1 Rheumatic Fever. 2 ObjectivesObjectives Etiology Epidemiology Pathogenesis Pathologic lesions...
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Transcript of 1 Rheumatic Fever. 2 ObjectivesObjectives Etiology Epidemiology Pathogenesis Pathologic lesions...
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Rheumatic Fever
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ObjectivesObjectivesObjectivesObjectivesEtiologyEpidemiologyPathogenesisPathologic lesionsClinical manifestations & Laboratory
findingsDiagnosis & Differential diagnosisTreatment & PreventionPrognosisReferences
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EtiologyEtiologyAcute rheumatic fever is a systemic
disease of childhood,often recurrent that follows group A beta hemolytic streptococcal infection
It is a delayed non-suppurative sequelae to URTI with GABH streptococci.
It is a diffuse inflammatory disease of connective tissue,primarily involving heart,blood vessels,joints, subcut.tissue and CNS
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EpidemiologyEpidemiology
Ages 5-15 yrs are most susceptibleRare <3 yrsGirls>boysCommon in 3rd world countriesEnvironmental factors-- over
crowding, poor sanitation, poverty,Incidence more during fall ,winter &
early spring
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PathogenesisPathogenesis
Delayed immune response to infection with group.A beta hemolytic streptococci.
After a latent period of 1-3 weeks, antibody induced immunological damage occur to heart valves,joints, subcutaneous tissue & basal ganglia of brain
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Strains that produces rheumatic fever - M types l, 3, 5, 6,18 & 24
Pharyngitis- produced by GABHS can lead to- acute rheumatic fever ,
rheumatic heart disease & post strept. Glomerulonepritis
Skin infection- produced by GABHS leads to post streptococcal glomerulo nephritis only. It will not result in Rh.Fever or carditis as skin lipid cholesterol inhibit antigenicity
Group A Beta Hemolytic Streptococcus
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Diagrammatic structure of the group A beta hemolytic streptococcus
Capsule
Cell wall
Protein antigens
Group carbohydrate
Peptidoglycan
Cyto.membrane
Cytoplasm
…………………………………………………...
Antigen of outer protein cell wall of GABHS induces antibody response in victim which result in autoimmune damage to heart valves, sub cutaneous tissue,tendons, joints & basal ganglia of brain
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Pathologic LesionsPathologic LesionsFibrinoid degeneration of connective tissue,inflammatory edema, inflammatory cell infiltration & proliferation of specific cells resulting in formation of Ashcoff nodules, resulting in-
-Pancarditis in the heart-Arthritis in the joints-Ashcoff nodules in the subcutaneous tissue-Basal gangliar lesions resulting in
chorea
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Rheumatic Carditis Histology (40X)
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Histology of Myocardium in Rheumatic Carditis (200X)
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Clinical FeaturesClinical Features
Flitting & fleeting migratory polyarthritis, involving major joints
Commonly involved joints-knee,ankle,elbow & wrist
Occur in 80%,involved joints are exquisitely tender
In children below 5 yrs arthritis usually mild but carditis more prominent
Arthritis do not progress to chronic disease
1.Arthritis
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Clinical Features (Contd)Clinical Features (Contd)
Manifest as pancarditis(endocarditis, myocarditis and pericarditis),occur in 40-50% of cases
Carditis is the only manifestation of rheumatic fever that leaves a sequelae & permanent damage to the organ
Valvulitis occur in acute phaseChronic phase- fibrosis,calcification &
stenosis of heart valves(fishmouth valves)
2.Carditis
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Rheumatic heart disease. Abnormal mitral valve. Thick, fused chordae
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Another view of thick and fused mitral valves in Rheumatic heart disease
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Clinical Features (Contd)Clinical Features (Contd)
Occur in 5-10% of casesMainly in girls of 1-15 yrs ageMay appear even 6/12 after the attack of
rheumatic feverClinically manifest as-clumsiness,
deterioration of handwriting,emotional lability or grimacing of face
Clinical signs- pronator sign, jack in the box sign , milking sign of hands
3.Sydenham Chorea
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Clinical Features (Contd)Clinical Features (Contd)
Occur in <5%.Unique,transient,serpiginous-looking
lesions of 1-2 inches in sizePale center with red irregular marginMore on trunks & limbs & non-itchyWorsens with application of heatOften associated with chronic carditis
4.Erythema Marginatum
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Clinical Features (Contd)Clinical Features (Contd)
Occur in 10%Painless,pea-sized,palpable nodulesMainly over extensor surfaces of
joints,spine,scapulae & scalpAssociated with strong seropositivityAlways associated with severe carditis
5.Subcutaneous nodules
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Clinical Features (Contd)Clinical Features (Contd)
Other features (Minor features)
Fever-(upto 101 degree F)ArthralgiaPallorAnorexiaLoss of weight
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Laboratory FindingsLaboratory Findings
High ESRAnemia, leucocytosisElevated C-reactive protienASO titre >200 Todd units.
(Peak value attained at 3 weeks,then comes down to normal by 6 weeks)
Anti-DNAse B test Throat culture-GABHstreptococci
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Laboratory Findings (Contd)Laboratory Findings (Contd)ECG- prolonged PR interval, 2nd or 3rd
degree blocks,ST depression, T inversion
2D Echo cardiography- valve edema,mitral regurgitation, LA & LV dilatation,pericardial effusion,decreased contractility
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DiagnosisDiagnosis
Rheumatic fever is mainly a clinical diagnosis
No single diagnostic sign or specific laboratory test available for diagnosis
Diagnosis based on MODIFIED JONES CRITERIA
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Recommendations of the American Heart Association
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Exceptions to Jones CriteriaExceptions to Jones Criteria
Chorea alone, if other causes have been excluded
Insidious or late-onset carditis with no other explanation
Patients with documented RHD or prior rheumatic fever,one major criterion,or of fever,arthralgia or high CRP suggests recurrence
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Differential DiagnosisDifferential Diagnosis
Juvenile rheumatiod arthritisSeptic arthritisSickle-cell arthropathyKawasaki diseaseMyocarditisScarlet feverLeukemia
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TreatmentTreatmentStep I - primary prevention
(eradication of streptococci)Step II - anti inflammatory treatment
(aspirin,steroids)Step III- supportive management &
management of complicationsStep IV- secondary prevention
(prevention of recurrent attacks)
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STEP I: Primary Prevention of Rheumatic Fever (Treatment of Streptococcal Tonsillopharyngitis) Agent Dose Mode Duration
Benzathine penicillin G 600 000 U for patients Intramuscular Once 27 kg (60 lb) 1 200 000 U for patients >27 kg
or Penicillin V Children: 250 mg 2-3 times daily Oral 10 d (phenoxymethyl penicillin) Adolescents and adults:
500 mg 2-3 times daily
For individuals allergic to penicillin
Erythromycin: 20-40 mg/kg/d 2-4 times daily Oral 10 d Estolate (maximum 1 g/d)
or Ethylsuccinate 40 mg/kg/d 2-4 times daily Oral 10 d
(maximum 1 g/d)
Recommendations of American Heart Association
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Step II: Anti inflammatory treatmentClinical condition Drugs
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Bed rest Treatment of congestive cardiac failure:
-digitalis,diureticsTreatment of chorea:
-diazepam or haloperidol Rest to joints & supportive splinting
3.Step III: Supportive management & management of complications
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STEP IV : Secondary Prevention of Rheumatic Fever (Prevention of Recurrent Attacks)
Agent Dose Mode
Benzathine penicillin G 1 200 000 U every 4 weeks* Intramuscular
orPenicillin V 250 mg twice daily Oral
orSulfadiazine 0.5 g once daily for patients 27 kg (60 lb Oral
1.0 g once daily for patients >27 kg (60 lb)
For individuals allergic to penicillin and sulfadiazineErythromycin 250 mg twice daily Oral
*In high-risk situations, administration every 3 weeks is justified and recommended
Recommendations of American Heart Association
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Duration of Secondary Rheumatic Fever Prophylaxis
Category DurationRheumatic fever with carditis and At least 10 y since last residual heart disease episode and at least until (persistent valvar disease*) age 40 y, sometimes lifelong
prophylaxis Rheumatic fever with carditis
10 y or well into adulthood, but no residual heart disease whichever is longer (no valvar disease*)
Rheumatic fever without carditis 5 y or until age 21 y,
whichever is longer*Clinical or echocardiographic evidence.
Recommendations of American Heart Association
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PrognosisPrognosis
Rheumatic fever can recur whenever the individual experience new GABH streptococcal infection,if not on prophylactic medicines
Good prognosis for older age group & if no carditis during the initial attack
Bad prognosis for younger children & those with carditis with valvar lesions