Rheumatic Fever & Rheumatic Heart Disease
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Transcript Rheumatic Fever & Rheumatic Heart Disease
Rheumatic Fever & Rheumatic
Heart Disease
Rheumatic Fever
•Rheumatic fever (RF) is an acute, immunologically
mediated, multisystem inflammatory disease that occurs a
few weeks following an episode of group A streptococcal
pharyngitis.
•Major involvement of systemic connective tissue, it often
violate connective tissue of heart, joint, skin, and
subcutaneous and vascular connective tissue. Key
pathologic features is Rheumatic Granuloma.
•It occurs in children in age 5 to 15 years, 20% -adults
•The clinical course of rheumatic fever involves a
childhood infection with complications in adulthood
(cardiac defect).
Etiology and pathogenesis
It is an immune response associated with
streptococcal infection, but it is not caused
by bacteria directly effects.
The evidence related with group A β-hemolytic
streptococcus infection including:
1. There is a streptococcus infection history before
the onset of RF.
2. A variety of antibodies of the streptococcus and
its products can be detected in the onset phase.
serous "O" antibody in 95% patients is high, >
500 units.
3. Regional distribution consistent with area of
streptococcal infection.
4. Antibiotic prophylaxis treatment is effective.
The evidence which is not directly caused by
streptococcus infection including:
1. The disease is not appeared in infected at the
time, but in 2-3 weeks later, it is in line with
emergence period of the general immune
response.
• No evidence of direct invasion of organ by
streptococcus.
• Streptococcus has never been found in the RF
patient's blood .
• Not purulent inflammation, but the fibrinoid
necrosis.
Antigen and antibody cross-reactivity:
The antigens of streptococcus may stimulate
the immunological cross-reactivity in
patients.
Pathogenesis
M antibody+Vascular C antibody+Cardiovascular
smooth muscle
connective tissue
Antigen antibody complex
Local deposition
alexin
platelet
activation of
coagulation
system
Neutrophil infiltration
Embolism,
bleeding
Release of lysosomal enzymes(Neutral, acid hydrolases, elastase,
collagenase and so on
Blood vessel, tissue injury
Basic pathological changes
1. Exudative and degenerative phase
2. The proliferative phase (Granulomatous period)
3. Scar phase (healed phase\Fibrosis phase\Hardening
phase)
Exudative and degenerative phase
It is characterized by serofibrinous exudate, with deposits of
immune precipitate on collagen fibers that lead to fibrinoid
necrosis. About 1 months.
The proliferative phase (Granulomatous period)
Aschoff Body: pathognomonic for RF
Structure:
center: fibrinoid necrosis
around the center:Anitschkow cells , lymphocytes,
occasional plasma cells
Distribution:
Myocardial interstitial, subendocardial and subcutaneous
connective tissue. Epicardial, joints and blood vessels is
rare.
Anitschkow cells:
These distinctive cells have abundant cytoplasm
and central round-to-ovoid nuclei in which the
chromatin is disposed in a central, slender, wavy
ribbon (hence the designation "caterpillar cells“-cross section named Owl 's eye cells).
Some of the larger macrophages become
multinucleated to form Aschoff cells(inflammatory
giant cells).
The myocardial interstitium has a circumscribed collection of
mononuclear inflammatory cells, including some large histiocytes
with prominent nucleoli and a prominent binuclear histiocyte, and
central necrosis
Aschoff cells
Owl 's eye cells
Scar phase
Emergence of fibroblasts and collagen
production, formation of small spindle scar, 2-3
months or so.
The above three stages repeated attacks, the
old and new lesions coexist.
The whole course about 4-6 months.
RF involves various organs
Rheumatic heart disease
Rheumatic arthritis
Rheumatic arteritis
Rheumatic disease of skin
Rheumatic disease of brain
Rheumatic heart disease
Divided into rheumatic endocarditis,
rheumatic myocarditis and rheumatic
pericarditis, often for rheumatic
pancarditis.
60% to 80% children associated with
pancarditis。
Key morphologic
features of acute
rheumatic heart
disease.
rheumatic endocarditis
The most important lesions caused by rheumatism,
valvular deformity and dysfunction
Lesions were most often involved: mitral valve
Secondly: both mitral and aortic valve
Pathological changes:
early stage: serous endocarditis , valve swelling,translucent
Microscopically: valve become loose due to serous
exudate , accompanied by macrophages entering and
fibrinoid necrosis of collagen fiber.
Concomitant involvement of the endocardium and the leftsided valves by inflammatory foci typically results the
small (diameter 1- to 2-mm) vegetations .
Vegetations: White thrombus consist of platelet and
cellulose.
Acute rheumatic endocarditis: small (diameter 1- to 2-mm)
vegetations along the mitral valve margin, insufficient to cause
valvular deformation.
Small vegetations (verruca) are visible along the line
of closure of the mitral valve leaflet (arrows).
Advanced: vegetations organization, recurrent organization cause
chronic heart valve disease ( valvular stenosis and / or valvular
insufficiency )
Mitral stenosis with diffuse fibrous thickening and distortion of
the valve leaflets, commissural fusion (arrows), and thickening
and shortening of the chordae tendineae.
rheumatic myocarditis
location:Myocardial interstitial
connective tissue
pathological changes: Rheumatic Granuloma
Perivascular Rheumatic Granuloma formation. Children often
occurred to diffuse myocardial interstitial edema, inflammatory
cell infiltration, congestive heart failure. Late effects myocardial
contractile force.
rheumatic pericarditis
A serous or serous fibrinous inflammation. Can
form a pericardial effusion, trichocardia
and constrictive pericarditis.
Serous pericarditis
Fibrinous pericarditis
Can lead to heart sound
far, around the heart
boundary expanding,
serious cardiac X-ray
showed a flask
pericardial
effusion
Adhesive pericardit is in
cardiac surface of patients.
From the epicardial surface
to the pericardial sac visible
fibrinous exudate, which is
typical for a fibrinous
pericarditis.
trichocardia
Can lead to
precordial pain,
pericardial friction
sound, serious
cause constrictive
pericarditis,
influence on
cardiac function.
Rheumatoid arthritis
predilection age: Adults
predilection site: involving the large joints, most
commonly in the knee and ankle joint, followed by
the shoulder, wrist, elbow and other joints
Lesion characteristics: migratory polyarthritis.
Local serous exudate, appear red, swelling, heat,
pain and dysfunction. As the heals , serous exudate is
absorbed, generally no sequela.
Microscopic lesions mainly for serous inflammation.
lick the knee but bite the heart.
rheumatic arteritis
Involving the coronary arteries, renal artery, brain
artery etc, small arteries see more.
Vascular wall connective tissue myxoid degeneration
and fibrinoid necrosis. There can see Rheumatic
Granuloma, and later wall narrow even block, with
thrombosis.
Rheumatoid coronary artery inflammation.
Rheumatic disease of skin
Mainly in acute period
1 subcutaneous nodules ( hyperplasia ):
2 The annular erythema (exudative lesions) :
Appear on the extremities and the trunk skin.
1-2 days. Hyperemia, edema changes of the
superficial layer of dermis. (pathognomonic )
annular erythema
Rheumatic disease of brain
Mainly involving the cerebral cortex, basal
ganglia, thalamus and cerebellum cortex.
Lesions to rheumatic arteritis and
subcortical encephalitis.
In 5-12 years old children, girls see more.
Infective endocarditis
(IE)
Infective endocarditis, one of the most serious of all
infections, is characterized by colonization or
invasion of the heart valves or the mural
endocardium by a microbe, leading to the formation
of bulky, friable vegetations composed of thrombotic
debris and organisms, often associated with
destruction of the underlying cardiac tissues.
Traditionally, IE has been classified on
clinical grounds into acute and subacute forms.
1. Acute IE
2. Subacute IE
1Acute IE :The strong pathogenic pyogenic bacteria
(carbuncle, puerperal fever, osteomyelitis )--resistance down---bacteria into the blood---sepsis--normal endocardium ---invasion of mitral valve,
aortic valve---acute septic endocarditis---bacterial
vegetations
2Subacute IE: Streptococcus viridans (localized
infection focus in vivo or iatrogenic infection)---bacteria into the blood---the mitral valve or/and
aortic valve with original lesions ( 80%,
congenital heart disease, RHD or valve repair)-Subacute IE--bacterial vegetations
Pathological change
In both the subacute and acute forms of the disease,
friable, bulky, and potentially destructive vegetations
containing fibrin, inflammatory cells, and bacteria or
other organisms are present on the heart valves.
vegetations ( microscopic ): cellulose + platelet +inflammatory
cell + bacteria group
In the aortic opening a larger, irregular red vegetations, this
mostly by Staphylococcus aureus infection.
Acute IE :Caused the distant organ septic infarction and abscess.
Valve rupture, perforation, rupture of chordae tendineae, leading
to chronic valvular heart disease. 50% died in days or weeks.
Subacute IE
End and complications:
1.Fever: it is the most consistent sign of IE. However, with
subacute disease, particularly in the elderly, fever
may be slight or absent, and the only manifestations
are sometimes nonspecific fatigue, loss of weight, and
a flulike syndrome. In contrast, acute endocarditis
has a stormy onset with rapidly developing fever,
chills, weakness, and lassitude.
2.Arterial embolization ( 20%-40% ): embolism of
brain ,heart, kidney, spleen, mesenteric, limbs and
pulmonary.
3.Chronic valvular disease
4.non-specific symptoms:
Splenomegaly (15%-50% )
Anemia
Clubbing finger / toe
5. Peripheral symptoms
Peripheral symptoms: Micro vasculitis or micro
thrombus
Roth spots
splinter or subungual
hemorrhages
Peripheral symptoms
Osler nodes
Janeway lesions
splinter or subungual Hemorrhages:petechiae, red, linear, or
flame-shaped streaks in the nail bed of the digits
Osler nodes :
retinal hemorrhages
Janeway lesions: are small erythematous or hemorrhagic,
macular, nontender lesions on the palms and soles and are the
consequence of septic embolic events.
Osler nodes: are small, tender subcutaneous nodules that
develop in the pulp of the digits or occasionally more
proximally in the fingers and persist for hours to several days.
杵状指/趾
bacterial
virulence
valve
Subacute IE
Acute IE
weak
strong
Have lesions
normal
Dry, crisp
A larger, soft
vegetation Bacteria are less, little
or no necrosis
final result
Bacteria
into the
blood
embolism
the vast majority of
people heal
ichorrhemia
Many bacteria,
much necrosis
50% died in days or
weeks.
Sepsis
Non-infectious
infarction
Multiple embolic
microabscesses
Etiology
rheumatic
endocarditis
immunologically
mediated
Subacute IE
bacterial infection
grossly
White, small, compact
vegetations
gray red, large, loose
vegetations, fall off
easily
microscopically
white thrombus
White thrombus with
necrosis, colony etc.
clinical feature
Valvular Disease
Valvular heart disease,
thromboembolism,
infarction, Septicemia
connection
SIE often occurs on
the basis of RE