Rheumatic fever

Rheumatic fever: description

Rheumatic fever is an autoimmune reaction triggered by certain bacteria called beta-hemolytic streptococci. In an infection with these pathogens, attacks the body’s immune system and targeted to certain surface structures of the bacteria. For this purpose, the immune system forms so-called antibodies, small proteins that bind specifically to the surface of pathogens and make them recognizable to immune cells. The immune cells finally make the invaders harmless.

After the immune system has formed antibodies against a specific pathogen, they remain in the body for a longer time, even if the actual disease has already recovered. Re-infection with the same pathogen can counteract the immune system so quickly and effectively.

However, sometimes it happens that antibodies not only recognize foreign material but also falsely bind to the body’s own structures, such as the surface of the heart valves. This tissue is thus marked as alien to the rest of the immune system and it comes to a defense reaction against the body. This is called an autoimmune reaction, a reaction against oneself.

In general, this happens only rarely, certain pathogens, such as beta-hemolytic streptococci, however, are known to be able to trigger autoimmune reaction. They have a surface texture that is similar to certain body structures. The antibodies “confuse” their goal, so to speak, (“molecular mimicry”). In the context of rheumatic fever, especially heart, joint and skin cells are affected by the misdirected immune response.

How common is rheumatic fever?

Only a very small proportion of people infected with beta-hemolytic streptococci subsequently develop a rheumatic fever. In countries with good medical care, this complication can often be prevented by the right treatment. However, in many developing countries, rheumatic fever is much more common and the most common cause of heart disease in children. Worldwide, nearly half a million people suffer from rheumatic fever each year, including children and adolescents aged between 3 and 16 years.

Rheumatic fever: symptoms

In rheumatic fever, there are acute complaints that occur days to weeks after the streptococcal infection. Long-term effects of rheumatic fever continue to cause problems for years to decades after infection with streptococci. These long-lasting and later onset symptoms are mostly due to the structural damage to the organs, which is difficult to prevent.

Acute rheumatic fever

Acute rheumatic fever usually occurs several weeks after streptococcal infection. The disease can present itself very differently and is not easy to recognize, because not all symptoms always appear the same. Many sufferers come to the doctor with fever, weakness and fatigue. Small children complain in part in addition to abdominal pain. Also, pain in the large joints, such as the knee, hip or shoulder are typical complaints that occur in rheumatic fever. The joints often not only hurt, but are also red and swollen.

A fast pulse, often with chest pain on light loads, may be an indication of inflammation of the heart. A tribal, itchy rash and small nodules under the skin are other signs of rheumatic fever. These skin conditions are not always present, but can additionally occur when the heart is affected.

Finally, in a rheumatic fever, the immune system can also attack the nervous system. It sometimes comes to personality changes, muscle weakness, balance problems and disorders of fine motor skills. Infestation of the brain can lead to a special movement disorder, the so-called Sydenham chorea. Children are much more affected by this neurological syndrome than adult patients.

Typical of the Chorea Sydenham are uncontrolled, aimless movements. The children behave awkwardly, they spill soup or break plates. Unlike with the heart inflammation, the neurological symptoms heal usually without consequences. For example, the Chorea Sydenham is usually only for a few months.

Long-term consequences of rheumatic fever

The long-term effects of rheumatic fever are usually more likely to affect adults over 30 years. These chronic complaints are expected when patients become ill with a severe rheumatic fever during their childhood. Even at an older age, they can then repeatedly suffer from attacks with increasing physical limitations. It is unlikely, however, that a rheumatic fever will affect adults for the first time without having occurred in childhood.

Damage to the heart as part of a rheumatic fever is relatively common and often lasts a lifetime. Up to 60 percent of those affected show long-term damage to the heart. This applies in particular to late-diagnosed or untreated patients. The immune system attacks especially the heart valves. These work like a valve and guarantee that the heart pumps the blood continuously in one direction. If the heart valves break, this leads to a chronic overload and finally to pumping failure of the heart.

Rheumatic fever: causes and risk factors

The cause of the autoimmune reaction is beta-hemolytic streptococcus group A. Behind this complex name hides a relatively common pathogen, which particularly likes to settle in the pharynx and there leads to an inflammation. A crimson pharyngeal mucosa with small yellow plaque is the result (streptococcal angina). Also, the childhood disease scarlet fever is caused by streptococci, as well as various skin infections.

Why some people have a rheumatic fever after a streptococcal infection and not in others is not completely clear. It is believed that some susceptibility to such a malfunction of the immune system is inherited.

Another important risk factor is age. Rheumatic fever in children is much more common than in the elderly. This risk is particularly high between the ages of five and fifteen, as streptococcal throat infections are more frequent during this period.

Other risk factors are poor sanitary and poor living conditions, along with inadequate medical care. Until the 1950s, rheumatic fever was also the most common inflammatory rheumatic disease among schoolchildren and adolescents in Germany. Thanks to consistent and timely antibiotic therapy, the number of cases has fallen sharply.

Rheumatic fever: examinations and diagnosis

The physician always has to think about a rheumatic fever when a child or adolescent with high fever and joint pain comes along and also had a sore throat in recent weeks. However, it is not always easy to recognize the rheumatic fever, as the symptoms may be very different in many patients.

As a diagnostic aid serve the doctor the so-called Jones criteria, which were developed in 1944. They describe symptoms that together indicate a rheumatic fever. Main criteria include:

• Joint pain (arthritis)
• Carditis (heart muscle inflammation)
• Rash (especially on the trunk)
• Small nodules under the skin (especially on the elbows, wrists, knees and Achilles tendons)
• Chorea Sydenham (movement disorder)

In addition, there are some minor criteria, such as increased levels of inflammation in the blood, fever, ECG changes or evidence of streptococci in recent weeks.

To prove the pathogen, the doctor can perform a special rapid test for acute sore throat. To do this, he makes a throat swab, which clarifies within a few minutes whether beta-hemolytic group A streptococci are responsible for the inflammation.

If symptoms of rheumatic fever already exist, but the acute pharyngeal infection has already been cured, there are other ways of proving the pathogens. With the so-called antistreptolysin titer (ASL titer) and the anti-DNase B titer (ADB titer), it is possible to search the blood for signs of an immune reaction against the triggering bacteria.

According to a certain decision-making catalog, one can use the Jones criteria to diagnose rheumatic fever. In general, the more factors are met, the more likely a rheumatic fever is, with major criteria more significant. Further clinical and imaging examinations help on the way to the diagnosis. To estimate possible heart damage, the doctor uses ultrasound and electrocardiography (ECG).

Rheumatic fever: treatment

The main element of treatment of rheumatic fever is antibiotic therapy. On the one hand, it significantly reduces the risk of rheumatic fever after infection with beta-hemolytic streptococci. On the other hand, if there are already the first signs of this, one can reduce the further progression of rheumatic fever and a risk of long-term damage by up to 80 percent. The most important antibiotic in the fight against rheumatic fever is penicillin. Depending on the case, other antibiotics such as cephalosporins or macrolides are used.

If the heart is involved, anti-inflammatory drugs such as ibuprofen or naproxen are also used as soon as the diagnosis is confirmed. In addition, steroids are administered if the heart is severely impaired. Whether they bring a long-term improvement, or only acutely fight the symptoms is controversial. It is also important that the patients avoid any physical stress.

If there is a long-term closure of the heart valves, surgery may be necessary to either reopen the valve or replace it completely. However, such an intervention can be performed at the earliest one year after the acute inflammatory phase.

Depending on the degree of damage to the heart, the patients must also take a long-term antibiotic protection, in case of severe heart damage even life. This can be given in tablet form or by syringe every few weeks. The long-term therapy prevents a renewed flare-up of the disease and thus protects against more serious long-term damage.

Rheumatic fever: disease course and prognosis

Disease progression and prognosis of rheumatic fever depend in particular on how fast it is recognized and adequately treated. If an antibiotic treatment already during the pharyngitis, the rheumatic fever can usually be avoided. Even though the rheumatic fever is still in its early stages, the prognosis is good. It usually heals without further problems. The joint complaints sound over a longer period of time.

However, if a heart damage has already occurred, it can usually no longer be repaired. In addition, the risk of another episode of rheumatic fever increases, which can aggravate the damage. It is therefore advisable to go to the doctor in case of severe sore throat, or fever with joint pain with the ill child and to have a quick streptococcal test.