In this post I link to and excerpt from the outstanding podcast and transcript for Acute Rheumatic Fever by Mahabba Smoka Aug 29, 2018 by PedsCases.
What follows are excerpts from the transcript:
Developed by Mahabba Smoka and Dr. Dax Rumsey for PedsCases.com. August 29, 2018
This podcast covers acute rheumatic fever, including presentation, diagnosis, investigations and management. This podcast was developed by Mahabba Smoka, a medical student at the University of Alberta and Dr. Dax Rumsey, a Pediatric Rheumatologist at the University of Alberta and Stollery Children’s Hospital in Edmonton, Canada.
The Case
Let’s start off with a case! You are working at a general pediatric community clinic and a 7-year-old girl presents with her father. The patient’s father reports that he has noticed his daughter fidgeting constantly and making jerky movements with her arms and legs.
She also has a low-grade fever and has been experiencing aches in her knees and ankles that seem to come and go.
On history, you learn that the patient is a healthy girl with an unremarkable medical history, although she did complain of a sore throat about a month ago.
You perform a physical exam. On inspection, you see an erythematous rash on her abdomen. On auscultation, you hear a holosystolic murmur in the area of the apex of the heart which radiates to the axilla.
Based on the history and physical exam, you suspect that this patient has ARF. How are you going to confirm her diagnosis and manage her accordingly?
Definition and Criteria for Diagnosis
ARF is a childhood inflammatory disease that can affect multiple organ systems and is triggered by a preceding infection of the tonsils and/or pharynx with Group A βHemolytic Streptococcus (GAS). There is a 2-3 week latency period between the initial infection with GAS and the resulting clinical picture of ARF. The diagnosis of ARF is not based on a single definitive test but on a combination of clinical and laboratory findings that satisfy the classification criteria known as the Jones Criteria.
A patient is said to have ARF if there is the presence of two major manifestations or one major and two minorvmanifestations AND supporting evidence of an antecedent GAS infection.
It should be noted that these are classification criteria, not diagnostic criteria, so clinical judgement is paramount.
1. The major manifestations of the Jones criteria can be remembered by using the mnemonic JONES = J-O-N-E-S and imagining a heart shape in place of the O!
- J = migratory polyarthritis (J stands for joints!)
- O = carditis (O shaped like a heart!)
- N = subcutaneous nodules (N stands for Nodules!)
- E = erythema marginatum (rash) (E stands for Erythema!)
- S = Sydenham chorea (S stands for Sydenham!)
2. The minor manifestations of the Jones criteria include:
- fever
- arthralgia,
- elevated acute phase reactants (ESR/CRP)*,
- prolonged PR interval on ECG.
*ESR ≥30 mm/h and/or CRP ≥3.0 mg/dL from Acute Rheumatic Fever Workup from emedicine.medscape.com
3. Supporting evidence of an antecedent GAS infection can be obtained with elevated streptococcal antibody titres (anti-streptolysin O or anti-deoxyribonuclease B) or a positive throat swab.
4. Joint (arthritis or arthralgias) and cardiac (carditis or prolonged PR interval) manifestations can only be counted once as either a major or minor criterion but not both.
Epidemiology and Etiology
As mentioned previously, ARF is predominantly a childhood disease. It typically occurs in children between the ages of 6-15 years at a 1:1 ratio between males and females. Children in developing countries have the highest incidence, while children in Western Europe and North America have seen a decline in incidence as a result of less crowding in homes/schools and increasing access to healthcare. . . . Ethnically, ARF is more common among African American and Hispanic children than Caucasian children.
ARF is a complication of tonsillopharyngitis caused only by the GAS bacterial pathogen. It is caused by molecular mimicry. Antibodies against GAS cross-react with antigens on the organs (e.g. heart) of susceptible hosts.
Only 2% of individuals with GAS pharyngitis develop ARF based on a combination of factors that include a susceptible host, a virulent strain of GAS, and the site of infection.
ARF can usually be prevented with appropriate identification and treatment of tonsillopharyngitis within 10 days after onset of symptoms (i.e. sore throat).
Clinical Presentation and Differential Diagnosis
The onset of ARF occurs 2-3 weeks following an initial tonsillopharyngeal infection with GAS. After an asymptomatic
interim period, the onset of ARF is often accompanied by minor manifestations of the disease including fever, arthralgias, elevated acute phase reactants, and a prolonged PR interval on ECG. These are non-specific and can be found in multiple other
conditions.Arthritis is the most common of the major manifestations, occurring in 70% of patients with ARF. The arthritis primarily affects large joints, such as the knees and ankles, and is different from the arthritis in most other rheumatologic diseases in that it is migratory in nature. It often comes and goes and will involve different joints over time. The arthritis of ARF responds well to treatment with ASA or other NSAIDs.
Carditis is the next most common major manifestation and occurs in approximately half of the children with ARF. . . . The valves most commonly involved in RHD are the mitral and aortic valves. Mitral insufficiency is characterized by a holosystolic ejection murmur that can be best heard in the left lateral decubitus position over the apex of the heart, with radiation to the left axilla. Aortic regurgitation is a diastolic murmur that is best heard over the third left intercostal space with the patient leaning forward in end expiration.
Valvular insufficiency leads to valvular stenosis from scarring during the chronic stages of rheumatic heart disease and can result in acute heart failure in 5% of children.
Thus, carditis is aggressively treated with high dose aspirin for at least 4-8 weeks depending on clinical response. Other NSAIDs are not yet recommended by experts for treatmentof carditis.
In cases of severe carditis with congestive heart failure, oral prednisone monotherapy for 2 weeks (with tapering over the following 2-3 weeks) is the preferred treatment option. To prevent rebound of symptoms upon the withdrawal of steroids,
aspirin therapy is commenced one week prior to the termination of prednisone.Sydenham chorea* is an extrapyramidal movement disorder that results from CNS inflammation of the basal ganglia and caudate nucleus. It is characterized by dance-like involuntary jerky movements involving the distal extremities, as well as the tongue and face, which are usually symmetric. While frustrating for the patient, these symptoms are usually self-limiting and spontaneously resolve in a few weeks.
*Here are links to three YouTube videos showing Sydenham Chorea:
- Boy with Sydenham’s Chorea
Jan 14, 2014 - Sydenham Chorea
Mar 24, 2013- Jerky speech
- Chorea
- “Chorea involves both proximal and distal muscles. In most patients, normal tone is noted, but, in some instances, hypotonia is present. In a busy movement disorder center, levodopa-induced chorea is the most common movement disorder, followed by Huntington disease (HD). [1]”
- Pronator sign
- “The ‘pronator sign’ is hyperpronation of the hands, with the palms facing outward when the arms are held over the head.”
- Tongue Fasciculations
- Tongue Fascilations-YouTube Video
- Ballismus
- ‘Ballism or ballismus is considered a very severe form of chorea in which the movements have a violent, flinging quality. In Greek, ballismos means “a jumping about or dancing.” [2] Ballism has been defined as “continuous, violent, coordinated involuntary activity involving the axial and proximal appendicular musculature such that the limbs are flung about.”‘
