Ankylosing Spondylitis

Rheumatology

Clinicals - History

Fact Explanation
Back pain Inflammatory back pain is characteristic of ankylosing spondylitis. This is due to sacroiliitis and inflammation in the axial skeleton and subsequent damage to the spine. Later spinal stiffness develops in both sagittal and frontal planes. Stiffness lasts more than 30 minutes in the mornings. The patient may wake up in the middle of the night due to the pain and stiffness. The pain and stiffness is markedly reduced after exercise but nor after rest. Presence of this typical pain for more than three months or the stiffness with radiological evidence of ankylosing spondylitis are diagnostic. Back pain
Inflammatory back pain is characteristic of ankylosing spondylitis. This is due to sacroiliitis and inflammation in the axial skeleton and subsequent damage to the spine. Later spinal stiffness develops in both sagittal and frontal planes. Stiffness lasts more than 30 minutes in the mornings. The patient may wake up in the middle of the night due to the pain and stiffness. The pain and stiffness is markedly reduced after exercise but nor after rest. Presence of this typical pain for more than three months or the stiffness with radiological evidence of ankylosing spondylitis are diagnostic.
Peripheral arthritis Asymmetrical peripheral monoarticular or oligoarticular arthritis with predominant involvement of the lower limbs. However involvement of the hip joint is a sign of adverse prognosis. Peripheral arthritis
Asymmetrical peripheral monoarticular or oligoarticular arthritis with predominant involvement of the lower limbs. However involvement of the hip joint is a sign of adverse prognosis.
Enthesitis This is the inflammation at the insertion of bone and ligaments, tendons, or joint capsules. Patients present with pain at the above sites. This is associated with the expression of HLA-B27. Enthesitis
This is the inflammation at the insertion of bone and ligaments, tendons, or joint capsules. Patients present with pain at the above sites. This is associated with the expression of HLA-B27.
Anterior uveitis Uveitis is usually unilateral but may migrate from one eye to the other. Patients present with soreness and redness of the eye and photophobia. Anterior uveitis
Uveitis is usually unilateral but may migrate from one eye to the other. Patients present with soreness and redness of the eye and photophobia.
Psoriasis Psoriasis is a known association with ankylosing spondylitis. Patients have erythematic, plaque like silver color skin lesions, mainly over the extensor surfaces. Psoriasis
Psoriasis is a known association with ankylosing spondylitis. Patients have erythematic, plaque like silver color skin lesions, mainly over the extensor surfaces.
Inflammatory bowel disease IBD is also associated with ankylosing spondylitis. Patients present with chronic diarrhea and or abdominal pain. Inflammatory bowel disease
IBD is also associated with ankylosing spondylitis. Patients present with chronic diarrhea and or abdominal pain.
Tarsitis This is relatively common in young patients. Tarsitis
This is relatively common in young patients.
Chest pain This is due to the involvement of costovertebral joints. Chest pain
This is due to the involvement of costovertebral joints.

Clinicals - Examination

Fact Explanation
Reduced chest expansion Reduction of the chest expansion lower than the expected range is one of the diagnostic criterion for ankylosing spondylitis. This occurs in the latter stages of the disease and it is due to the chronic inflammation of the costochondral and manubrio-sternal joints. Reduced chest expansion
Reduction of the chest expansion lower than the expected range is one of the diagnostic criterion for ankylosing spondylitis. This occurs in the latter stages of the disease and it is due to the chronic inflammation of the costochondral and manubrio-sternal joints.
Tenderness at the sites of enthesitis Enthesitis causes tenderness at the sites of inflammation of tendon insertion. Tenderness at the sites of enthesitis
Enthesitis causes tenderness at the sites of inflammation of tendon insertion.
Positive Schober test The midpoint of the two posterior superior iliac spines is marked. Then the point 10cm vertically above is also marked when the patient is standing. The patient is asked to bend forward when the patient is in maximal
forward flexion, the distance between the above marked points is measured. In patients with ankylosing spondylitis the distance is less than 15cm. The limitation of the flexion is due to the syndesmophyte formation and the development of ankylosis of the lumbar vertebrae.
Positive Schober test
The midpoint of the two posterior superior iliac spines is marked. Then the point 10cm vertically above is also marked when the patient is standing. The patient is asked to bend forward when the patient is in maximal
forward flexion, the distance between the above marked points is measured. In patients with ankylosing spondylitis the distance is less than 15cm. The limitation of the flexion is due to the syndesmophyte formation and the development of ankylosis of the lumbar vertebrae.
Stooped posture The chronic inflammation of the vertebral joints causes ankylosis. Ankylosis fixes the vertebrae in the flexed position. This markedly reduces the range of movement of the spine. Stooped posture results due to long standing disease so commonly seen in elderly patients. Stooped posture
The chronic inflammation of the vertebral joints causes ankylosis. Ankylosis fixes the vertebrae in the flexed position. This markedly reduces the range of movement of the spine. Stooped posture results due to long standing disease so commonly seen in elderly patients.
Positive straight leg raising test This is due to the ankylosis of the lumbar vertebrae. Positive straight leg raising test
This is due to the ankylosis of the lumbar vertebrae.
Signs of uveitis Erythema, soreness, photophobia and constricted pupil are examination findings. Signs of uveitis
Erythema, soreness, photophobia and constricted pupil are examination findings.
Psoriatic skin lesions Psoriasis causes erythematous, silver color skin plaques. Psoriatic skin lesions
Psoriasis causes erythematous, silver color skin plaques.
Signs of aortic regurgitation These include bounding pulse, increased pulse pressure, diastolic murmur over the aortic area of the precordium and other peripheral signs of aortic regurgitation. (Eg: de Musset’s sign, Quincke’s sign, Muller’s sign) Signs of aortic regurgitation
These include bounding pulse, increased pulse pressure, diastolic murmur over the aortic area of the precordium and other peripheral signs of aortic regurgitation. (Eg: de Musset’s sign, Quincke’s sign, Muller’s sign)
Features of cauda equina syndrome Patients present with bladder, bowel, or sexual dysfunction with saddle back anesthesia. Features of cauda equina syndrome
Patients present with bladder, bowel, or sexual dysfunction with saddle back anesthesia.

Investigations - Diagnosis

Fact Explanation
X-ray Osteo-proliferation presence of syndesmophytes and ankylosis decreased bone density are radiological features. In the latter part of the illness pathological fractures can be seen. Presence of bilateral sacroiliitis of grade two or more or unilateral sacroiliitis of grade 3—4 are radiological diagnostic criteria. Presence of radiological evidence and one clinical condition is diagnostic. X-ray
Osteo-proliferation presence of syndesmophytes and ankylosis decreased bone density are radiological features. In the latter part of the illness pathological fractures can be seen. Presence of bilateral sacroiliitis of grade two or more or unilateral sacroiliitis of grade 3—4 are radiological diagnostic criteria. Presence of radiological evidence and one clinical condition is diagnostic.
MRI This enables the early detection of the disease, well before the sacroilitis is evident in the X-ray film. MRI
This enables the early detection of the disease, well before the sacroilitis is evident in the X-ray film.
Computer tomography (CT) CT is able to detect the chronic sacroilitis. Computer tomography (CT)
CT is able to detect the chronic sacroilitis.
C-reactive protein (CRP) Raised due to the inflammatory process. However only about half of the patients will have raises CRP. C-reactive protein (CRP)
Raised due to the inflammatory process. However only about half of the patients will have raises CRP.
MHC class I molecule The presence of this molecule is more predictive of the disease than the HLA-B27. MHC class I molecule
The presence of this molecule is more predictive of the disease than the HLA-B27.
HLA B27 Presence of HLA-B27 is associated with increased risk of cardiac complications. HLA B27
Presence of HLA-B27 is associated with increased risk of cardiac complications.
Erythrocyte Sedimentation Rate (ESR) Raised due to inflammation. This has limited use in the diagnosis. Erythrocyte Sedimentation Rate (ESR)
Raised due to inflammation. This has limited use in the diagnosis.

Investigations - Management

Fact Explanation
X-ray This is useful and more sensitive in detecting the structural progression of the chronic disease than the MRI. X-ray
This is useful and more sensitive in detecting the structural progression of the chronic disease than the MRI.
Magnetic resonance imaging (MRI) This detects even mild improvement in inflammation and is the investigation of choice in follow up of the patients who are taking antiTNF (Tumor Necrosis Factor) therapy. Magnetic resonance imaging (MRI)
This detects even mild improvement in inflammation and is the investigation of choice in follow up of the patients who are taking antiTNF (Tumor Necrosis Factor) therapy.
Ultrasonography This detects the associated joint complications like enthesitis and synovitis better than the MRI. Ultrasonography
This detects the associated joint complications like enthesitis and synovitis better than the MRI.
Computer tomography (CT) CT is able to detect the chronic sacroilitis. However since the risk of radiation is high this is not practiced routinely. Computer tomography (CT)
CT is able to detect the chronic sacroilitis. However since the risk of radiation is high this is not practiced routinely.
Echocardiogram Detects aortic root involvement. Aortitis and aortic regurgitation are possible complications. Echocardiogram
Detects aortic root involvement. Aortitis and aortic regurgitation are possible complications.
ECG Detects conduction abnormalities ECG
Detects conduction abnormalities
MRI Able to detect the early disease. Also used on screening of asymptomatic patients. MRI
Able to detect the early disease. Also used on screening of asymptomatic patients.

Management - Supportive

Fact Explanation
Education Education about the disease and the treatment options is essential. Education
Education about the disease and the treatment options is essential.
Psychological support This is a chronic and debilitating disease. Younger the age at the time of diagnosis severe the disease course and results in worse functional status. Psychological support
This is a chronic and debilitating disease. Younger the age at the time of diagnosis severe the disease course and results in worse functional status.
Exercise Limits the stiffness and improves the functional outcome. Exercise
Limits the stiffness and improves the functional outcome.
Spa treatment This is considered a better option than the self-monitored exercise programs. Spa treatment
This is considered a better option than the self-monitored exercise programs.
Corrective surgery of aortic regurgitation Aortic valve replacement is the preferred treatment method of aortic regurgitation. Corrective surgery of aortic regurgitation
Aortic valve replacement is the preferred treatment method of aortic regurgitation.
Treatment of cardiac complications Management of conduction disturbances may need pacemaker implantation. Treatment of cardiac complications
Management of conduction disturbances may need pacemaker implantation.

Management - Specific

Fact Explanation
Non-steroidal anti-inflammatory agents These drugs inhibit the synthesis of prostaglandin E2 and reduce the inflammatory process. Both non-selective, non-steroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 inhibitors are used in the treatment. NSAIDs have shown to arrest the radiological progression of the disease, and the osteophyte formation. Poor response to NSAIDs is recognized an indicator of poor prognosis of the disease. Non-steroidal anti-inflammatory agents
These drugs inhibit the synthesis of prostaglandin E2 and reduce the inflammatory process. Both non-selective, non-steroidal anti-inflammatory drugs (NSAIDs) and selective COX-2 inhibitors are used in the treatment. NSAIDs have shown to arrest the radiological progression of the disease, and the osteophyte formation. Poor response to NSAIDs is recognized an indicator of poor prognosis of the disease.
Disease-modifying antirheumatic drugs (DMARDs) Generally DMARDs are not much effective in the treatment of the ankylosing spondylitis. However sulfasalazine is proven to improve peripheral arthritis, but there is no significant improvement in back pain. Leflunomide is proven to improve peripheral arthritis. Disease-modifying antirheumatic drugs (DMARDs)
Generally DMARDs are not much effective in the treatment of the ankylosing spondylitis. However sulfasalazine is proven to improve peripheral arthritis, but there is no significant improvement in back pain. Leflunomide is proven to improve peripheral arthritis.
Physiotherapy Improves the functional status of the patient. Physiotherapy
Improves the functional status of the patient.
Tumor necrosis factor blockers Infliximab is the commonly used drug in this group. Tumor necrosis factor blockers
Infliximab is the commonly used drug in this group.
Joint replacement surgery When the hip joint damage adversely affects the mobility of the patient joint replacement surgery is an option. Joint replacement surgery
When the hip joint damage adversely affects the mobility of the patient joint replacement surgery is an option.

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