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Chapter 2: Rheumatic fever and valve disease 41

Lancefield group A (Streptococcus pyogenes). Risk fac- centre over the trunk and limbs, which appear and
torsforstreptococcalinfectionincludepovertyandover- disappear over a matter of hours.
crowded conditions, the reduction of which, together Subcutaneous painless nodules may be palpated over
with the increased use of antibiotics, may well explain theextensorsurfaces,tendons,jointsandbonypromi-
the decline in developed countries. nences.
Minor manifestations:pyrexia, raised ESR/CRP, arth-
ralgia, previous rheumatic fever, long PR interval on
Pathophysiology
ECG and a leucocytosis. Non-specific symptoms include
It appears that antistreptococcal antibodies crossre-
malaise and loss of appetite.
act with antigens in connective tissues, particularly of
Evidenceofaprecedingstreptococcalinfectionsuchas
endothelial-lined tissues such as blood vessels, endo-
positive throat culture, elevated antistreptolysin O titre
cardium, pericardium and synovial membranes. All
or other streptococcal antibodies is suggestive.
three layers of the heart may be affected (pancarditis);
the characteristic lesion is the Aschoff’s nodule (see in
section Microscopy below). Macroscopy
Pericarditis: Nodules are seen within the pericardium Fibrinous vegetations form on the edges of the valve

associated with an inflammatory pericardial effusion. leaflets with associated oedema. Valve leaflets may fuse
Myocarditis:Nodulesdevelopwithinthemyocardium and scar, particularly affecting the mitral and aortic

associated with inflammation. This may result in de- valves.
creased myocardial function and left ventricular fail-
ure.
Microscopy
Endocarditis: Nodules may form anywhere on the

Aschoff’s nodules are granulomatous lesions composed
endocardium, but tend to cause more damage and
of a necrotic core of degenerated collagen surrounded
erosion when they occur within the heart valves as
initially by macrophages and lymphocytes. Over time
vegetations. These may result in an acute disturbance
thesecellsarereplacedbyhistiocytes,whichmaybemult-
of valve function.
inucleated. Nodules heal by scarring.
Recurrent attacks may occur over many years.
Complications
Clinical features
More than 50% of patients with acute rheumatic cardi-
There may be a history of pharyngitis in up to 50% of
tis will develop chronic rheumatic valve disease 10–20
patients. The diagnosis is made on two or more major
years later, particularly mitral and aortic stenosis. These
manifestations or one major plus two or more minor
may be complicated by atrial fibrillation, heart failure,
manifestations (Duckett Jones criteria).
infective endocarditis and mural thrombus formation.
Major manifestations may be remembered as PACES:
Pancarditis presents with new or changed cardiac

murmurs (due to endocarditis) and the ECG changes Investigations
of myocarditis and pericarditis. A pericardial friction Cultures of blood and tissues are sterile by the time
rubmay be audible due to pericarditis. rheumatic fever manifests, but throat swabs may be
Arthritis affecting multiple large joints that ranges in positive and there may be serological evidence (raised

severity from mild aches to severe non-destructive antistreptolysin O titre or other antistreptococcal an-
arthritis, which may occur sequentially in different tibodies).
joints (flitting arthritis). Non-specific indicators of inflammation, such as a
Chorea (Sydenham’s chorea) is characterised by jerky raised ESR and leucocytosis.

non-repetitive movements associated with reduced ECG shows prolonged PR interval and non-specific
muscle tone. Postpuberty this manifestation is con- Twavechanges. Pericarditis may initially result in
fined to females. widespreadSTelevation,concaveupwards.Afterafew
Erythema marginatum is an erythematous rash com- days ST returns to the isoelectric point and there is T

posed of red, well-circumscribed lesions with a pale wave inversion.