Acute Rheumatic Fever: Treatment with Aspirin
This 21-year-old patient presenting with knee pain (arthritis), mild fever, and a new systolic murmur (carditis) 3 weeks after an upper respiratory tract infection has acute rheumatic fever, and the correct answer is D - acetylsalicylic acid (aspirin).
Clinical Reasoning
This presentation is classic for acute rheumatic fever (ARF):
- Timing: 3 weeks post-URTI is the typical latency period for post-streptococcal autoimmune response 1
- Major Jones Criteria present: Arthritis (knee pain) and carditis (new systolic murmur) 2
- Minor criteria: Fever 2
Primary Treatment Approach
Aspirin is the anti-inflammatory drug of choice for acute rheumatic fever, particularly when carditis is present 3, 4:
- Dosing: High-dose aspirin therapy (typically 80-100 mg/kg/day in divided doses for children/young adults, not exceeding 6-8 grams/day) 3
- Response: Expect prompt and dramatic improvement within 24-48 hours 4
- Duration: Continue until acute phase reactants normalize, then taper gradually over 2-4 weeks 3
The evidence strongly supports aspirin over other options:
- Adults with ARF show "prompt and dramatic" response to high-dose aspirin therapy 4
- Aspirin has been the standard treatment for decades in patients with carditis 3
- Paracetamol (acetaminophen) lacks anti-inflammatory properties needed for ARF 5
- Corticosteroids are reserved for severe carditis with heart failure, not first-line 2
Concurrent Essential Management
Antibiotic therapy must be initiated immediately 6, 7:
- Give a full therapeutic course of penicillin to eradicate residual group A Streptococcus, even if throat culture is negative 6, 7
- Start long-term secondary prophylaxis immediately after acute treatment 6
Secondary prophylaxis regimen 6, 7:
- First-line: Benzathine penicillin G 1.2 million units IM every 4 weeks 6, 7
- Duration: For this patient with carditis, continue for 10 years after the last attack OR until age 40, whichever is longer 6, 7
Critical Pitfalls to Avoid
- Do not use corticosteroids as first-line therapy: They are reserved for severe carditis with congestive heart failure, not for uncomplicated cases with mild carditis 2
- Do not substitute acetaminophen for aspirin: Acetaminophen lacks the anti-inflammatory properties essential for treating ARF 5
- Do not delay antibiotic prophylaxis: Start immediately after diagnosis to prevent recurrence, which carries higher risk of severe cardiac damage 6
- Do not assume valve replacement eliminates prophylaxis need: If this patient eventually needs valve surgery, continue secondary prophylaxis 7
Monitoring Requirements
- Obtain baseline echocardiogram at least 72 hours after acute episode to assess valvular involvement 8
- Monitor ESR/CRP to guide duration of aspirin therapy 8
- Watch for aspirin toxicity (tinnitus, hearing changes) and adjust dose accordingly 3
- Annual follow-up with history, physical exam, chest X-ray, and ECG for patients with confirmed carditis 8
The evidence is unequivocal: aspirin is the correct answer for this clinical scenario, combined with immediate penicillin therapy and long-term prophylaxis.