🩺 Acute Rheumatic Fever (ARF)

Description

Acute Rheumatic Fever (ARF) is an acute autoimmune process that develops following pharyngitis caused by Group A β-haemolytic Streptococcus infection.

Diagnosis is based on the Modified Jones Criteria (2015), which recognizes high-risk populations and includes echocardiography for detecting subclinical carditis.

Table 45: Modified 2015 Jones’ Criteria

Note:
ESR = Erythrocyte Sedimentation Rate; CRP = C-Reactive Protein.
All patients with ARF should have Echocardiography done even if there is no clinical suspicion of valvular involvement.

Diagnostic Requirements

• Two major manifestations plus evidence of preceding streptococcal infection,
  OR

• One major and two minor manifestations plus evidence of preceding streptococcal infection.

Investigations

• Full Blood Count/Differential Count (FBC/DC)

• Erythrocyte Sedimentation Rate (ESR) / C-Reactive Protein (CRP)

• Throat swab culture for Streptococcus

• Anti-Streptolysin O Titre (ASOT)

• Electrocardiogram (ECG)

• Echocardiography (ECHO)

• Chest X-ray (CXR)

Treatment

Antibiotic Therapy

• Benzathine penicillin IM injection: 600,000 IU – 1.2 million units stat
  OR

• Oral Phenoxymethylpenicillin: 10–12.5 mg/kg/dose twice daily for 10 days (maximum 500 mg every 6 hours).

• If penicillin hypersensitive: Oral first-generation cephalosporins for 10 days.

Symptomatic Treatment

• Bed rest

• Analgesia and anti-inflammatory agents for arthritis, pain, and fever

• Treat chorea (if severe)

• Manage heart failure as indicated (refer to CCF section)

 Management of Acute Rheumatic Fever (ARF)

Notes:

• Taper prednisolone by 20–25% per week.

• When symptoms improve, reduce aspirin to 25–30 mg/kg/day.

• Begin aspirin during the final week of steroid tapering.

Management of Sydenham’s Chorea

• Reduce physical and emotional stress.

• Use protective measures where needed.

• Administer Benzathine Penicillin IM stat to eradicate GAS, then continue every 28 days for secondary prophylaxis.

• Anti-inflammatory agents not indicated.

For severe chorea, use one of the following:

• Carbamazepine: 7–20 mg/kg/day (typically 7–10 mg/kg/day) in 3 divided doses orally until chorea is controlled for ≥2 weeks, then trial off.

• Valproic acid: 15–20 mg/kg/day (may increase to 30 mg/kg/day) in 3 divided doses orally until chorea is controlled for ≥2 weeks, then trial off.

• Alternative agents: Phenobarbitone, Haloperidol, or Chlorpromazine (if above not available).

Further Management Plan

• Register patient under ARF register (cardiac clinic).

• Issue Acute Rheumatic Fever prophylaxis card.

• Educate patient and family.

• Conduct dental examination.

• Establish long-term secondary prophylaxis.

Purpose of Secondary Prophylaxis

To prevent:

• Group A β-Haemolytic Streptococcal (GAS) pharyngitis.

• Recurrence of ARF.

• Development or progression of Rheumatic Heart Disease (RHD).

• Severe RHD-related complications or death.

Table 47: Antibiotic Regimens for Secondary Prophylaxis

Note:

• Duration of prophylaxis: minimum 10 years after the last episode or until age 21 years (whichever is longer).

• For Rheumatic Heart Disease (RHD): lifelong prophylaxis is recommended.