Ankylosing Spondylitis – Symptoms, Diagnosis And Treatment
Ankylosing spondylitis is a chronic inflammatory systemic disease, with incompletely elucidated etiology, which typically installs in the sacroiliac joints (sacroiliitis) and those of the spine, with evolution to fibrosis, ossification, strain and ankylosis. Peripheral joints and extra-articular structures may be affected, but less frequently. The prevalence of ankylosing spondylitis in Caucasians is 0.5% -1%, with male / female ratio of 3-4/1. Illness begins most frequently in the second, the third and fourth decade of life.
Ankylosing Spondylitis Causes
So far, different studies did not clear the etiologic agent of ankylosing spondylitis. However, some characters of ankylosing spondylitis are common with those of arthritis in some inflammatory bowel diseases (ulcerative colitis, Crohn’s disease). Elevated titers of anti-Klebsiella pneumoniae antibodies and coprocultures which are frequently positive for enteric germs represent arguments in favor of the role of intestinal microorganisms in producing ankylosing spondylitis.
The genetic predisposition is supported by familial aggregation of cases of ankylosing spondylitis and high frequency with which is met Class I histocompatibility antigen, HLA-B27.
Ankylosing Spondylitis Pathogenesis
There are some arguments that support the role of immune mechanism:
- histological picture of inflammatory process rich in CD4 +, CD8 + lymphocytes and macrophages;
- increased levels of tumor necrosis factor ? (TNF ? );
- elevated levels of immunoglobulin A.
Two are the main morphological elements: chronic joint inflammation and peri-articular inflammation and entezitis (localized inflammation at the site of insertion of ligaments, aponeurosis and articular fascia).
- Sacral-iliac joint (sacroiliitis) is the main location of disease, being precocious affected and is characterized by the presence of subchondral granulation tissue, which leads to cartilage erosion of the iliac and sacred cartilage. Subsequently, occurs the replacement of granulation tissue with regenerative fibro-cartilage, followed by the ossification of the joint;
- The joints of the spine: first, there is an inflammatory granulation tissue, located in the insertion of the fibrous ring of inter-vertebral disc, on the edge of inter-vertebral body. The edges of the vertebral body and the peripheral region of fiber ring will be eroded and then will calcify, creating the syndesmophyte;
- Anterior inter-vertebral ligament is suffering a process of inflammation, then will appear fibrosis and finally will be calcified;
- Peripheral joints (hip, shoulder, knee) are less interested;
- The eye is affected at 20% -35% of patients with the appearance of irides inflammation and iridocilities;
- The heart: aortic valve thickening and fibrosis of excito-conductive system;
- Renal damage, more rare, it is represented by nephropathy with immunoglobulin A;
Ankylosing Spondylitis Symptoms
The onset of disease, most commonly in young men (between 20 and 40 years), is dominated by lumbosacral or buttock pain, with a character of inflammatory pain:
- Insidious onset
- Pain that appears in the second part of the night, waking up sometimes the patient from sleep;
- accompanied by morning stiffness;
- Improvement after exercise.
Sometimes back pain is radiating to the sciatic nerve path, until the popliteal space, with an alternate character.
During the status period, patients with ankylosing spondylitis present symptoms with progressive, upward character: lumbar, thoracic and cervical:
Articular manifestations of ankylosing spondylitis:
- Increased lumbosacral pain;
- Tenderness at pressing the sacroiliac joint;
- The appearance of thoracic spine pain, exacerbated by coughing or sneezing;
- Limitation of lumbar spine mobility in sagittal plan, evidenced by measuring the finger-ground index and Schober’s maneuver (in healthy individuals during maximal flexion of the spine, the distance between two points, one located at the spinous apophysis of L5 vertebra and another 10 cm above increases by more than 5 cm, while in a patient with ankylosing spondylitis, this distance increases by less than 5 cm or does not modify);
- Limitation of lateral flexion of the spine;
- reducing the mobility of the spine, put out by maneuvers: chin-sternum, occiput-wall, lateral tilt and rotation of the head.
Extra-articular manifestations in ankylosing spondylitis:
- cardiovascular impairment: aortic regurgitation. AV block;
- pulmonary fibrosis;
- inflammatory lesions of the colon;
- renal impairment: amyloidosis or immunoglobulin A nephropathy;
- neurological manifestations: horse tail syndrome.
Advanced stage is installed, usually late. The column becomes rigid, the lumbar lordosis is erased, thoracic segment of spinal cord get a cyphotic position, and the head is bent, with the eyes directed to ground.
Ankylosing Spondylitis Diagnosis
Radiological explorations are the most important for the diagnosis of ankylosing spondylitis.
Bilateral sacroiliitis is the main radiological criterion of diagnosis and has four stages:
- Stage I: discrete and wiped aspect of the joint
- Stage II: minimum sacroiliitis characterized by enlargement of the joint space, due to subchondral erosions on the both sides
- Stage III: moderate sacroiliitis, manifested by osteocondensation with decrease of joint space
- Stage IV: stiffness of the sacroiliac joint.
Vertebral radiological changes:
- the presence of the syndesmophytes (calcification of fibrous rings);
- square appearance of the the vertebrae, lumbar X-ray (due to the erosion of the anterior margins of the vertebral body);
- straightness of the lumbar spine;
Other imagistic explorations:
- computerized axial tomography, allows an early diagnosis of the articular affection, in the absence of radiological changes;
- MRI is extremely useful for viewing arahnoidiandiverticula, associated with horsetail syndrome;
- scintigraphy using technetium.
- ESR acceleration;
- increased C reactive protein;
- increased fibrinogen;
- increased alpha-2 globulin;
- increased immunoglobulin A and immune complexes;
- the absence of rheumatoid factor.
Diagnosis of ankylosing spondylitis is based on three clinical and one radiological criterion, called Van Der Linden criteria:
- Lumbar pain accompanied by stiffness, at least three months, reduced by exercise and unimproved by rest;
- Limitation of the movement of the spine in frontal and sagittal plane;
- Limitation of chest expansion.
Bilateral sacroiliitis grade II-III or unilateral sacroiliitis grade III-IV.
The presence of sacroiliitis, together with one of three clinical criteria allows diagnosis of ankylosing spondylitis.
Ankylosing Spondylitis Treatment
Treatment of ankylosing spondylitis aims to reduce inflammation, maintain spinal mobility and prevent stiffness.
Pharmacological treatment with NSAID aims to reduce inflammation, pain and paravertebral contraction:
- indometacin is the moast efficient drug, in doses of 75-100 mg / day;
- oral corticosteroids have a low efficiency in the treatment of ankylosing spondylitis. They are useful in intra-articular administration;
- in severe cases of ankylosing spondylitis : sulfasalazine, methotrexate or cyclophosphamide.
Nonpharmacological treatment is represented by: medical gymnastics, hydrotherapy and practice of sports such as swimming.
Orthopedic and surgical treatment is only recommended in debilitating forms of ankylosing spondylitis and involves performing osteotomies and arthroplasties.
Evolution and prognosis of ankylosing spondylitis:
In most cases, ankylosing spondylitis has a long evolution, with spurts of activity and remission. In severe cases with a onset in adolescence or in case of untreated ankylosing spondylitis, progression is rapid, to stiffness of several joints, giving the patient the appearance which was described in the advanced stages of ankylosing spondylitis.