ACUTE RHEUMATIC FEVER

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ACUTE RHEUMATIC FEVER
Definition
Current Diagnosis 07
• An acute systemic immune disease that may
develop after an infection with Group A betahemolytic Streptococcal infection of the pharynx.
• This disease can affect the HEART, JOINTS,
SKIN, SUBCUTANEOUS TISSUE, BRAIN,
RESPIRATORY SYSTEM, VESSELS,
SEROSAL MEMBRANES, TENDONS AND
FASCIAL SHEATHS
GENERAL CONSIDERATIONS
• Usually preceded – 2-3 weeks (1-5 weeks)
by sore throat.
• Peak incidence 5- 15 years.
Rare in <4 year olds and > 40 years
3% of pt dev ARF
PATHOLOGY
The Aschoff bodies comprises a localised
area of inflammation having a central
deposit of amorphous fibrinoid material
surrounded by an inflammatory
infiltrate of mesenchymal cells known
as Anitschkow giant cells or “caterpillar
cells” (because the chromatin is
distributed in the centre of the nucleus
in the forrm of a slender wavy ribbon
that resemles the attenuated body with
innumerable fine leg like projections )
and an occasional multinucleated Aschoff
giant cell with”owl eyed” nucleoli
Fully developed Aschoff bodies are
pathognomonic of RF
Aschoff bodies proceed thru 3 phasesexudative, proliferative and healed
The heart has been sectioned to reveal the mitral valve as seen from above in the
left atrium. The mitral valve demonstrates the typical "fish mouth" shape with
chronic rheumatic scarring. Mitral valve is most often affected with rheumatic
heart disease, followed by mitral and aortic together, then aortic alone, then
mitral, aortic, and tricuspid together.
Microscopically, acute rheumatic carditis is marked by a peculiar form
of granulomatous inflammation with so-called "Aschoff nodules"
seen best in myocardium. These are centered in interstitium around
vessels
as shown here. The myocarditis may be severe enough to cause
congestive heart failure.
Here is an Aschoff nodule at high magnification. The most
characteristic component is the Aschoff giant cell. Several appear here
as large cells with two or more nuclei that have prominent nucleoli.
Scattered inflammatory cells accompany them and can be
mononuclears or occasionally neutrophils.
Another peculiar cell seen with acute rheumatic carditis is the
Anitschkow myocyte. This is a long, thin cell with an elongated
nucleus.
MODIFIED JONES’ CRITERIA
MAJOR:
• Polyarthritis
• Carditis
• Chorea
• Subcutaneous nodules
• Erythema marginatum
MINOR CRITERIA
Clinical
• Fever
• Polyarthralgia
• h/o previous ARF or Rheum. heart disease
Lab
• Reversible prolongation of PR interval
• Inc ESR
• Inc C Reactive Protein
• + throat culture Or rapid streptococcal antigen
test
• Inc ASO titre
POLYARTHRITIS
• Migratory – flitting and fleeting
• Involves large joints sequentially
• Polyarthritis- in adults only a single joint may be
affected
• Lasts 1-5 weeks
• Occurs in 75% or patients
• Subsides without residual deformity
• Dramatic response of arthritis to therapeutic
doses of aspirin or NSAIDs
CARDITIS
•
•
•
1.
Most likely in children and adolescents
Occurs in 1/3 of cases
Any of the following signs suggest the presence of carditis
Endocardial- MR or AR murmurs indicative of dilatation of valve ring with or without associated valvulitis
-Short mid-diastolic murmur (Carey-Coombs) may be present
- Changing quality of heart sounds
2. Myocardial
- Tachycardia even at rest. Arrhythmias or ectopic beats
- Cardiomegaly- on physical exam, CXR or ECHO
- Congestive cardiac failure – right or left sided
3. Pericardial
- Pericarditis
- Pericardial effusion
ECG Changes
- Changing contour of P waves
- Inversion of T waves
- Prolongation of PR interval
Maybe self limiting or may lead to slowly progressive valvular deformity
Mitral valve attacked in 75% cases, aortic in 30% ( but rarely as the sole valve), tricuspid and
pulmonary in < 5% cases
SYDENHAM’S CHOREA
• Involuntary choreo- athetoid movements
primarily of the face, tongue, and upper
extremities
• Maybe sole manifestation- in 50% of
cases no other signs of RF
• Girls more frequenty affected
• Rare in adults
• Lease common(<3%) but most diagnostic
of the manifestations of RF
Erythema Marginatum
• Rapidly enlarging
macules that assume
the shape of rings or
crescents with clear
centres
• They may be raised,
confluent and either
transient or
persistent.
Subcutaneous Nodule
• Uncommon except in
children
• Small (<2cm in diameter)
firm & nontender
• Attached to fascia, or
tendon sheaths over bony
prominences
• Persist for days or weeks
• Are recurrent
• Indistinguishable from
rheumatoid nodules
•
•
•
•
•
“Also there” features:
Pneumonia
Epistaxis
Erythema nodosum
Abdominal pain
REQUIRED FOR DIAGNOSIS
• Two major criteria OR
• One major and two minor criteria
DIFFERENTIAL DIAGNOSIS
•
•
•
•
•
•
•
•
Rheumatoid arthritis
Osteomyelitis
Endocarditis
Chronic meningiococcemia
SLE
Lyme disease
Sickle cell disease
Surgical abdomen
TREATMENT
PHARYNGITIS
Benzathene penicillin 1.2 million units ( 50,000 units/kg to a max of 1.2 million units) is
injected IM once or
Inj Procaine penicillin 600,000 units once daily for 10 days
Erythromycin can be substituted ( 40mg/kg/day)
CARDITIS
• Bed rest – until temp, ESR, resting pulse rate and ECG have all returned to normal
• Prednisone if there is CCF or cardiomegaly
POLYARTHRITIS
• Anti inflammatory agent - Aspirin markedly reduces fever, joint pain and swelling
• No effect on the natural course of the disease
• 100mg / kg/day in 4-6 divided doses. Can be reduced to 75mg/Kg/day once there is a
response . Given for 4-6 weeks
• Toxicity includes- tinnitus, vomiting and GI bleeding.
• When response to aspirin is inadequate a short course of prednisone (1 mg/kg/day)
orally daily usually causes rapid improvement of joint symptoms. It is tapered over 2
weeks. Add aspirin when tapering begins.
PREVENON OF ARF-PRIMARY
• Early and adequate treatment of
Strep. throat infections with a penicillin or
Azithromycin will prevent Rheumatic Fever
• Avoidance of overcrowding & improved
hygiene will decrease the incidence of
pharyngitis
PREVENTION -SECONDARY
Those who have had RF can have recurrences
Recurrences are most common in children and in those patients who have had
carditis during their initial episode of RF
Recurrences are prevented by giving Benzathine penicillin 1.2million units IM
every 4 week
OR
Oral penicillin 250 mg bid
Erythromycin 250 mg bid
Azithromycin
Duration controversial:
5 years after last attack or at 25 years, whichever is later
(earlier recommendation: life-long)
Those with cardiac involvement and in high risk group- military personnel,
health staff, school teachers, parents of young children- life long prophylaxis
IMPORTANT!!
The complication of untreated, or
inadequately treated Acute rheumatic
fever is
RHEUMATIC HEART DISEASE
RHEUMATIC HEART DISEASE
• Results from single or repeated attacks of RF
• Rigidity and deformity of valves resulting in
stenosis or incompetence or both
• Mitral valve alone in 50%
• Mitral + Aortic in 25%
• Pure aortic uncommon
• History of RF obtained in 60%
• Should receive prophylatic penicillin monthlyand
preceding dental extractions,urologic and
surgical procedures to prevent endocarditis
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