Reactive arthritis (Reiter's syndrome)The reactive arthritis (formerly also known as Reiter's syndrome) is an inflammatory disease that mainly affects the joints. It occurs for a few days to a few weeks as a result of a bacterial infection of the gastrointestinal tract or the urinary tract.
Reactive arthritis is classified as one of the so-called Spondylarthritides counted. These are five different inflammatory diseases of joints or the spine that are clinically similar but have a different cause. All of them belong to autoimmune diseases: There is an attack by the immune system against the body's own cells. In the case of reactive arthritis, the immune system attacks components of the bacteria that settle in the joints during infection from the gastrointestinal tract or urinary tract.
Reactive arthritis most commonly affects fair-skinned males between the ages of 15 and 35. In addition, a genetic peculiarity seems to significantly increase the risk of the disease.
The term formerly used Reiter's Syndrome refers to the first discoverer of the disease, the German bacteriologist Hans Reiter. He lived from 1881 to 1969 and was president of the Reich Health Office under National Socialism from 1933 to 1945. Among other things, he was involved in planning typhus experiments on prisoners in the Buchenau concentration camp. Therefore, the term Reiter's syndrome is nowadays replaced by the term reactive arthritis.
Other names for the clinical picture are arthritis urethritica or venereal arthritis (at origin as a venereal disease), Polyarthritis enterica (when originating from an intestinal infection) or Fiessinger-Leroy syndrome.
Reactive arthritis occurs as Secondary disease after a bacterial infection mostly from the gastrointestinal tract or urethra. After fighting the initial disease, components of the pathogens enter the joints and are recognized by the body's immune system as foreign. The immune system attacks the affected tie. Reactive arthritis is therefore classified as an autoimmune disease (a disease in which the immune system produces antibodies against the body's own cells).
The reaction of the immune system leads to Inflammation with swelling, redness, warmth and pain. The pathogens themselves are usually not detectable in the synovial fluid of affected joints, but building blocks of their genetic material, such as DNA or RNA.
According to the underlying disease, the following pathogens can be considered as the original triggers of the infection that results in reactive arthritis:
Inflammation of the urinary tract as a sexually transmitted disease caused by gonococci, chlamydia, mycoplasma or ureaplasma inflammation of the gastrointestinal tract by shigella, yersinia, salmonella, campylobacter or other germs
This does not at all mean that one should expect reactive arthritis after an intestinal or urinary tract infection. Only about one in 30.000 people contract the disease each year. However, certain bacteria such as chlamydia increase the risk significantly.
In addition, the development of reactive arthritis is thought to be caused by a genetic predisposition. About 75 percent of those affected are HLA-B27 positive in the blood test. HLA-B27 belongs to a group of proteins that are located on the surface of almost all cells in the human body. Such proteins are involved in the body's immune response. If a person is HLA-B27 positive, this means that he or she has a gene that leads to the formation of HLA-B27 as the surface structure of cells.
Reactive arthritis can basically be contracted by anyone. However, it most often affects people between 15 and 35 years of age and tends to affect men more than women. Fair-skinned people are affected more often than people with darker skin color. Another risk factor is the genetic alteration on the HLA-B27 gene. Affected individuals are more likely to develop autoimmune diseases than people without this genetic feature.
An increased risk of developing an infection of the gastrointestinal tract or urinary tract, from which reactive arthritis may develop, results from:
unprotected sexual intercourse (sexually transmitted pathogens such as chlamydia) consumption of undercooked chicken or pork meat (germs such as salmonella)
Reactive arthritis develops as a result of bacterial inflammation of the intestine or urinary tract. Depending on the cause, the symptoms of the respective infection appear first, for example:
– frequent urination – painful urination
In many cases, however, the original infection is not noticed by the patient.
A few days to several weeks later, the symptoms of reactive arthritis appear. These can typically include:
joint inflammation (Arthritis): One or more joints are affected, often knee or ankle joint. The joints are warm, swollen and painful. Conjunctivitis (conjunctivitis) with redness, burning, tearing, sensitivity to light of the eyes Urethritis (Urethritis; the urethra is a tube-shaped organ that carries urine from the bladder to the outside of the body) with pain during urination
Other possible symptoms are:
inflammation of the skin (dermatitis) keratinization of the skin on the soles of the feet and palms of the hands psoriasis-like changes of the glans penis (balanitis) changes in the fingernails
Inflammation of the tendons (especially of the Achilles tendon) inflammatory change in the area of the lower spine (joint between the sacrum and the ilium), which can lead to severe postural deformities inflammation inside the eyes (Uveitis, Iritis)
A tentative diagnosis can be made on the basis of the typical symptoms of joint inflammation (arthritis), conjunctivitis (conjunctivitis) and ureteritis (urethritis). Often, skin changes due to the disease also give decisive indications of reactive arthritis. Especially if patients have had a previous intestinal or urinary tract infection, reactive arthritis is suspected.
If the patient is HLA-B27 positive in the blood test and suffers from the described symptoms, this speaks for the diagnosis of. X-ray examinations can be used to visualize the extent of the joint inflammation.
Swabs from the urethra or urine samples are examined to detect pathogens, especially chlamydia, which can trigger reactive arthritis. This is important to initiate therapy with an appropriate antibiotic. As a rule, no pathogens can be detected in the synovial fluid.
On the one hand, treatment is directed against the underlying intestinal infection or urinary tract disease. The pathogens are specifically combated with antibiotics, if proof of the pathogen can be provided.
The therapy of reactive arthritis itself is symptomatic. Joint discomfort can be treated as follows:
anti-inflammatory drugs and painkillers such as ibuprofen, diclofenac, cortisone immobilization of the joints
specific exercises for the joints
If the eyes are affected, eye drops with anti-inflammatory, pain-relieving agents are used. Cortisone is given especially in the case of disease inside the eye.
If the reactive arthritis progresses chronically, the administration of drugs that suppress the immune system (immunosuppressants such as methotrexate) may be necessary.
The prognosis of reactive arthritis varies greatly. In some patients, the symptoms disappear completely after a few weeks to months. In half of those affected, however, they reoccur after a period of time. Then it is usually only a matter of individual symptoms such as conjunctivitis.
About 20 percent of patients develop a chronic course of the disease and have joint problems, back pain or tendon pain in the long term. Patients with an HLA-B27 gene defect are particularly affected by a severe course of the disease.
The development of reactive arthritis is a consequence of bacterial gastrointestinal or urinary tract infections. One can protect oneself from this to a limited extent by:
– protected sexual intercourse (condoms) – sufficient cooking of pork and poultry meat – refraining from eating raw eggs – hygiene after going to the toilet
The prophylactic measures are particularly recommended for people who are known to have the HLA-B27 gene.
In order to prevent a serious course of reactive arthritis, the inflammation should be adequately treated. If joint inflammation persists for a long time, there is a risk that the joints will be permanently damaged. If inflammation of deeper eye layers is not treated, damage up to blindness can result from it.