From Sore Throat to Heart Disease

(RHEUMATIC HEART DISEASE)

Rheumatic heart disease is a permanent heart valve damage resulting from one or repeated episodes of rheumatic fever. Acute rheumatic fever is an abnormal immune response by the body to an infection (usually a throat infection) caused by bacteria called group A streptococci. Normally, one of the ways in which the body fights infections is by producing antibodies which attack the infecting organisms. In acute rheumatic fever, the antibodies produced are thought to also attack the host’s tissues (brain, skin, subcutaneous tissues, joints and heart) causing an inflammatory damage several weeks after the throat infection. This autoimmune response is seen in about 0.3-30% of patients with untreated or poorly treated group A streptococcal throat infection. Rheumatic heart disease is the most serious complication of rheumatic fever. Almost half of patients with acute rheumatic fever will have the heart involvement. 
                                             

The most commonly affected valve is the mitral valve followed by the aortic valve. Other valves (tricuspid and pulmonary are less frequently affected).The damage causes the flaps of the valve to thicken causing narrowing of the valve opening (stenosis). Repeated episodes of rheumatic fever further damage the valves and eventually lead to heart failure as less blood is pumped out of the heart but rather backs up in the left atrium, pulmonary veins and lungs. At this stage, except the valves are replaced with prosthesis, the patient will die of consequences of the heart failure. During an acute episode of rheumatic fever, the valvular damage may be minor and still be reversible. Symptoms of rheumatic heart disease include: shortness of breath, fatigue, irregular heartbeats, chest pain and fainting.

Rheumatic fever is principally a childhood disease; sore throat in children should therefore be taken seriously especially if there are no symptoms suggesting that it’s viral in origin. Such symptoms include runny nose, itchy eyes and other symptoms of the common cold. On the other hand, symptoms and signs which are considered as hall marks of streptococcal sore throat include a history of close contact with infected person, tender lymph nodes, skin rash (scarlet fever), swollen tonsils with whitish exudates and abdominal pain, with or without fever.

However, the most reliable way to distinguish between a viral and a streptococcal sore throat is to have a throat swab and culture done to directly identify the streptococcal organisms if present.

An episode of acute rheumatic fever can go unnoticed. Symptoms however include fever, pain and swelling of the joints, nausea, stomach cramps and vomiting. These symptoms may be non specific, making diagnosis difficult. Thus the “Jones criteria” were developed to help doctors in diagnosing rheumatic fever.  The major criteria include: carditis, polyarthritis, chorea, subcutaneous nodules, and erythema marginatum. Minor criteria include: previous rheumatic fever or rheumatic heart disease, arthralgia, fever, elevated erythrocyte sedimentation rate/positive C-reactive protein/ leukocytosis, and prolonged PR interval on an electrocardiogram. Two major criteria, or a combination of one major and 2 minor, provide reasonable evidence for a diagnosis of rheumatic fever.

RHD occurs all over the world but is more prevalent in developing countries in association with overcrowding; which facilitates the spread of the throat infection, poverty; which partially explains the untreated or poorly treated infections, and lack of access to health care facilities in some areas.

There are 2 levels of prevention of rheumatic heart disease. The first is Primary prevention. This involves the prompt administration of antibiotics (Penicillin) for suspected strep sore throat. It prevents the development of acute rheumatic fever. The other is Secondary prevention. The aim is to prevent recurrent episodes of rheumatic fever in someone who has already had a first episode. This will reduce progression of heart disease. Secondary prevention is more difficult because it involves the use of penicillin orally (daily) or as injection (monthly) continuously for at least 10 years after the episode of acute rheumatic fever. 

The lessons here are these:

• An “ordinary” sore throat may not be so ordinary after all

• A stitch in time saves nine [and in this case, saves the entire garment]