ARF Flashcards
- multisystem disease resulting from an autoimmune reaction to infection with GAS
- cardiac valvular damage (rheumatic heart disease [RHD]), which may persist after the other features have disappeared
ARF
GLOBAL CONSIDERATIONS
- ARF and RHD are diseases of poverty
- RHD is the most common cause of heart disease in children in developing countries
- major cause of mortality and morbidity in adults
- 95% of ARF cases and RHD deaths now occur in developing countries
- ARF is mainly a disease of children age
- peaks between
- 5-14 years
- 25 and 40 years
ARF is exclusively caused by infection of the upper respiratory tract
with
GAS
appear to be associated with susceptibility
HLA-DR7 and HLA-DR4
class I] alleles have been associated with protection
- HLA-DRS,
- HLA-DR6,
- HLA-DR51,
- HLA-DR5S2,
- HLA-DQ
Associations have also been described with polymorphisms at the ___, high levels of circulating mannose-binding lectin, and Toll-like receptors
tumor necrosis factor a locus (TNF a-308 and TNF-a-238)
latent period of ARF
3 week (1-5 weeks)
Clinical Features of ARF
- Polyarthritis (60-75%)
- carditis (50-60%)
Erythema marginatum and subcutaneous nodules are now rare, being found in
<5% of cases
Up to 75% of patients with ARF progress to
RHD
hallmark of rheumatic carditis
Valvular damage
is almost always affected
mitral valve
characteristic manifestation of carditis in previously
unaffected individuals is ____, sometimes
accompanied by ____
- mitral regurgitation
- aortic regurgitation
WHF Criteria for Echocardiographic Dx of RHD in Individuals <20 y.o
DEFINITE RHD
- Pathologic MR and at least two morphologic features of RHD of the mitral valve
- MS mean gradient 4 mmHg (note: congenital MV anomalies must be
excluced) - Pathologic AR and at least two morphologic features of RHD of the AV note: bicuspid AV and dilated aortic root must be excluded
- Borderline disease of both the MV and AV
WHF Criteria for Echocardiographic Dx of RHD in Individuals <20 y.o
BORDERLINE RHD
- At least two morphologic features Of RHD of the MV without pathologic MR or MS
- Pathologic MR
- Patholorgic AR
WHF Criteria for Echocardiographic Dx of RHD in Individuals <20 y.o
NORMAL ECHOCARDIOGRAPHIC FINDINGS
ALL 4
- MR that does not meet all 4 Doppler criteria (physiologic MR)
- AR that does not meet all 4 Doppler criteria (physiologic AR)
- An isolated morphologic feature of RHD of the MV (e.g valvular thickening without any associated pathologic stenosis or regurgitation
- Morphologic feature of RMD of the AV (e.g valvular thickening) w/o any associated Pathologic Stenosis or regurgitation
most common form of joint involvement in ARF
Arthritis
- migratory, moving from one joint to another over a period of hours
- ARF almost always affects the large joints
- most commonly the knees, ankles, hips, and elbows—and is
asymmetric
Polyarthritis
commonly occurs in the absence of other manifestations
Sydenham’s chorea
- follows a prolonged latent period after group A streptococcal infection
- found mainly in females
- The choreiform movements affect particularly the head (causing characteristic darting movements of the tongue) and the upper limbs
- More than 50% of patients presenting with chorea will have carditis, for which reason echocardiography should be part of the workup
CHOREA
classic rash of ARF
erythema marginatum
painless, small (0.5—2 cm), mobile lumps beneath the skin
overlying bony prominences
Subcutaneous nodules
The most common serologic tests for Evidence of a preceding GAS infection
- anti-streptolysin O (ASO)
- anti-DNase B (ADB) titers
Diagnosis: initial ARF
2 major manifestations or 1 major plus
2 minor manifestations
Diagnosis: recurrent ARF
2 major or 1 major and 2 minor or
3 major
Major Criteria
- Low-risk populations
+ Carditis - Clinical and/or subclinical
+ Arthritis - Polyarthritis only
+ Chorea
+ Erythema marginatum
+ SC nodules
Minor Criteria
- Low-risk populations
+ Polyarthralgia
+ Fever (238.5°C)
+ ESR =60 mm in the first hour and/or
CRP 23.0 ma/dl
+ Prolonged PR interval, after
accounting for age variability (unless
carditis is a major criterion)
Test to Always request :
- Electrocardiogram (ECG)
- Echocardiogram
- Complete blood count (CBC)
- C-reactive protein (CRP)
- Streptococcal serology (antistreptolysin and anti-DNase B)
Tests to exclude alternative diagnoses, depending on clinical presentation and locally endemic infections
for Neisseria gonorrhoeae
Urine molecular test
Tests to exclude alternative diagnoses, depending on clinical presentation and locally endemic infections
Chlamydia trachomatis
Urine molecular test
Tests to exclude alternative diagnoses, depending on clinical presentation and locally endemic infections
for viral hepatitis, Yersinia spp., cytomegalovirus
(CMV), parvovirus 819, respiratory viruses, Ross River virus, Barmah
Forest virus
Serologic or other testing
is the drug of choice for ARF
Penicillin
- no proven value in the treatment of carditis or chorea
- At higher doses, the patient should be monitored for symptoms such as nausea, vomiting, or tinnitus
SALICYLATES AND NSAIDs
Drug of choice for Carditis or chorea
Aspirin
Is a suitable alternative to aspirin and has the advantage of twice-daily dosing
Naproxen
In patients with severe chorea, ___ is preferred to haloperidol.
carbamazepine or sodium valproate
Are effective and lead to more rapid symptom reduction in
chorea. They should be considered in severe or refractory cases.
corticosteroids
Untreated, ARF lasts on average
12 weeks
With treatment, patients are usually discharged from hospital within
1-2 weeks
inflammatory markers should be monitored every
1-2 weeks until
they have normalized (usually within 4-6 weeks)
should be performed after 1 month to determine if
there has been progression of carditis.
echocardiogram
if commenced within 9 days of sore throat onset, a course of ___ will prevent almost all cases of ARF that would otherwise have developed.
penicillin
SECONDARY PREVENTION
- best antibiotic for secondary prophylaxis
- can be given every 3 weeks, or even every 2 weeks, to persons considered to be at particularly high risk
benzathine penicillin G
AHA Recommendations for Duration of Secondary Prophylaxis
CATERGORY OF PX
- Rheumatic fever without carditis
For 5 years after the last attack or 21 years of age (whichever is longer)
AHA Recommendations for Duration of Secondary Prophylaxis
CATERGORY OF PX
- Rheumatic fever with carditis but no residual valvular disease
For 10 years after the last attack, or 21 y.o (whichever is longer)
AHA Recommendations for Duration of Secondary Prophylaxis
CATERGORY OF PX
- Rheumatic fever with persistent valvular disease, evident clinically or
On echocardiography
For 10 years after the last attack, or 40 years of age (whichever is longer);
Sometimes lifelong prophylaxis
