Acute Rheumatic Fever¶

Learning Objectives¶

Core Knowledge & Clinical Reasoning¶

[ ] Apply 2015 Revised Jones Criteria correctly including major and minor criteria
[ ] Differentiate diagnostic criteria for low-risk vs high-risk/moderate-risk populations
[ ] Recognize subclinical carditis on echocardiography (pathologic MR/AR without auscultatory findings)
[ ] Evaluate evidence of preceding streptococcal infection (ASO, anti-DNase B, culture, rapid test)

Management¶

[ ] Formulate acute treatment plan including anti-inflammatory therapy and antibiotics
[ ] Prescribe appropriate secondary prophylaxis regimen and duration based on carditis status

Communication & Counseling¶

[ ] Counsel families on importance of adherence to secondary prophylaxis (penicillin injections)
[ ] Discuss long-term prognosis and risk of recurrence without prophylaxis

Systems-Based Practice¶

[ ] Coordinate transition of care for patients moving between healthcare settings
[ ] Ensure appropriate echo surveillance for patients with carditis

Key Guidelines¶

2015 AHA Revised Jones Criteria Circulation. 2015;131:1806-1818

2024 WHO Guideline on Prevention and Diagnosis of RF/RHD

Epidemiology¶

Follows Group A Streptococcal (GAS) pharyngitis
Peak age: 5-15 years
Rare in developed countries; common globally
~470,000 new cases/year worldwide

Population-Based Risk Stratification¶

Population	Definition
Low-risk	ARF incidence ≤2 per 100,000 school-age children/year
Moderate/High-risk	ARF incidence >2 per 100,000/year

Most of US = Low-risk Indigenous populations, developing countries = High-risk

2015 Revised Jones Criteria¶

Initial ARF Diagnosis¶

Requires: - Evidence of preceding GAS infection, PLUS - 2 major criteria, OR - 1 major + 2 minor criteria

Recurrent ARF (Prior RHD)¶

Requires: - Evidence of preceding GAS infection, PLUS - 2 major criteria, OR - 1 major + 2 minor criteria, OR - 3 minor criteria

Major Criteria¶

Criterion	Low-Risk Population	High-Risk Population
Carditis	Clinical OR subclinical (echo)	Clinical OR subclinical (echo)
Arthritis	Polyarthritis only	Polyarthritis OR monoarthritis
Chorea	Yes	Yes
Erythema marginatum	Yes	Yes
Subcutaneous nodules	Yes	Yes

Minor Criteria¶

Criterion	Low-Risk Population	High-Risk Population
Arthralgia	Polyarthralgia	Polyarthralgia OR monoarthralgia
Fever	≥38.5°C	≥38°C
ESR	≥60 mm/hr	≥30 mm/hr
CRP	≥3.0 mg/dL	≥3.0 mg/dL
Prolonged PR interval	Age-appropriate	Age-appropriate

KEY UPDATE: Subclinical Carditis¶

Echo findings NOW count as MAJOR criterion (carditis):

Must echo ALL suspected ARF cases!

Pathologic Mitral Regurgitation¶

Jet seen in ≥2 views
Jet length ≥2 cm in at least 1 view
Peak velocity >3 m/s
Pansystolic jet in at least 1 envelope

Pathologic Aortic Regurgitation¶

Jet seen in ≥2 views
Jet length ≥1 cm in at least 1 view
Peak velocity >3 m/s
Pandiastolic jet in at least 1 envelope

Evidence of GAS Infection¶

At least ONE required: - Positive throat culture - Positive rapid antigen test - Elevated/rising streptococcal antibody titers (ASO, anti-DNase B) - Recent scarlet fever

Clinical Manifestations¶

Carditis (50-70%)¶

Valvulitis (MR most common, then AR)
Myocarditis
Pericarditis
CHF in severe cases

Arthritis (75%)¶

Migratory polyarthritis (large joints)
Exquisitely painful
Resolves without sequelae
Dramatic response to aspirin/NSAIDs

Sydenham Chorea (10-30%)¶

May appear months after infection
May be sole manifestation
Emotional lability, muscle weakness
Resolves in months but may recur

Erythema Marginatum (<5%)¶

Evanescent, pink, non-pruritic
Trunk and proximal extremities
Central clearing

Subcutaneous Nodules (<5%)¶

Firm, painless
Over bony prominences
Associated with severe carditis

Treatment¶

Acute Episode¶

Aspirin: High-dose for arthritis/fever
Corticosteroids: Severe carditis (controversial)
Penicillin: Eradicate GAS
Bed rest: During acute inflammation

Secondary Prophylaxis¶

See Topic 30: Rheumatic Heart Disease

Board Pearls¶

Pearl: Subclinical carditis on echo NOW counts as MAJOR criterion

Echo ALL suspected ARF cases; changed diagnostic sensitivity significantly

Pearl: High-risk populations: Monoarthritis can be major criterion

More sensitive criteria for endemic areas

Pearl: Polyarthralgia is minor in LOW-risk but may be major in HIGH-risk

Know the population-based differences

Self-Assessment¶

Q1: A 10-year-old in the US presents with fever (39°C), migratory arthritis affecting knees and ankles, and elevated ASO titers. Echo shows pathologic MR meeting criteria. How many major and minor criteria are present?

Answer

**Answer**: 2 major criteria (polyarthritis + carditis); diagnosis confirmed **Rationale**: In low-risk populations (US), polyarthritis is a major criterion, and subclinical/clinical carditis is a major criterion. With 2 major criteria + evidence of GAS infection (elevated ASO), the diagnosis of ARF is confirmed.

Q2: A 7-year-old in an endemic area presents with fever (38.2°C), monoarthritis of the right knee, elevated CRP, and prolonged PR interval. ASO is elevated. Can ARF be diagnosed?