Acute rheumatic fever

5.6 Acute rheumatic fever



Sarah Dalton




Essentials



1 Acute rheumatic fever (ARF) is a disease of connective tissue inflammation that may follow 2 to 4 weeks after a Group A streptococcal throat infection.

2 Diagnosis is based on the presence of carditis, arthritis, skin and neuropsychiatric sequelae.

3 The major complication of recurrent disease is progressive destruction of cardiac valves leading to rheumatic heart disease.

4 Treatment is comprised of eliminating streptococci, controlling joint pain and managing carditis, heart failure and chorea.

5 Antibiotic prophylaxis to prevent further attacks of ARF and episodes of infective endocarditis is mandatory.


Introduction


Acute rheumatic fever (ARF) is an acute inflammatory disease that may follow group A β-haemolytic streptococcal infection. It primarily affects connective tissue, causing carditis, arthritis and chorea and may follow a remitting and relapsing course for several years after the primary episode. Long-term complications of recurrent disease include progressive cardiac damage, which is associated with significant morbidity and mortality in the adult population.



Epidemiology


Rheumatic heart disease (RHD) is steadily decreasing in the developed world in association with improved standards of living and the availability of penicillin. Amongst developing countries prevalence is variable, with one of the highest prevalences worldwide found in the indigenous Australian communities. A family history of ARF is common, reflecting genetic predisposition as well as environmental influences.



Pathophysiology


The exact pathogenesis of ARF remains unclear. It is postulated that certain virulent strains of Gram-positive Group A β-haemolytic streptococci (Streptococcus pyogenes) invade the pharynx, leading to the production of anti-streptococcal antibodies, which cross-react with host connective tissue.



History


Acute rheumatic fever usually presents in school-age children but may present at any age. A history of pharyngitis several weeks previously is found in 70% of older children, but younger children are less likely to recall a sore throat. Typically, ARF presents with up to a week of high fevers, followed by several weeks of milder temperatures and the appearance of a rash (erythema marginatum). Specific symptoms include migratory joint pain, chorea, and neuropsychiatric manifestations such as abrupt personality change or poor attention span. There may be symptoms of congestive heart failure or non-specific symptoms such as weight loss, fatigue, pallor, headache and abdominal pain.



Examination


The diagnosis of ARF relies upon the identification of specific clinical features. The National Heart Foundation of Australia has developed diagnostic criteria which depend on the stratification of patient risk (Table 5.6.1). High-risk groups are those who live in communities with high rates of ARF or RHD such as Aboriginal and Torres Strait Islanders.

















Table 5.6.1 Diagnostic criteria for acute rheumatic fever
High-risk group All other individuals
Major manifestations
Carditis (including subclinical echocardiograph evidence)
Polyarthritis, aseptic monoarthritis, or polyarthralgia
Erythema marginatum
Subcutaneous nodules
Chorea		 Carditis (excluding subclinical echocardiograph evidence)
Polyarthritis
Erythema marginatum
Subcutaneous nodules
Chorea
Minor manifestations
Fever (documented >38°C)
ESR >30 mm hr–1 or CRP >30 mg L–1
Prolonged PR interval on ECG		 Fever (documented >38°C)
ESR >30 mm hr–1 or CRP
>30 mg L–1
Prolonged PR interval on ECG
Polyarthralgia or aseptic monoarthritis

Amended from National Heart Foundation of Australia; Diagnosis and management of acute rheumatic fever and rheumatic heart disease in Australia – an evidence-based review. 2006.


An initial episode of ARF may be diagnosed where two major or one major and two minor manifestations are present. The same criteria may be used to diagnose a recurrent episode, which otherwise requires the presence of three minor manifestations. All diagnoses require evidence of preceding Group A streptococcal (GAS) infection.



Carditis


A pancarditis, manifested as endocarditis, myocarditis or pericarditis, occurs in nearly 50% of cases of ARF. Clinical diagnosis begins with the identification of a new or changing murmur that must be distinguished from an innocent murmur in a febrile child. The mitral valve is most commonly affected, followed by the aortic valve. Myocarditis may be associated with a disproportionate sinus tachycardia or rhythm disturbance, such as first degree heart block. Signs of pericarditis or congestive heart failure may be present. Recurrent rheumatic fever leads to progressive valve damage and RHD.

Related posts:

Syncope Default ThumbnailCSF shunt complications Default ThumbnailThyroid emergencies CNS infections: meningitis and encephalitis Default ThumbnailGeneral approach to poisoning Specific poisons

Stay updated, free articles. Join our Telegram channel
Tags:
Sep 7, 2016 | Posted by in EMERGENCY MEDICINE | Comments Off on Acute rheumatic fever

Full access? Get Clinical Tree
Get Clinical Tree app for offline access