Connective Tissue And Joint Diseases Flashcards
What is SLE?
- Systemic lupus erythematosus is an autoimmune disorder leading to inflammation and tissue damage in multiple organ system.
- It involves autoantibody production, deposition of immune complexes, complement activation, and accompanying tissue destruction/vasculitis.
- Associated with HLA-DR2 and HLA-DR3.
What are the clinical features associated with neonatal lupus?
- Skin lesions
- Cardiac abnormalities such as AV block and transposition of the great vessels
- Valvular and septal defects
What are the 11 diagnostic criteria of SLE?
MD SOAP BRAIN
- Malar rash (butterfly rash)
- Discoid rash
- Serositis
- Oral or nasal ulcers
- Arthritis
- Photosenisitivity
- Blood
- Renal
- ANA antibody positive
- Immune antibodies (Anti-ds DNA, Anti-Smith, Antiphospholipid, Antihistone, Ro (SS-A) and La (SS-B))
- Neurological
What is the diagnostic criteria for SLE?
Patient musta have at least 4 criteria (at least 1 clinical criteria and 1 immunologic criteria) OR biopsy proven lupus nephritis with a positive ANA or anti-dsDNA.
How is SLE managed?
- Avoid sun exposure
- NSAIDs for less severe symptoms
- Corticosteroids for acute flares
- Hydroxychloroquine for long term therapy, but baseline and annual eye examination as it causes retinal toxicity
- Cyclophosphamide for active glomerulonephritis
Which conditions are ANA positive?
- SLE
- RA
- Scleroderma
- Sjogren syndrome
- Mixed connective tissue disease
- Polymyositis and dermatomyositis
- Drug-induced lupus (antihistone Abs is more sensitive and specific, kidneys and CNS are not affected)
What are the most common causes of death in SLE?
Opportunistic infections and renal failure. So, renal function should be monitored and treated.
What is scleroderma?
- AKA systemic sclerosis, it is a chronic connective tissue disorder that can lead to widespread fibrosis involving multiple organs.
- Cytokines stimulate fibroblasts, causing an abnormal amount of collagen deposition so, it is the high quantity of collagen that causes the problems associated with this disease.
- It has 2 types: limited and diffuse
What are the facial features of scleroderma?
- Microstomia
- Lip retraction
- Beaked nose
- Perioral furrows
How is scleroderma diagnosed?
- ANA positive in almost all patients
- Anticentromere antibody is very specific for limited form
- Antitopoiomerase I antibody is very specific for diffuse form
What is Sjögren syndrome?
- A multi organ autoimmune disease characterized by lymphocytes infiltrate and destroy the lacrimal and salivary gland.
- Associated with HLA-DR3
What are the clinical features of Sjögren syndrome?
- Dry eyes
- Dry mouth and tooth decay
- Arthralgias, arthritis, fatigue
- interstitial nephritis and vasculitis
How is Sjögren syndrome diagnosed?
- ANA
- Ro (SS-A) and La (SS-B)
- Schirmer test: normal is >15 mm in 5 minutes
- Salivary gland biopsy most accurate but not needed for diagnosis
What is Rheumatoid Arthritis?
- A chronic inflammatory autoimmune disease involving synovium of joints and inflammation of synovium can cause damage to cartilage and bone.
- Associated with HLA-DR4
What are the characteristic features of joint involvement?
- Symmetrical, loss of mobility of >3 joints
- Can involve every joint except DIP joints, commonly involves PIP, MCP and wrists
- Morning stiffness lasting >1 hour
- Ulnar deviation of MCP joint
- Boutonnière deformities of PIP (flexed PIP, hyperextended DIP)
- Swan-neck contractures of the fingers (flexed MCP, hyperextended PIP, flexed DIP)
- C1-C2 subluxation and instability, so cervical spine radiographs should be taken prior to surgery to avoid complication during intubation