Ankylosing Spondylitis (AS) is one of many forms of chronic inflammatory and degenerative arthritis, affecting the spine A.S. especially affects the joints between the vertebrae of the spine and the joints between the spine and the pelvis (sacro-iliac joints). It may also affect other joints of the body. The joints are initially inflamed and this may be followed by progressive stiffness and inflexibility.
Ankylosing-Spondylitis is commonly misspelled as ankylosing spondyliti, anyklosing spondylitis, ankylosing spondylitiis, ankylosig spondylitis, ankyllosing spondylitis.
Ankylosing-Spondylitis is called as achalatakarak kasherukashoth in Hindi and maakyanna aleli suja in Marathi.
It eventually leads to the fusion of the spine, giving permanent painful stiffness of the back. It is often called bamboo spine, as the spine tends get stiff like a bamboo. This condition is more common in males as compared to females and usually occurs in individuals between 16-40 years of age.
The sacroiliac joints are located in the low back where the sacrum (the bone directly above the tailbone) meets the iliac bones (bones on either side of the upper buttocks). Due to chronic inflammation in these areas there are symptoms like pain and stiffness of spine. As this condition is chronic one with time this leads to fusion of the vertebrae i.e. complete cementing together of vertebrae.
This process is known as Ankylosis. Due to this condition there is loss of mobility if spine. The stiffness could eventually be very severe making the spine resembling a bamboo. Hence it is also called bamboo spine.
Ankylosing spondylitis can affect other tissues throughout the body. It can cause inflammation in or injury to other joints away from the spine, as well as other organs, such as the eyes, heart, lungs, and kidneys.
The exact cause of Ankylosing spondylitis is not understood. It has been considered to be an autoimmune disease (like many others such as Diabetes, Rheumatoid Arthritis, Alopecia Areata, Thyroiditis, etc.). Genetic factors are likely to be involved. The majority of people with Ankylosing spondylitis have a gene called HLA-B27. However, the presences of HLA-B27 (Human Leukocyte Antigen B27) is not absolutely diagnostic of AS.
AS has a strong genetic factor as a cause behind its development. About 90 % of patients with AS are born with HLA B27 gene. There are blood tests to detect HLA-B27 gene marker. The HLA-B27 gene appears only to increase the tendency of developing Ankylosing spondylitis, while some additional factor(s), perhaps environmental, are necessary for the disease to appear or become expressed.
Interestingly, the presence of HLA-B27 alone does not make one prone to develop this disease. As per a study, about 7% of the United States populations have the HLA-B27 gene, only 1% of the population actually has the disease Ankylosing spondylitis.
In Northern Scandinavia (Lapland), 1.8% of the population have Ankylosing spondylitis while 24% of the general population have the HLA-B27 gene. Even among HLA-B27 positive individuals, the risk of developing Ankylosing spondylitis appears to be further related to heredity. In HLA-B27-positive individuals who have relatives with the disease, their risk of developing Ankylosing spondylitis is 12% (six times greater than for those whose relatives do not have Ankylosing spondylitis).
Autoimmunity is considered significantly involved in the development of AS. Again, autoimmunity itself may be genetically oriented.
Prolonged stressful situation in one's life could possibly trigger the underlying genetic tendency for AS.
Bacterial infection triggering AS is one of the other theories.
Recently, two more genes have been identified that are associated with Ankylosing spondylitis. These genes are called ARTS1 and IL23R. These genes seem to play a role in influencing immune Function. It is anticipated that by understanding the effects of each of these known genes researchers will make significant progress in discovering a cure for Ankylosing spondylitis.
How does inflammation occur and persist in different organs and joints in Ankylosing spondylitis is a subject of active research. Each individual tends to have their own unique pattern of presentation and activity of the illness. The initial inflammation may be a result of an activation of body's immune system by a bacterial infection or a combination of infectious microbes. Once activated, the body's immune system becomes unable to turn itself off, even though the initial bacterial infection may have long subsided. Chronic tissue inflammation resulting from the continued activation of the body's own immune system in the absence of active infection is the hallmark of an inflammatory autoimmune disease.
The most significant symptoms of AS are pain in lower back, painful stiffness and immobility of back.
The totality of symptom may be described as under: