Rheumatic Fever (ARF)

Acute rheumatic fever (ARF) is an inflammation of the heart, skin, joints and/or brain which develops after infection with Group A streptococci, such as "strep" throat, or scarlet fever. Although the incidence of ARF has declined in Europe and North America over the past 4 to 6 decades, the disease remains one of the most important causes of cardiovascular morbidity and mortality in the developing countries that are home to the majority of the world's population. There is a 2-3 weeks delay between the strep infection and the development of ARF. Less than 3% of those with untreated strep infection may develop ARF. Most of the affected patients are between six and fifteen years of age.

Pathology

Group A streptococcal (GAS) infection of the pharynx is usually the precipitating cause of rheumatic fever. During epidemics over a half a century ago, as many as 3% of untreated acute streptococcal sore throats were followed by rheumatic fever; in endemic infections, the incidence of rheumatic fever is substantially less. Appropriate antibiotic treatment of streptococcal pharyngitis prevents acute rheumatic fever in most cases. Unfortunately, at least one third of episodes of acute rheumatic fever result from inapparent streptococcal infections. In addition, some symptomatic patients may not seek appropriate medical care. Among the most widely accepted concepts in support of an autoimmune hypothesis involving the GAS was the observation by Stollerman. He noted a correlation between outbreaks of GAS upper respiratory tract infections associated with a relatively limited number of M-protein types which were followed by outbreaks of rheumatic fever. Subsequent reports demonstrated that only a limited number of specific M-types (M-5, M-6, M-18) were isolated during rheumatic fever outbreaks. These findings supported the concept of antigenic mimicry. In ARF, antibodies against the M antigen found in the streptococcal cell wall cross react with cardiac myosin causing carditis.

 

Features suggestive of GAS infection

Features suggestive of viral infection

Sudden onset sore throat with painful swallowing

Conjunctivitis

Fever

Coryza

Scarlet fever rash

Hoarseness

Headache, nausea and vomiting

Cough

Tonsillar exudates with soft palate petechiae

Diarrhea

Tender enlarged anterior cervical nodes

Characteristic exanthems

Patient age 5-15 years with a h/o exposure

Characteristic enanthems

Prevention of rheumatic fever requires adequate therapy for GAS pharyngitis. In selecting a regimen for the treatment of GAS pharyngitis, physicians should consider various factors, including bacteriologic and clinical efficacy, ease of adherence to the recommended regimen (frequency of daily administration, duration of therapy, and palatability), cost, spectrum of activity of the selected agent, and the potential side effects.

Agent

Dose

Duration

Penicillins

 

 

 

 

Penicillin V

< 27 kg: 250 mg BID/TID

 

 

>27 kg: 500 mg BID/TID

10 days

 

 

10 days

Amoxicillin

50 mg/kg daily

10 days

Benzathine Penicillin G

<27 kg: 600,000 U IM

 

 

>27 kg: 1.2 million U IM

Once

 

 

Once

Penicillin allergic

 

 

 

 

Cephalexin/Cefadroxil

Variable

10 days

Azithromycin

12 mg/kg (max 500 mg) daily

5 days

Clindamycin

20 mg/kg divided in 3 doses (max 1.8 g/day)

10 days

Clinical presentation

Signs and symptoms of rheumatic fever include fever, migratory arthritis in large joints, abdominal pain, erythema marginatum (a ring-shaped rash located on trunk and upper parts of arms and legs), Sydenham chorea, subcutaneous nodules, epistaxis, shortness of breath and chest pain.

Making the diagnosis

According to Jones Criteria, there must be evidence of previous streptococcal infection.

Any of the following may serve as evidence of GAS infection:

  1. Increased or rising ASO titer or other streptococcal antibody such as Anti DNAase B
  2. A positive throat Cx for GAS
  3. A positive rapid test for GAS

Major Criteria:

Minor Criteria:

 For ARF diagnosis, 2 major OR one major + two minor criteria are needed.

Management Principles:

General treatment of the acute episode:

Cardiac management:

Prevention

Patients with a documented history of ARF should receive antibiotic prophylaxis until the age of 21 or for a minimum of five years if there is no cardiac involvement. Patients with valvular abnormalities should receive lifetime prophylaxis.   Prophylaxis consists of monthly injections of benzathine penicillin; alternatively, twice daily oral penicillin V may be used. Oral sulfadiazine may be used for patients with penicillin allergy, but it is not as effective as penicillin.

Prevention of Rheumatic Fever and Diagnosis and Treatment of Acute Streptococcal Pharyngitis: A Scientific Statement From the American Heart Association Rheumatic Fever, Endocarditis, and Kawasaki Disease Committee of the Council on Cardiovascular Disease in the Young, the Interdisciplinary Council on Functional Genomics and Translational Biology, and the Interdisciplinary Council on Quality of Care and Outcomes Research: Endorsed by the American Academy of Pediatrics, 2004.

Bach DS. Revised Jones Criteria for Acute Rheumatic Fever ACC, May 2015

 

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