Page 286 - Concise Pathology for Exam Preparation ( PDFDrive )

11 Disorders of the Heart 271

2. Polyarthritis
(a) Arthritis is the most common major manifestation of rheumatic fever (present in
nearly 75% of cases).
(b) Classical presentation is acute migratory or fleeting polyarthritis (most commonly
of large joints of the extremities). As pain and swelling subside in one joint, others
tend to get involved.
(c) Involvement of hips, small joints of hands and feet, spine, sternoclavicular and
temporomandibular joints is rare.
(d) Affected joints show signs of inflammation with or without effusion.
(e) Over a period of time, involved joints heal without any residual deformity.
3. Carditis
(a) Features of carditis develop early (within 3 weeks of onset) and occur in 40–50%
of cases.
(b) May be asymptomatic and picked up on echocardiography only.
Manifestations of carditis
• Myocarditis
- Tachycardia, disproportionate to fever and persisting during sleep
- Arrhythmias of which prolongation of PR interval is the most common
- Features of congestive heart failure and cardiomegaly
• Endocarditis
- Apical systolic murmur of mitral regurgitation
- Apical mid-diastolic murmur (Carey Coombs murmur) due to nodules on the
mitral valve leaflets
- Basal early diastolic murmur of aortic regurgitation
• Pericarditis
- Pericardial pain
- Pericardial friction rub
- Pericardial effusion (uncommon and always small)
Diagnosis of carditis requires the presence of one or more of the following:
• Appearance of, or change in the character of organic murmurs
• Cardiomegaly
• Pericarditis or pericardial effusion
• Congestive heart failure
4. Subcutaneous nodules
(a) Associated with severe carditis and tend to occur several weeks after its onset (de-
layed manifestation)
(b) Manifest as small, painless nodules over extensor surfaces and bony prominences
5. Erythema marginatum
(a) Occurs in nearly 10% cases of acute rheumatic fever
(b) Characterized by erythematous macules with a clear centre and serpiginous mar-
gins, most commonly seen on the trunk and proximal parts of extremities
6. Chorea (Sydenham chorea; chorea minor; Saint Vitus Dance)
(a) Chorea usually appears following a long latent period (up to 6 months) after the
initial streptococcal infection
(b) Purposeless, involuntary movements associated with muscle weakness, emotional
instability, tics and psychotic features characterize chorea

Chronic Rheumatic Fever
The average duration of an untreated attack of acute rheumatic fever is approximately
3 months. Chronic rheumatic fever is defined as disease persisting for longer than
6 months and may be a cause of persisting congestive heart failure.

Laboratory investigations for Acute Rheumatic Fever:

1. Isolation of group A streptococci: Positive throat swab cultures for group A streptococci
2. Streptococcal antibody tests (serologic tests):
(a) These tests confirm a recent streptococcal infection.

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