Monday, June 25, 2012

What Is Rheumatic Fever? What Causes Rheumatic Fever?

Rheumatic fever is an inflammatory disease that may develop as a complication of a streptococcus infection, such as strep throat or scarlet fever (caused by Streptococcus pyogenes or group A beta-hemolytic streptococcus). If it does develop, it will usually do so two to three weeks after the Group A streptococcal infection.

Rheumatic fever mainly affects children aged between 5 and 15 years; however, it can affect adults and younger children. Boys and girls have the same risk of developing the disease; girls and women tend to have more severe symptoms. The disease may cause long term effects on the skin, heart, brain and joints. Rheumatic fever may cause permanent damage to the heart valves (rheumatic heart disease). Rheumatic fever has the potential to cause heart failure, stroke and even death.

Even though there is no current cure for rheumatic fever, antibiotics, anti-inflammatory drugs and anticonvulsants may be used to relieve symptoms and prevent recurrences.

The disease is fairly rare in most developed nations, but is still common in many other parts of the world, particularly in sub-Saharan Africa, south central Asia, and the indigenous population of Australia and New Zealand. Before the widespread introduction of antibiotics and increased levels of public sanitation and living standards, rheumatic fever used to be one of the leading causes of acquired heart disease in developed nations.

The National Health Service (NHS), UK, estimates that approximately 1 in every 100,000 people is affected by rheumatic fever in England annually.

Patients aged between 25 and 35 years may have recurring episodes of rheumatic fever.

According to Medilexicon's medical dictionary:
    Rheumatic Fever is " a subacute febrile syndrome occurring after group A β-hemolytic streptococcal infection (usually pharyngitis) and mediated by an immune response to the organism; most often seen in children and young adults; features include fever, myocarditis (causing tachycardia and sometimes acute cardiac failure), endocarditis (with valvular incompetence, followed after healing by scarring), and migratory polyarthritis; less often, subcutaneous nodules, erythema marginatum, and Sydenham chorea; relapses can occur after reinfection with streptococci."

What are the signs and symptoms of rheumatic fever?

A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.

According to The Mayo Clinic (USA), rheumatic fever signs and symptoms generally develop 2 to 4 weeks after a streptococcal throat infection (1 to 5 weeks according to the National Health Service, UK).

As you can see below, there are many possible signs and symptoms linked to rheumatic fever - a patient will not necessarily have them all:
  • Arthritis (joint pain and swelling) - generally starts in the knees and ankles, and then works its way to other joints in the body
  • Bumps and lumps (nodules) under the skin
  • Chest pain
  • Chorea - uncontrollable jerking of knees, elbows, wrists and ankles
  • Headache
  • High fever - above 39C (102F)
  • Inappropriate crying or laughing
  • Irritability, moodiness
  • Nosebleeds
  • Pain in one joint that migrates to another joint
  • Pain in the abdomen
  • Palpitations - sensation that the heart is fluttering or pounding hard
  • Panting (shortness of breath)
  • Red blotchy skin rash
  • Short attention span
  • Sweating
  • Tiredness (fatigue)
  • Vomiting
  • Weight loss

What are the risk factors for rheumatic fever?

A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2.
  • Genetics - some individuals possibly carry genes (or a gene) that make them more susceptible to developing rheumatic fever. A person with a family history of rheumatic fever has a higher risk of developing it himself/herself.
  • Type of strep bacteria - some strep bacteria strains are more likely to lead to rheumatic fever than others.
  • Environment - such factors are overcrowding, poor sanitation and poor access to healthcare increase the risk of rheumatic fever.

What are the causes of rheumatic fever?

Rheumatic fever may develop as a complication after a throat infection with Streptococcus pyogenes, or group A streptococcus (a bacterium). Strep throat, and less commonly scarlet fever are infections caused by Group A streptococcus infections. Group A streptococcus skin infections, as well as infections in other parts of the body may lead to rheumatic fever (much less common).

Although experts are not completely sure what the link between strep infection and rheumatic fever is, they believe that the bacterium upsets the patient's immune system. Strep bacteria have a protein which is similar to one found in some tissues in our body. Immune system cells that would usually target the bacterium may subsequently start attacking the body's own tissues, as if they were toxins or infectious agents; especially tissues of the heart, joints, CNS (central nervous system) and skin, resulting in inflammation.

Inflammation can cause the following symptoms:
  • Inflammation of the heart - chest pain, fatigue, shortness of breath
  • Inflammation of the joints - arthritis symptoms
  • Inflammation of the skin - skin rashes and nodules
  • Inflammation of the CNS (central nervous system) - chorea (jerking), personality changes
If the patient who is infected with strep bacteria takes the complete antibiotic treatment, the chances of rheumatic fever developing are negligible (zero or tiny). However, if the patient has at least one episode of untreated strep throat or scarlet fever, his/her risk of developing rheumatic fever increases significantly.

Diagnosis of rheumatic fever

According to the National Health Service (NHS), UK, there are so many different rheumatic fever symptoms that a checklist is needed to help in the diagnosis process - this checklist is called the Jones Criteria. The Jones Criteria involves checking whether the patient has specific signs and symptoms strongly linked to rheumatic fevers. These signs and symptoms are collectively known as criteria.

There are two types of criteria:
  • Major criteria - signs and symptoms are strongly linked to rheumatic fever. They include:

    • Inflammation of the heart (carditis)
    • Several joints have become swollen, painful and stiff (polyarthritis)
    • The patient has jerky involuntary movements (chorea)
    • There is a red or pink skin rash (erythema marginatum)
    • There are small nodules (lumps and bumps) under the skin, especially on the elbows, ankles, knees and knuckles (subcutaneous nodules)
  • Minor criteria - signs and symptoms are moderately linked to rheumatic fever:

    • The patient has joint pain, but it is not as severe as arthritis joint pain (arthralgia)
    • Elevated body temperature - usually over 102F (39C)
    • Elevated erythrocyte sedimentation rate (ESR) and C reactive protein (CRP) - types of blood tests that detect inflammatory conditions
    • Irregular heart rhythm
A confident rheumatic fever diagnosis can be made if:
  • Two or more major criteria are detected
  • One major and two minor criteria are detected
Some of the signs and symptoms may be detected just by examining and interviewing the patient. Others will require testing. Testing may include:
  • ECG (electrocardiogram) - up to 12 adhesive electrodes are attached to the skin on certain parts of the body, usually the arms, legs and chest. The ECG (a device) measures the electrical activity of the patient's heart, revealing any possible abnormalities in heart rhythms. Abnormal heart rhythms usually occur when there is inflammation of the heart - a common complication of rheumatic fever. Early detection with subsequent prompt treatment is important.
  • Electrocardiography - this device uses sound waves that produce images of the heart. The test enables the doctor to see whether there is any inflammation of the heart. Heart valve damage, if present, may also be revealed in this test (much less likely early on in the disease).
  • Blood tests

    • CRP rates - blood tests can detect higher-than-normal levels of CRP (C reactive protein), which is produced by the liver. High CRP blood levels means there is inflammation.
    • Erythrocyte sedimentation rate (ESR) - a sample of red blood cells are placed in a test tube of liquid, their rate of descent is measured. If the cells descend faster than normal it could mean the patient has an inflammatory condition.
    • Test for strep infection - if the patient has already been diagnosed with a strep infection the doctor may not order additional tests.

What are the treatment options for rheumatic fever?

The medical team's aims are to destroy the bacteria, relieve symptoms, control inflammation and prevent recurrences of rheumatic fever.

Antibiotics - the patient, usually a child, will probably be prescribed penicillin or some other antibiotic to destroy any remaining strep bacteria in the body.
  • Preventing recurrence - after completing the full course of antibiotics, the patient will be prescribed another course of antibiotics to prevent recurrence. This preventive treatment will generally continue until the patient is about 20 years old. If the patient is older, for example a teenager when rheumatic fever develops for the first time, preventive treatments may continue beyond the age of 20 years.
  • Heart inflammation - some patients may be advised to continue taking preventive antibiotic treatment for much longer, in some cases for the rest of their lives.

    It is important to get rid any streptococcocal bacteria. If any is left inside the body and the patient has another throat infection, there is a serious risk of a recurrence of rheumatic fever. Repeated occurrences of rheumatic fever significantly raise the risk of heart damage (sometimes permanent).
Anti-inflammatory treatment - an anti-inflammatory drug, such as or naproxen (Anaprox, Naprosyn, etc.) may be prescribed. These medications reduce pain, inflammation and fever. A corticosteroid, such as prednisone may be prescribed if the patient does not respond to anti-inflammatory medications or there is inflammation of the heart.

Aspirin is not usually recommended for children aged less than 16 years because there is a risk of developing Reye's syndrome, which can cause liver and brain damage, and even death. However, an exception is usually made when the child has rheumatic fever because the dose is small and the results are very good - in other words, the benefits are far greater than the risks.

Anti-convulsant medications - if chorea symptoms are severe an anticonvulsant, such as valproic acid (Depakene, Stavzor) or carbamazepine (Carbatrol, Equetro) may be prescribed.

Long term care - any child who had rheumatic fever will need to know later on that he/she once had rheumatic fever. As an adult the individual should discuss this with his/her doctor. Heart damage from rheumatic fever may not appear for many years after the illness.

What are the possible complications of rheumatic fever?

Rheumatic fever symptoms, specifically inflammation, may persist for several weeks, months, and in some cases much longer, causing long-term problems.

Rheumatic heart disease - the most common and most serious complication. According to the National Health Service (NHS), UK, an estimated 9% to 34% of rheumatic fever cases have this complication. Rheumatic heart disease means permanent damage to the heart caused by the inflammation of rheumatic fever. The most common complication occurs with the mitral valve - the valve between the two left chambers of the heart. Sometimes other valves may also be affected. The following conditions may result:
  • Valve stenosis - the valve narrows, causing a drop in blood flow.
  • Valve regurgitation - blood flows in the wrong direction because of a leak.
  • Heart muscle damage - inflammation can weaken the heart muscle, leading to improper pumping function of the heart.
These conditions may also develop if there is damage to heart tissue, and/or damage to the mitral valve or other heart valves:
  • Heart failure - even though it may sound like it, heart failure does not necessarily mean that the heart has failed. Heart failure is a serious condition in which the heart is not pumping blood around the body efficiently. The patient's left side, right side, or even both sides of the body can be affected.
  • Atrial fibrillation - the human heart has two upper chambers and two lower chambers. The upper chambers are called the left atrium and the right atrium - the plural of atrium is atria. The two lower chambers are the the left ventricle and the right ventricle. When the two upper chambers - the atria - contract at an excessively high rate, and in an irregular way, the patient has atrial fibrillation.

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