Rheumatology Flashcards
Which type of macrophages reside within the synovium?
Type A synoviocytes
Which cells produce hyaluronic acid within the synovium?
Fibroblast-like cells (Type B)
Which extracellular matrix protein is prevalent within the synovial fluid?
Hyaluronic acid
Which proteoglycan predominates within the articular cartilage?
Aggrecan
Name an example of degenerative arthritis?
Osteoarthritis
What is inflammation?
Inflammation is a physiological process in response to alleviate injury or infection. An excessive/inappropriate inflammatory reaction can be deleterious to the host
What are the 5 features of inflammation?
Red (Rubor) Pain (Dolor) Hot (Calor) Swelling (Tumour) Loss of function (Functio Laesio)
In response to an infection/injury what role doe pro-inflammatory mediators and cytokines have?
Increase vascular flow and inflammatory cell recruitment in tissue
Which cytokines are released during inflammation?
• TNF-alpha, IL-I, IL-6, IL-17.
What type of crystals form in gout?
urate crystals
What is gout?
Gout is a syndrome characterised by hyperuricaemia and deposition of urate crystals - Acute flares of inflammatory arthritis.
• Tophi around the joints and potential joint destruction
• Affects the first toe (podagra), foot, ankle, knee, fingers, wrist and elbow.
What are the manifestations of gout?
Tophi around the joints and potential joint destruction
Affects the first toe (Podagra), foot, ankle, knee, fingers, wrist and elbow
What is podagra?
Gout affecting the first toe
Which type of foods result in an increased risk in developing gout?
Purine rich foods
What are the three main causes for gout?
Genetic tendency Increased intake of purine rich foods Reduced excretion (Kidney failure)
How do gout crystals triggers an acute inflammatory response?
Interact with undifferentiated phagocytes within the joint, releasing TNF-alpha and iL-8 (Neutrophil chemoattractant)
Which chemoattractant molecule is responsible for the recruitment of neutrophils in gout?
IL-8 causing neutrophilic synovitis
Which immune cell is associated with gout synotivits?
neutrophil
What are the symptoms of gout?
• Rapid onset severe pain (10+ severity)
• Joint stiffness
• Joint red, warm, swollen and tender
• Tophi – Aggregated deposits of urate monosodium urate crystals
• Foot joint distribution (Metatarsophalangeal joint)
• Swelling and joint effusion
• Gouty arthritis
N.B: Resolves spontaneously over 3-10 days.
How severe is gout pain?
10+ severity
What are tophi?
Aggregated deposits of urate monosodium urate crystals
How quickly does gout resolve?
Resolves spontaneously within 3-10 days.
Which crystals are associated with psuedogout?
Calcium pyrophosphate crystals within the joint space
What are the risk factors for developing pseudogiout?
Background osteoarthritis
Elderly patients
intercurrent infection
What types of erosions are seen in patients with pseduogout?
Rat bite erosions
What are the first line investigations for gout?
Arthrocentesis with synovial fluid analysis (joint aspiration)
What WBC is expected in patients with gout?
WBC > 2 x 10^9/L
How are crystals detected in gout?
Polarising light microscopy to detect crystals
What happens to synovial fluid samples?
Examined for patients - rapid gram stain followed by culture and antibiotic sensitivity assays
What shaped crystals are gout?
Needle shaped
What shaped crystals are found in pseudogout?
brick-shaped
What are the birefringence of gout crystals?
Negative
What are the birefringence of pseudogout crystals?
Positive
What is rheumatoid arthritis?
Rheumatoid arthritis is a chronic autoimmune condition that manifests as pain, stiffness, and symmetrical synovitis (inflammation of the synovial membrane) of synovial (diarthrodial) joints.
• Inflamed synovial membrane
• Increased angiogenesis (neovascularisation)
• Cellular hyperplasia
• Influx of inflammatory cells (Activated B & T cells, plasma cells, mast cells and activated macrophages) Invade the synovial lining.
Which cytokines are prevalent within rheumatoid arthritis?
TNF-alpha
IL-1
IL-6
What is the function of the synovial membrane?
To include the maintenance of the synovial fluid, the hyaluronate rich viscous fluid within the joint soace