SERONEGATIVE Flashcards
what is it?
This title describes a group of conditions that share certain clinical features: A predilection for axial (spinal and sacroiliac) inflammation, Asymmetrical peripheral arthritis, Absence of rheumatoid factor or ACPA antibodies, hence ‘seronegative’, Inflammation of the enthesis, A strong association with HLA-B27, but its aetiological relevance is unclear.
what are the types of seronegative arthritis
Ankylosing/ Axial spondylitis,
Psoratic arthritis,
Enteropathic (UC, Crohn’s),
Reactive arthritis.
what is Ankylosing Spondylitis?
chronic inflammatory rheumatic disorder with a predeliction for the axial skeleton/spine and the entheses. When radiographic changes at the sacroiliac joints are present, the term ‘ankylosing spondylitis’ is used. It is both more common (ratio of 5:1) and more severe in men than in women. usually early 20’s/ late teens, male who suffers increasing pain and morning stiffness in the lower back. Loss of lumbar lordosis and an increased kyphosis resulting in a question mark posture. HLA-B27 antigen association.
what is the HLA associated with this and what other diseases px with the same HLA association?
HLA-B27. Reiters, ibd, psoriasis.
what are the clincial features of AS?
Lower back pain, increasing pain and prolongued morning stiffness in the lower back and buttocks. Pain improves with exercise but not with rest. Progressive loss of spinal movement. Loss of lumbar lordosis and increased Kyphosis. There is fixed flexion of the hips and compensatory flexion of the knees. Reduced Schober test. tendersacroiliac joints. restricted lumbersacrospinal movement
What is the schober diagnostic test for AS?
Reduced spinal flexion is demonstrated by the Schober test. A mark is made at the fifth lumbar spinous process and 10 cm above, with the patient in the erect position. On bending forward, the distance should increase to > 15 cm in normal individuals.
What are the other clincial features observed?
Other features include Achilles tendinitis and plantar fasciitis (enthesitis) and tenderness around the pelvis and chest wall. Reduction in chest expansion (< 2.5 cm on deep inspiration measured at the fourth intercostal space) is due to costovertebral joint involvement.
Anterior uveitis and rarely aortic incompetence, cardiac conduction defects/ heart block and apical lung fibrosis. IBD, osteoporosis, spinal fractures, cord compression, cauda equina, AAD, secondary amyloidosis, pulmonary fibrosis, weight loss, fever, fatigue, anorexia. amyloidosis.
Ix AS
MRI whole spine
ESR and CRP often raised, HLA B27 is NOT diagnostic as it is not a specific enough test but it is used in conjunction withh clinical features and other tests.
XRAY - Bamboo Spine - erosion, calcification and sclerosis of the margins of the sacroiliac joints, proceeding to ankylosis. In the spinal column, blurring of the upper or lower vertebral rims at the thoracolumbar junction is caused by an enthesitis at the insertion of the intervertebral ligaments. This heals with new bone formation, resulting in bony spurs (syndesmophytes). Progressive calcification of the interspinous ligaments and syndesmophytes eventually produce the ‘bamboo spine’. Grading is used based on sacroiliitis.
Mx AS
physio, NSAID’s, DMARD’s (Methotrexate, Sulfasalazine), Anti-TNFalpa drugs.
What is Psoratic Arthritis?
Arthritis occurs in 10% of patients with psoriasis, particularly in those with nail disease and may precede the skin disease.
Clinical features? psoriatic arthritis
Distal interphalangeal arthritis, the most typical pattern of joint involvement – dactilytis is characteristic
Nail and skin involvement is also characterisitc
Mono- or oligoarthritis
Symmetrical seronegative polyarthritis resembling RA
Arthritis mutilans, a severe form with destruction of the small bones in the hands and feet
Sacroiliitis – unilateral or bilateral.
Ix of psoriatic arthritis
X-rays may show a ‘pencil in cup’ deformity in the interphalangeal joints
Tx of psoriatic arthritis
NSAID’s, Sulfasalazine, methotrexate, Leflunomide, Cyclosporin, anti-TNF, Anti-IL-17, Anti-IL-23
what is Reactive Arthritis?
sterile synovitis after a distal infection. Gi, urogenital or throat: Infections include- Salmonella, Shigella, Yersinia, Campylobacter, Chlamydia trachomatis or pneumoniae, Borrelia, Neisseria and streptococci.
The typical case is a young man who presents with an acute arthritis shortly (within 4 weeks) after an enteric or sexually acquired infection.
Clinical features? Reactive Arthritis
Dactylitis, skin and mucosal membrane involvement resembling Psoriasis: Keratodema blenorrhagica, circinate balantis, urethritis, conjunctivitis, iritis, Reiter’s syndrome.
