infection and not rheumatic fever. Rising titers of ASO is a strong evidence for a recent streptococcal infection.

17. Treatment There is no specific treatment. Management is symptomatic combined with suppressive therapy . Symptomatic therapy Bed rest – All patients with ARF should be kept on bed rest and in those with carditis, the bed rest should be prolonged until all evidence of activity subsides. Diet – S alt restriction is not necessary unless CCF is present. Penicillin – After obtaining throat culture, the patient should be put on penicillin. Initially the patient is given therapeutic doses of penicillin – 400,000 units of procaine penicillin, intramuscularly, twice daily for 10 days. This is followed by prophylactic penicillin using Benzathine penicillin 1.2 mega units every 21 days, 0.6 mega units every 15 days depending on the patient’s built. A six-year-old child weighing 15-16 kg may not have enough muscle mass to accept a 1.2 mega unit dose .

18. Treatment Suppressive therapy Aspirin or steroids are given as suppressive therapy. Since untreated rheumatic fever subsides in 12 wks. in 80% of the patients, EITHER of the two suppressive agents is given for 12 wks. Steroids are a more potent suppressive agent compared to aspirin. However, there is no proof that the use of steroids results in less cardiac damage as compared to aspirin. A number of observations indicate that steroids act faster and are superior at least in the initial phase. In selecting the suppressive drug for an individual patient, we follow the following guidelines. If a patient has: Carditis with CCF : Use steroids. It is mandatory . Carditis without CCF : one may use either steroids or aspirin ; however, we would almost always use steroids. If the patient does not have carditis , it is preferable to use aspirin.

19. Treatment Suppressive therapy The total duration of the course for the suppressive agent, aspirin or steroid, is 12 wks. With aspirin, the full doses are given for 10 weeks and then tapered off in the next two weeks. Full doses of steroids are given for three weeks and then tapered very gradually in the next nine weeks. The steroid most commonly used is prednisone. The dose is 60 mg/day for patients weighing more than 20 kg and 40 mg/day for patients weighing less than 20 kg. Following this, the reduction in dose is by 5 mg/week until it is finished. The dose of aspirin is 90 to 120 mg/kg/day in four divided doses. If facilities for blood salicylate level estimation are available, the dose is modified to maintain a blood salicylate level of 20 to 25 mg per dL.

20. Treatment Management of CCF Already dealt with earlier (see above) . Management of chorea As indicated earlier chorea is a late manifestation . By the time a patient presents as chorea the sedimentation rate as well as the ASO may be normal. The patient as well as the parents should be reassured and told about the self-limiting coarse of the disease . The patient should be provided complete physical & mental rest . Phenobarb, 30 mg thrice daily may be prescribed. Other drugs like Chlorpromazine, Valium, Diphenhydramine (Benadryl) or Promethazine (phenergan) can also be used to provide sedation.

21. Treatment Management of chorea (Cont ’d) Although aspirin and steroids are supposed not to have a place in the management of chorea, we have seen a dramatic response in some patients who were put on steroids and were not doing well on a combination of chlorpromazine and phenobarbitone. Long-term follow up studies in patients of chorea have shown appearance of heart disease in 20% of patients in twenty years and in 30% of patients in thirty years. As such, penicillin prophylaxis is essential to prevent recurrence of rheumatic fever.

22. Prevention of rheumatic fever It would be ideal to provide primary prevention of rheumatic fever . Primary prevention – Treatment of sore throat Secondary prevention – With benzathine penicillin (1.2 mega units / 3 wkly ). Primary prevention requires identification of streptococcal sore throat and its treatment with penicillin. It depends on the awareness of parents regarding dangers of sore throat. For primary prevention, it is necessary to educate the community regarding the consequences (dangers) of streptococcal sore throat . Logistically, it is difficult since it requires identification of sore throat which is dependent on education of parents, rapid laboratory confirmation of streptococcal infection of the throat and medical help and availability of penicillin.  

23. Prevention of rheumatic fever Secondary prevention consists in giving long acting benzathine penicillin. The dose is 1.2 mega units once every 3 weeks or 0.6 mega units every alternate week. The injection is painful and some patients get fever for 24 to 36 hours following the injection. As such, it is preferable to give the injection on a Saturday afternoon to avoid loss of studies for the child. Ideally, penicillin prophylaxis should continue for life long. Less than the ideal would be to continue it until the age of 35 years. The least satisfactory approach is to give it for 5 years from the last attack of rheumatic fever. The responsibility of continuing prophylactic penicillin belongs to the parents; however, unless a physician takes time in explaining the seriousness of the problem and the necessity of continuing penicillin on a long-term basis, the physician has done his job inadequately.