Question

What are the diagnostic criteria for rheumatic fever?

Hint:

The Jones criteria are crucial for diagnosing rheumatic fever and distinguishing it from other causes of similar symptoms.

Answer 1

Step 1: Introduction to Diagnostic Criteria.
The diagnosis of rheumatic fever is based on the Jones Criteria, which includes major and minor criteria. These criteria help confirm the diagnosis when there is a history of a recent streptococcal infection.
Step 2: Major Criteria (Required for Diagnosis).
The major criteria are indicative of systemic involvement and include:
(1) Carditis: Inflammation of the heart, often affecting the mitral valve, leading to murmurs, heart failure, or pericarditis.
(2) Polyarthritis: Migratory inflammation of large joints (e.g., knees, elbows, wrists). It is typically transient and moves from one joint to another.
(3) Chorea (Sydenham’s chore: A neurological manifestation characterized by involuntary, jerky movements.
(4) Erythema Marginatum: A characteristic, non-itchy, raised, red rash with a well-defined edge, usually found on the trunk and limbs.
(5) Subcutaneous Nodules: Painless, firm nodules that appear over joints or tendons.
Step 3: Minor Criteria (Supportive for Diagnosis).
Minor criteria include evidence of previous streptococcal infection and nonspecific findings:
(1) Fever: Elevated body temperature (above 38°.
(2) Arthralgia: Joint pain without evidence of inflammation.
(3) Elevated Acute Phase Reactants: Elevated ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein).
(4) Prolonged PR Interval: Seen on electrocardiogram (ECG), indicating heart conduction disturbances.
Step 4: Diagnosis of Rheumatic Fever.
- A diagnosis of rheumatic fever is made if there is evidence of a recent streptococcal throat infection (positive throat culture or rapid antigen test) along with two major criteria or one major and two minor criteria.