Download Recommended Duration of Prophylaxis for Rheumatic Fever

Fifth stage
‫ خليل‬.‫د‬
Pediatric
Lec-4
23/11/2016
Acquired Heart Diseases
Acute rheumatic fever; cardiomyopathies; cardiovascular infections, including myocarditis
and infective endocarditis; and non congenital valvular heart disease are the most common
acquired heart diseases among the pediatric age group patients.
Rheumatic Fever
Definition
Rheumatic fever is a delayed autoimmune reaction in genetically predisposed individuals
to group A, β-hemolytic, streptococcal pharyngitis. It is a self-limited disease that may
involve joints, skin, brain, serous surfaces, and the heart Despite the dramatic nature of
the acute episode, ARF leaves no lasting damage to the brain, joints or skin.
Epidemiology
 The incidence of acute rheumatic fever is 3 to 61 per 100,000 school children.
 ARF is predominantly a disease of children aged 5-14 years and generally does not
affect children less than 3 years old or adults.
 Acute rheumatic fever is most common during winter and spring, a seasonal variation
similar to that of streptococcal pharyngitis.
Clinical manifestation
•
Acute rheumatic fever is diagnosed using the revised Jones criteria, which consist of
clinical and laboratory findings.
• The presence of either two major criteria or one major and two minor criteria, along
with evidence of an antecedent streptococcal infection, confirm a diagnosis of acute
rheumatic fever.
• The infection often precedes the presentation of rheumatic fever by 2 to 6 weeks.
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Supporting evidence of a preceding streptococcal infection
1.
2.
3.
4.
Elevated or rising antistreptolysin-O or other streptococcal antibody, or
Rapid antigen test for group A streptococci, or
A positive throat culture, or
Recent scarlet fever.
Laboratory Findings
1. High ESR.
2. Anemia, leucocytosis .
3. Elevated C-reactive protein.
4. ASO titre >200 Todd units
5. Anti-DNAse B test .
6. Throat culture-GABH streptococci.
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7. ECGprolonged PR interval,
2nd or 3rd degree blocks ,
ST depression or T inversion.
8. 2 D Echo cardiography –
valve edema ,mitral regurgitation, LA & LV
dilatation ,pericardial effusion ,decreased
contractility.
Management
1. Benzathine penicillin G, 0.6 to 1.2 million units intramuscularly, is given to eradicate
streptococci. This serves as the first dose of penicillin prophylaxis as well .
In patients allergic to penicillin, erythromycin, 40 mg/kg per day in two to four doses for
10 days, may be substituted for penicillin.
2. Bed rest of varying duration is recommended. The duration depends on the type and
severity of the manifestations and may range from a week (for isolated arthritis) to
several weeks for severe carditis. Bed rest is followed by a period of indoor ambulation
of varying duration before the child is allowed to return to school.
3. Therapy with anti-inflammatory agents should be started as soon as acute rheumatic
fever has been diagnosed as follows.
Prednisone, 2 mg/kg/24 hours in 4 divided doses.
Aspirin, 100 mg/kg/d in4-6 divided doses.
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4. Treatment of CHF includes the following:
a. Complete bed rest with O2.
b. Prednisone for severe carditis of recent onset
c. Digoxin, used with caution, beginning with half the usual recommended dose,
because certain patients with rheumatic carditis are supersensitive to digitalis.
d. Furosemide,1 mg/kg every 6 to 12 hour.
5. Management of Sydenham's chorea:
a. Reduce physical and emotional stress.
b. For severe cases, any of the following drugs may be used: phenobarbital , haloperidol
,valproic acid, chlorpromazine (Thorazine), diazepam (Valium), or steroids.
Prevention (prophylaxis)
A patient who has had acute rheumatic fever is susceptible to recurrent rheumatic fever for
the rest of his life.
Recommended Duration of Prophylaxis for Rheumatic Fever
Category
Rheumatic fever
without carditis
Rheumatic fever with
carditis but without
residual heart disease (no
valvular disease)
Duration
At least for 5 yr or
until age 21 yr,
whichever is longer
At least for 10 yr or well
into adulthood, whichever
is longer
Rheumatic fever with
carditis and residual heart
disease (persistent valvular
disease)
At least 10 yr since last
episode and at least until
age 40 yr; sometimes
lifelong prophylaxis
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Cardiomyopathies
Primary myocardial disease, or cardiomyopathy, is a disease of the heart muscle itself, not
associated with congenital, valvular, or coronary heart disease or systemic disorders.
Cardiomyopathy has been classified into three types based on anatomic and functional
features: hypertrophic, dilated (or congestive), and restrictive
Features of different types
Feature
Hypertrophic
Dilated
Restrictive
Etiology
Inherited (AD in about
50%) Sporadic (new
mutation ±)
Pluricausal (e.g.,
toxic, metabolic,
infectious, alcohol,
doxorubicin)
Myocardial fibrosis,
hypertrophy, or
infiltration (amyloid,
hemochromatosis)
Hemodynamic
dysfunction
Diastolic dysfunction
(rigid ventricular walls
impede ventricular
filling)
Systolic contractile
dysfunction (↓
cardiac output, ↓
stroke volume, ↑
LVEDP)
Diastolic dysfunction
(with normal systolic
function) (abnormally
stiff LV with impaired
ventricular filling)
Symptoms
Infants, frequently
present with signs of
CHF .
Older children may be
asymptomatic, with
sudden death as the
initial presentation.
Dyspnea, fatigue, chest
pain, syncope or nearsyncope, and
palpitations may be
present.
signs and symptoms Exercise
intolerance,
of inadequate cardiac weakness and dyspnea,
output and CHF.
or chest pain.
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Feature
On examination
Hypertrophic
Dilated
Restrictive
A murmur is heard in Features of CHF. Rales
more than 50% of
may be audible on
children.
pulmonary
auscultation. Heart
sounds may be muffled,
and S3 is often present.
Concurrent infectious
illness may result in
circulatory collapse and
shock in children with
dilated
cardiomyopathies
Thickened LV (and
Biventricular dilatation
occasionally RV) wall and ↓ EF%
Jugular venous
distention, gallop
rhythm, and a systolic
murmur of AV valve
regurgitation may be
present.
Electrocardiography
(LVH), ST-T changes,
and abnormally deep
Q waves (owing to
septal hypertrophy)
Sinus tachycardia, LVH,
and ST-T changes are
the most common
findings.
Atrial hypertrophy. It
may show atrial
fibrillation and
paroxysms of
supraventricular
tachycardia.
Chest x ray
Mild left ventricular
enlargement with a
globular-shaped
heart.
Generalized
cardiomegaly is usually
present, with or
without signs of
pulmonary venous
hypertension or
pulmonary edema.
cardiomegaly,
pulmonary venous
congestion, and
occasional pleural
effusion.
Treatment
-β-Adrenoreceptor
blockers
-Vasodilator therapy
-Diuretics
-Digitalis plus diuretics
-Anticoagulants (±)
-β-Adrenoceptor
blockers (±)
Antiarrhythmics (±)
Cardiac transplantation
(±)
-Corticosteroids (±)
Echocardiography
-Calcium antagonists
-(Digitalis/catechols
,Diuretics and
nitrates are
contraindicated).
Biatrial enlargement
-Permanent
pacemaker for
advanced heart block
(±)
-Cardiac
transplantation (±)
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