Flashcards in The GALS Screen Deck (29)
Define the following terms:
Refers to definite inflammation of a joint
Refers to pain within a joint without demonstrable inflammation by physical examination
Partial dislocation of a joint
Inflammation of the synovium
Articulating surfaces are displaced and are no longer in contac
What does GALS stand for?
What is gout caused by?
It is caused by deposition of monosodium urate (MSU) crystals as a result of hyperuricaemia
What are the key clinical features of gout?
Tophi – subcutaneous depositions of aggregated monosodium urate crystals
Which joint is commonly affected by gouty arthritis?
1st Metatarsophalangeal joint – this is called podagra
List some signs of irreversible joint damage.
Loss of joint range or abnormal movement
List some signs of a mechanical defect in the joint.
Painful restriction of movement in the absence of features of inflammation
How many joints have to be involved for arthritis to be classifiedas ‘oligoarthritis’?
Describe the pattern of arthritis in the following diseases including the joints that are commonly affected and spared:
a. Rheumatoid arthritis
b. Reactive arthritis
a. Rheumatoid arthritis
Symmetrical polyarthritis involving large and small joints
Joints spared: DIP, lumbar spine, thoracic spine
Joints involved: most others
b. Reactive arthritis
Lower limb asymmetrical oligoarthritis and axial involvement
Exclusive inflammation of the 1st metatarsophalangeal joint
Joints commonly spared: axial
What is the main extra-articular feature of gout?
Tophi – subcutaneous deposits of uric acid
What are the two types of synovial lining cell?
Typa A – macrophage-like
Type B – fibroblast-like (secrete hyaluronic acid)
What is a synovial effusion?
Abnormal increase in synovial fluid volume
State two causes of spinal effusion and describe the synovial fluid composition in each of them.
Abnormal mechanical stimulation – can stimulate the fibroblasts to produce more hyaluronic acid – normal composition
Inflammation – inflammatory exudate – abnormal composition with inflammatory mediators and reduced hyaluronic acid
What features of the synovial fluid are examined to determine the cause of the synovial effusion?
How turbid it is
The presence and quantity of inflammatory cells (neutrophils in particular)
Non-inflammatory – slightly turbid – osteoarthritis or mechanical defects
Inflammatory – turbid – reactive arthritis or gout
Infection – very turbid – bacterial infection
When is synovial fluid examination performed?
When joint infection is suspected
Useful for confirming diagnosis of crystal arthritis
What are some contraindications for arthrocentesis?
Conditions that increase bleeding e.g. coagulopathy or anti-coagulant drugs
Overlying skin infection
List some possible complications of arthrocentesis
Risk of introducing infection
Bleeding into the joint
Damage to structures of the joint
What technique is used to detect crystals in the synovial fluid?
Polarising light microscopy
How is gout distinguished from pseudogout in synovial fluid examination?
Negative birefringence (polarising light microscopy)
Calcium pyrophosphate dehydrate (CPPD) crystals
What is a common feature of most connective tissue diseases?
Raynaud’s phenomenon (intermittent vasospasm of the digits on exposure to the cold)
What is Sjogren’s syndrome and what are its symptoms?
Dry eyes (xerophthalmia)
Dry mouth (xerostomia)
Parotid gland enlargement
Extra-glandular features: non-erosive arthritis + Raynaud’s
Which antibodies are associated with Sjogren’s syndrome?
What is inflammatory muscle disease and what are the two types?
Proximal muscle weakness due to autoimmune-mediated inflammation either with a rash (dermatomyositis) or without a rash (polymyositis)
Describe the skin changes that take place in dermatomyositis.
Lilac rash on eyelid, malar region and naso-labial folds
Red or purple lesions on knuckles (Gottron’s papules)
Mechanic’s hands (fissuring and cracking of the skin over the finger pads)
Which antibodies are associated with inflammatory muscle disease?
Anti-tRNA transferase antibodies
NOTE: also associated with elevated creatine phosphokinase, abnormal EMG and abnormal muscle biopsy
What other diseases is inflammatory muscle disease associated with?
Pulmonary fibrosis and Malignancy
What is systemic sclerosis?
Thickened skin with Raynaud’s phenomenon Features include:
What are the two types of systemic sclerosis and what are the differences between them?
Diffused systemic sclerosis
Fibrotic skin proximal to elbows or knees
Pulmonary fibrosis and renal involvement
SHORT history of Raynaud’s
Limited systemic sclerosis
Fibrotic skin on hands, forearms, feet, neck and face
LONG history of Raynaud’s