A 10-year-old boy is brought to the office with a chief complaint of whole body aches and stomach pain that have progressively been getting worse over the past three days. He reports a sore throat which has made it difficult to swallow. His past medical history includes a few cases of the common cold and an ear infection. He had previously been seen at another clinic a month ago for his sore throat which was diagnosed as a viral infection and thus went untreated. He is not currently on any medications. His temperature is currently 102°F (38.8°C) with a heart rate of 125 beats/minute. Physical examination shows a normal pharynx. On cardiac auscultation, a murmur is heard over the mitral valve area as well as a friction rub. He is admitted to the inpatient setting for further assessment. An echocardiogram shows pericarditis but no other structural abnormalities. His blood work shows increased white blood cell count, elevated C-reactive protein (CRP), and elevated erythrocyte sedimentation rate (ESR). He is started on long-acting intramuscular penicillin G benzathine to treat the suspected causative agent.
Secondary prophylaxis with antibiotics is used to decrease the risk of which of the following complications?
D) Rheumatic heart disease
This patient has acute rheumatic fever (ARF). If left untreated, ARF can progress to rheumatic heart disease which can lead to permanent heart damage such as valve stenosis, valve regurgitation, and damage to other cardiac tissues. This patient has evidence of cardiac involvement. Rheumatic heart disease becomes more severe with each recurrent episode, so the most effective method to limit progression is prevention of recurrent group A streptococcal pharyngitis.
The diagnostic criteria for ARF include five major and four minor manifestations (Revised Jones Criteria).
The five major manifestation are:
- Arthritis (usually migratory polyarthritis predominantly involving large joints)
- Carditis and valvulitis
- Central nervous system involvement such as Sydenham chorea
- Subcutaneous nodules
- Erythema marginatum
The four minor manifestations are:
- Arthralgias
- Fever
- Elevated acute phase reactants
- Prolonged PR interval on electrocardiogram
Answer choices A, B,and E are incorrect. Although these choices are also aspects of the JONES criteria (Erythema Marginatum, Joints, and Sydenham Chorea respectively) these are manifestations of ARF and are not prevented with antibiotic treatment. complications are less life threatening.
Answer choice C is incorrect. Pneumonia is not a complication of acute rheumatic fever.
Key Learning Point
Rheumatic fever is an inflammatory sequelae of infection from group A Streptococcus (GAS). This is primarily a disease of childhood and adolescence. Inflammation occurs because the M protein of GAS causes a type II hypersensitivity reaction whereby antibodies are made against the protein. These antibodies can cross react with proteins in the body leading to complications described in the diagnostic survey called the JONES criteria. Each letter describes a major criteria that can be used to diagnose Rheumatic fever: J - joints, O - Obvious heart damage, N - Nodules, E - Erythema marginatum, S - Sydenham chorea. Minor criteria include arthralgia, fever, increased acute phase reactants, and a prolonged PR interval on ECG. The presence of 2 major criteria, or 1 major and 2 minor criteria with positive evidence of GAS infection can be used to diagnose ARF.
