What is the most appropriate initial management for a 21-year-old patient presenting with knee pain, mild fever, and a systolic murmur three weeks after an upper respiratory tract infection (URTI)?

Acute Rheumatic Fever: Acetylsalicylic Acid is the Appropriate Treatment

This patient has acute rheumatic fever (ARF) following a streptococcal pharyngitis, and acetylsalicylic acid (aspirin) is the treatment of choice for the arthritis and fever, along with antibiotics to eradicate residual streptococcal infection. 1

Clinical Presentation Analysis

This 21-year-old presents with the classic triad of acute rheumatic fever:

• Polyarthritis (knee pain) occurring 3 weeks post-URTI 2
• Carditis (new systolic murmur) 1
• Fever 1

The 3-week interval between upper respiratory tract infection and current symptoms is the typical latency period for post-streptococcal sequelae, specifically acute rheumatic fever 2. The systolic murmur indicates mitral regurgitation from carditis, which can develop or become apparent during the acute phase of rheumatic fever 1.

Why Acetylsalicylic Acid (Option C)

Aspirin is the cornerstone anti-inflammatory treatment for acute rheumatic fever with arthritis. 1 In the documented case of an adult with rheumatic fever presenting with polyarthritis and carditis detected by new systolic murmur, initial treatment included anti-inflammatory therapy 1.

Treatment Rationale:

• High-dose aspirin effectively treats the polyarthritis and fever of acute rheumatic fever 1
• Aspirin provides superior anti-inflammatory effects compared to paracetamol for rheumatic inflammation 1
• The arthritis in ARF is typically dramatic and responds rapidly to salicylates 1

Why Not the Other Options

Paracetamol (Option B):

• While paracetamol is a pain reliever and fever reducer 3, it lacks the anti-inflammatory properties necessary to treat rheumatic fever
• Paracetamol only provides symptomatic relief without addressing the underlying inflammatory process 3
• The case report specifically notes that NSAID therapy (not simple antipyretics) was required 1

Corticosteroids (Option A):

• Corticosteroids are reserved for severe carditis with heart failure 1
• In the documented case, corticosteroids (prednisolone 40mg/day) were only escalated when carditis appeared and worsened despite initial anti-inflammatory treatment 1
• Initial presentation with mild fever and arthritis does not warrant immediate corticosteroid therapy 1
• Starting with aspirin allows assessment of disease severity before escalating to steroids 1

Critical Management Points

Immediate Actions Required:

• Start high-dose aspirin for anti-inflammatory effect 1
• Initiate antibiotic therapy (penicillin or alternative) to eradicate residual streptococcal infection 2
• Obtain echocardiography to assess degree of valvular involvement 1
• Check ASO titers to confirm recent streptococcal infection 1

Monitoring for Escalation:

• If the systolic murmur worsens or signs of heart failure develop, escalation to corticosteroids becomes necessary 1
• The case report demonstrates that when carditis progressed (detected by worsening systolic murmur), prednisolone dose was increased to 40mg/day with prompt improvement 1

Common Pitfall:

Do not dismiss a new systolic murmur in a young patient with recent URTI and arthritis. This triad mandates evaluation for acute rheumatic fever, as delayed recognition can lead to permanent valvular damage 1. The murmur may not be present initially but can appear during the acute phase, as documented in the case where it developed after hospital admission 1.