MSK Flashcards
What is the pathophysiology of rheumatoid arthritis?
Infiltration of synovium by inflammatory cells. Angiogenesis, means that synovium then grows over the cartilage, forming a pannus. This destroys the bone and cartilage, leading to bony erosions. Autoimmune condition
What condition are pannus and bony erosions seen?
RA
What are key features of RA? (clinical presentation)
- stiffness worse in the morning, lasts more than an hour
- decreased grip strength
- Symmetrical
- Subcutaneous nodules
- Ocular involvement
- no DIP involvement (end of finger)
- more acute development
What is the typical patient affected by rheumatoid arthritis?
Female, middle age, FHx, other AI conditions
What auto antibody is seen in rheumatoid arthritis?
Anti CCP (very specific). Also RF: less specific
what is seen on a xray for RA?
loss of joint spacy, erosions, soft tissue swelling, soft bones (osteopenia)
What is the treatment for RA?
- DMARDs: inhibit the action of cytokines and lymphocytes. Eg, methotrexate, sulfasalazine
- NSAIDs
- biological agents: eg, anti-TNF
- steroid injections
What is the pathphysiology of osteoarthritis?
loss of cartilage with bone remodelling and inflammation. Progressive destruction.
What condition are osteophytes seen?
osteoarthritis. Due to bony regrowths calcifing
What is the clinical presentation of OA?
- slow development
- stiffness decreases after an hour in the morning
- worse at night
- exacerbated by exercise
- reduced functioning
- bony swelling: bouchards (PIP) nodes and heberdens nodes (DIP)
- asymmetric
What condition are Heberdens and Bouchards nodes seen in?
OA
What is the dx of OA?
- normal CRP, no RF, no CCP
- xray: LOSS. Osteophytes
What is the tx for OA?
pain relief, exercise, weight loss. Eventually joint replacement
What 5 things are seen in sero-negative arthritis?
Seronegative spondyloarthopathies share five main traits: Predilection for axial inflammation, Asymmetrical peripheral arthritis, Absence of rheumatoid factor, Inflammation of the enthesis and a Strong association with HLA-B27
What are the sero-neg conditions
ankolysing spondylitis, reactive arthritis, psoriatic arthritis
what is the enthesis?
connective tissue between tendon/ligament and bone
What are severe forms of psoriatic arthritis?
dactylitis (pencil in a cup deformity) and mutilans (destructive form)
What is the clinical picture of psoriatic arthritis?
Large range from mild synovitis to severe progressive arthroplasty.
Usually preceded with a rash.
Nail changes
Can present similarly RA. Assymetrical large joints and spine
What % of patients with psoriasis develop psoriatic arthritis?
20%
What is seen in diagnosis of all sero neg arthritis?
- negative for anti-CCP and RF
- raised CRP and ESR
What is the tx for psoriatic arthritis?
- DMARDs, NSAIDs, TNF-alpha inhibitors (inflixamib)
- surgery to connect destroyed/deformed joints
What is spondyloarthritis?
inflammatory disorder of the spine. Ankolysing occurs by forming syndesmophytes (bony growth in ligaments). This fuses the spine
What lymphocytes are involved in spondyloarthritis?
CDT8
What is the presentation of spondyloarthritis?
Progressive loss of spine movement. Increasing pain and morning stiffness, which improves with exercise. Often, lower back and buttocks. Swollen knee due to inflammatory effusion. Asymmetrical.
Loss of lumbar lordosis
What group of people is ankylosing spondyloarthritis typically seen in?
Young males
What is the gold standard dx for ankylosing spondylitis, and what is seen?
- MRI picks up more
- detects inflammation and oedema
- shows erosion and sclerosis
- bamboo spine
What is reactive arthritis?
- persistent bacterial antigen in the synovium joints. Drives inflammation
When does reactive arthritis occur after infection?
2-4 weeks
What is Reiter’s triad and what condition does it relate to?
Reactive arthritis: can’t see, can’t pee, can’t climb a tree (conjunctivitis, urethritis, arthritis)
What organisms commonly cause Reactive arthritis?
- STD: chlamydia
- GI: campylobacter, salmonella, shigella
What is the dx for reactive arthritis?
- stool culture
- sexual hx
- aspirate: exclude septic arthritis/gout
What is septic arthritis?
active infection response. Direct injury/blood borne infection can cause inflammation and loss of joint function
What is the presentation of septic arthritis?
Single, swollen joint on movement. Swollen and tender, generally monoarthritis
What is the most common cause of septic arthritis?
S.aureus infection.
Gram negative more common in older people
What is dx for septic arthritis?
- raised CRP
- raised neutrophils
- joint aspirate: turbid, yellow
What is the tx for septic arthritis;
drain the joint. Empirical antibiotics: flucoxacillin.
What is systemic lupus erythematous?
inflammatory, multisystem autoimmune disease with ANA
What is the most specific antibody for SLE, and what is used to track development?
- anti double stranded DNA antibody: most specific
- ESR: used to track development
- ANA also present but non specific
What are some key clinical presentations of SLE?
- general: fatigue, malaise, raynauds
- arthralgia: symmetrical joint and muscle pain
- photosensitive, butterful rash (triggered by UV light)
- pulmonary involvement
- cardiovascular involvement
- renal involvement: haematuria, HTN
- neuro: various psychiatric manifestations
What level of hypersensitivity reaction is SLE?
Type III
What is the pathophysiology of SLE?
apoptotic cells and fragments inefficiently cleared by phagocytes. Transferred to lymphoid tissue, and auto antibodies produced against self cells. Clinical manifestations due to antibody formation, development and deposition of immune complexes, complement activation
What is the tx for lupus?
- NSAIDs and corticosteroids for arthralgia
- immunosuppression for severe symptoms (rutiximab)
What is dermamyositosis?
polymyositis with skin involvement
What is Sjogren’s syndrome?
lymphocytic infiltration of exocrine glands. Chronic inflammatory disease.
What is the clinical presentation of Sjorgren’s syndrome?
dry eyes, dry mouth, enlargement of the parotid gland. Vaginal dryness, dry cough, dysphagia
What is Schirmer’s test diagnostic for?
Sjogren’s. this is when you see if the eye rehydrates. If tears roll less than 10mm = significant
What auto antibodies are present in Sjogren’s?
The antibodies associated with Sjogren’s include anti-Ro and anti-La antibodies, rheumatoid factor, and antinuclear antibodies.
What is antiphospholipid syndrome, and its pathophysiology?
Hypercoaguable state due to ALP-antibodies. These activate complement and produce antibodies against coagulation factors, activate platelets and vascular endothelium
What is the clinical presentation of anti phospholipid syndrome?
- coagulation problems
- livedo reticularis (mottled discolouration of the skin)
- Obstetric problems (eg, recurrent miscarriages)
- thrombocytopenia (affects renal, cerebral and other vessels)
What is the treatment for APL syndrome?
acute thrombolysis management
what is polymyositis? What is the pathophysiology?
Autoimmune inflammation and necrosis of skeletal muscle fibres. Mediated by cyto-toxic T cells and autoimmune factors.
What is the clinical presentation of polymyositis?
Symmetrical progressive muscle weakness and wasting; affects proximal shoulder muscle and pelvis girdle (difficulty raising arms and going up stairs). Raynauds. Can involve dysphagia and dysphonia
What is the dx and tx of polymyositis?
- dx: muscle biopsy: increased ALT and ALP
- Tx: oral prednisolone
What is Raynaud’s? How is it treated?
Abnormalities of blood vessel wall that common occurs with autoimmune conditions. Treatment via calcium channel blockers
How does gout present on microscopy?
- needle shaped
- negative birefringent on polarised light