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Prof. Pavlyshyn H.A.
ACUTE RHEUMATIC FEVER
DEFINITION
Rheumatic fever is an inflammatory process which can involve the joints, heart, skin and brain
It is caused by antibody cross reactivity and occurs 2-3 weeks after a Group A Streptococcal infection.
EPIDEMIOLOGY
470,000 new cases of Acute Rheumatic Fever/year
233,000 deaths due to Rheumatic Fever/yearMajority of deaths occur in developing countriesIncidence in the US: 2-14 cases/100,000Historically, there is a temporal relationship
between epidemics of streptococcal pharyngitis and scarlet fever with the epidemics of acute rheumatic fever
No clear gender predilection overall, but mitral stenosis and syndenham’s chorea occur more in females than males.
BACKGROUND
Primarily affects children between ages 5-12Generally occurs 2-3 weeks after Group A
Streptococcal infection (strep throat or scarlet fever)
In the US, Rheumatic fever has become fairly rare due to use of antibiotics to treat streptococcal infections
Globally, 3% of those with an untreated streptococcal infection develop rheumatic fever
40% of those with Acute Rheumatic Fever develop mitral stenosis as adults
BACKGROUND
Cutaneous streptococcal infections have not been shown to initiate Acute Rheumatic Fever.
Strains of certain M serotypes/genotypes of streptococci have higher associations than other genotypes
Epidemics of Acute Rheumatic Fever in Trinidad and Chile showed that streptococci causing Acute Rheumatic Fever belonged to different serotypes than those that cause Acute Glomerulonephritis.
PATHOPHYSIOLOGY
Exact mechanism of how Group A streptococcal infection causes Acute Rheumatic Fever is unknown however it is believed to be caused by a cross reactivity of antibodies
Suggested Theories Toxic effects of streptococcal products (streptolysin S
or O) which then cause direct tissue injury Serum Sickness-like reaction mediated by antigen-
antibody complexes Autoimmune phenomenon
PATHOPHYSIOLOGY
More support for an autoimmune phenomenon (Type II hypersensitivity reaction)
During strep infection, antigen presenting cells present bacterial antigen to helper T cells. These helper T cells then activate B cells to induce production of antibodies against the Streptococcal cell wall. These antibodies can also interact with other cells in the body (for example, myocardium or joints, etc) producing the symptoms responsible with acute rheumatic fever
PATHOGENESIS
Most patient have elevated antibody titers to at least one streptococcal antibody Streptolysin O Hyaluronidase Streptokinase
PATHOPHYSIOLOGY (CARDIAC)
Aschoff nodule with owl-eyed shape in the cross section and catapillar-shaped
in the longitudinal section
PATHOPHYSIOLOGY (CARDIAC)
Thickened fused chordae of the mitral valve
CLINICAL MANIFESTATIONS
Latent period: time between preceding streptococcal pharyngitis and Acute Rheumatic fever is about 19 days (range 1-5 weeks)
If initial complaint is polyarthritis, disease generally has more abrupt onset compared to if initial presentation is with myocarditis.
Arthritis occurs in 75% of initial attacks, carditis in 40-50% and chorea in 15% with subcutaneous nodules and erythema marginatum in <10%
CLINICAL MANIFESTATIONS (CARDITIS)
Usually manifests within the first 3 weeks of Acute Rheumatic Fever
Signs: new heart murmur, cardiomegaly, CHF, perciardial friction rub, effusions
Chronic inflammatory changes may lead to development of rheumatic heart disease.
Characteristic murmur or Rheumatic heart disease: mitral regurgitation Low-pitched mid diastolic flow murmur at the apex (Carey
Coombs murmur Aortic regurgitation
Can also get AV conduction delays
CARDITIS
Cardiomegaly
Cardiomegaly
primarily prolonged PR interval
AV conduction delays
CLINICAL MANIFESTATIONS (JOINTS)
Arthralgias and arthritis (may be migratory)
Warm, swollen, tender jointsUsually involves the knees, ankles,
elbows and wristsLasts 2-3 weeks
Arthralgias and arthritis
CLINICAL MANIFESTATIONS
Subcutaneous Nodules: usually associated with severe carditis and occur several weeks after onset. Firm, painless nodules (up to 2cm) found over bony
surfaces and tendons Occur near elbows, knees, wrists, achilles tendon,
vertebral joints Usually persist for 1-2 weeks
SUBCUTANEOUS NODULES
SUBCUTANEOUS NODULES
CLINICAL MANIFESTATIONS
Erythema Marginatum: nonpruritic, painless erythematous rash on trunk and/or proximal extremities Macular lesions with raised margins and
central clearing May last from weeks to months
ERYTHEMA MARGINATUM
CLINICAL MANIFESTATIONS
Sydenham’s Chorea: neurologic disorder with muscular weakness, emotional lability and involuntary, uncoordinated, purposeless movements Disappear during sleep Mainly occur in hands, feet and face Sensation intact Lasts 2-4 months
Sydenham’s Chorea
DIFFERENTIAL DIAGNOSIS
Poststreptococcal reactive arthritis: is non-migratory
Rheumatoid ArthritisSLEInfective endocarditisSickle Cell diseaseDrug reactionsTBLyme DiseaseSerum Sickness
DIAGNOSIS
JONES CRITERIA Developed by Dr. T Duckett Jones in 1944 Need 2 major criteria or 1 major and 2 minor criteria
in the presence of a prior strep infection to make the diagnosis
Evidence of prior strep infection with positive throat culture or antigen test, elevated streptococcal antibody titer, or history of rheumatic fever/heart disease
MAJOR CRITERIA
Migratory Polyarthritis: migrating arthritis with inflammation involving the large joints (knees, ankles, elbows, wrists) and typically affects the leg joints first
Carditis: can manifest with new murmur, pericarditis, congestive heart failure
Subcutaneous Nodules: a form of aschoff bodies. Are painless nodules on the back of the wrists, elbows, knees
Erythema Marginatum: rash beginning on the arms or trunk and spreads outward. Lesion with ring with central clearing. Worsens with heat. Does not involve the face
Sydenham’s Chorea (St. Vitus’ Dance): purposeless movements of the face and arms. Late finding
MINOR CRITERIA
FeverArthralgia: joint pain without inflammationElevated CRP, ESR or leukocytosisEKG changes: primarily prolonged PR
intervalEvidence of Group A Streptococcal infection
via elevated antistreptolysin O titer or DNAase
Prior history of rheumatic fever or heart disease
TREATMENT
Anti-inflammatory AgentsAntibioticsProphylaxis
ANTI-INFLAMMATORY AGENTS
Aspirin 4-8grams/day for adultsContinue anti-inflammatory therapy until ESR
or CRP are normalMay need steroids if there is cardiac
involvement to help prevent sequelae such as mitral stenosis
Corticosteroids, if indicated, are given at prednisone 2mg/kg/day for 2 weeks and then tapered
ANTIBIOTICS
Penicillin for at least 10 daysPenicillin 500mg BID-TIDCan use erythromycin for PCN allergic
patients (given at 40mg/kg/day given in 2-4 doses/day)
PROPHYLAXIS
Prophylaxis needed to prevent recurrence of Acute Rheumatic Fever
Start prophylaxis after acute episode resolvesCan use:
Penicillin V 250mg BID or, Sulfadiazine 1000mg daily, or Penicillin G 1.2 million units IM q4weeks For PCN allergic patients: erythromycin 250mg PO BID
Recurrence of disease generally occurs in the first couple years
PROPHYLAXIS
WHO GUIDELINES At least 5 years of prophylaxis or if child until age 18
if not cardiac involvement 10 years prophylaxis or if child until age 25 if has mild
mitral regurgitation Lifelong prophylaxis if has severe valve disease
Complications
Complications
Complications