Introduction to rheumatology Flashcards
What is connective tissue?
- Binds together, supports and strengthens other body tissues
- Protects and insulates internal organs
- Compartmentalises structures such as skeletal muscle
- The major transport system within the body
- Site of stored energy reserves
- Main site of immune responses
What are the 3 classes of connective tissue?
- Cells
- Fibres
- Ground substance
What are the cells in connective tissue?
1- Fibroblast 2 - Macrophage 3 - Mast Cell 4 - Plasma Cell 5 - Lymphocytes 6 - Leukocytes 7 - Adipose Cell
What are the different types of fibres in connective tissue?
- Reticular
- Elastic
- Collagen
What are the different types of ground substance in connective tissue?
- Macromolecules
- Multi-adhesive glycoproteins
Does connective tissue have a nerve supply?
Yes (except cartilage)
Does connective tissue occur on free tissue?
No
Are connective tissue vascular?
Yes highly vascular (except cartilage and tendons)
Where is the ground substance?
Between the cells and fibers
What is the function of the matrix ground substance?
•Between the cells and fibers •Supports cells •Binds them together •Provides a medium through which substances are exchanged. Ex. Hyaluronic Acid
What are collagen fibres?
- Strong, resist forces, flexible
* Made of collagen (most abundant protein in the body)
What are elastic fibres?
- Smaller in diameter than collagen fibres
- Branch to form network
- Made of protein elastin
What are reticular fibres?
- Provide support for the walls of blood vessels
* Made of collagen with a glycoprotein covering
Describe fibroblasts
- Large flat cells with branching processes.
- Migrate throughout connective tissue secreting the fibres and ground substance
Describe macrophages
- Develop from white blood cells.
- Surround and engulf material by phagocytosis
Describe mast cells
- Alongside blood vessels that supply connective tissue.
- Produce histamine – a chemical that dilates blood vessels.
Describe adipocytes
- “Fat cells”
- Store triglycerides
What is the most abundant protein in the body?
Collagen
What are the different types of connective tissue?
- Tissue proper: loose/ dense
- Cartilage:hyaline/elastic/fibrocatilage
- Bone tissue: spongy/compact
- Blood
What are the different types of loose connective tissue proper?
- Areolar
- Adipose
- Reticular
What are different types of dense connective tissue proper?
- Regular
- Irregular
- Elastic
What is the function of connective tissue proper?
- Binding tissue
* Resists mechanical stress esp. tension
What are the cells in connective tissue proper?
- Fibroblasts
- Fibrocytes
- Defense cells
- Fat cells
What is the matrix in connective tissue proper
- Gel like ground substance
* Collagen, reticular and elastic collage
Does cartilage have vascular and nerve supply?
Cartilage is AVASCULAR and NO nerve supply (but the perichondrium does)
What is the function of cartilage?
- Strengthen and supports connective tissue
- Resists compression
- Cushions and support body structures
What are the cells in cartilage?
- Chondroblasts – in growing cartilage
* Chondrocytes
What is the matrix in cartilage?
- Gel-like ground substance
* Fibres: collagen, elastic fibres in some
Describe hyaline cartilage
- Gel like ground substance
- Most abundant cartilage in the body
- End of long bones to cushion joints and at epiphyseal plates
- Weakest of the 3 types of cartilage
Describe fibrocartilage
- Chondrocytes scattered among visible bundles of collagen fibers
- No perichondrium
- Strongest of the 3 types of cartilage
- Found in the intervertebral discs
Describe elastic cartilage
- Chondrocytes located in a threadlike network of elastic fibers
- Provides strength, elasticity and maintains the shape of certain structures (like the external ear)
What is the function of bone tissue?
- Resists compression and tension
* Protect and support
What are the cells in bone tissue?
- Osteoblasts
- Osteocytes
What is the matrix in bone tissue like?
- Gel-like ground substance
- Calcified with inorganic salts
- Fibers: Collagen
What is compact bone tissue like?
- Osteon: basic unit of compact bone
- Lamellae: concentric circles of matrix
- Lacunae: spaces in the matrix that house cells
- Osteocytes: mature bone cells
What is spongy bone tissue like?
-Trabeculae: column of bone with spaces filled with red bone marrow
What is the function of blood as a connective tissue?
•Transport O2, CO2, nutrients, wastes and other substance
What are the cells in blood as a connective tissue?
- Erythrocytes (RBC) – Transport O2
- Leukocytes (WBC) – Function in immunity
- Platelets – Blood Clotting
What is in the matrix of blood as a connective tissue?
- Liquid
- Plasma
- No fibers
What is rheumatoid arthritis?
- autoimmune disorder primarily affecting joints resulting in warm swollen painful joints
- Symptoms are typically worse following rest.
What is systemic lupus erythematosus(SLE)?
- autoimmune disorder of connective tissues
- Affects multiple organ systems and joints.
What is vasculitis?
is a group of disorders that destroy blood vessels by inflammation
What are the macroscopic changes in rheumatoid arthritis?
synovitis, bone, cartilage, erosion and angiogenesis diagram
What are the microscopic changes in rheumatoid arthritis?
cells, IL, ANF, synoviocytes, osteoclasts, proteases, CD4 cells, plasma cells, neutrophils
How long do symptoms of rheumatoid arthritis last?
- Greater than 6 weeks
- Often lasts long
What is inflammatory synovitis in rheumatoid arthritis?
- Palpable synovial swelling
* Morning stiffness > 1 hour, fatigue
Where do the symptoms of rheumatoid arthritis come up?
Symmetrical and polyarticular (> 3 joints)
•Typically involves wrists, MCP, and PIP joints
•Typically spares certain joints
Thoracolumbar spine
DIPs of the fingers and IPs of the toe
What is the difference between the osteoarthritis and rheumatoid arthritis?
- RA: inflammatory / autoantibodies / small joints / 30-50
- OA: degenerative / no antibodies / large weight bearing joints / >60
What happens in rheumatoid arthritis?
- Bone erosion
- Swollen inflamed synovial membrane
- Cartilage wears away
- Reduced joint spaced
What happens mircroscopically in RA?
- Cytokines: TNF alpha, IL - 6 IL -17
- Cartilage destruction: MMPs, NO
- Bone destruction RANKL
How do people present?
-Joint pain
-Swelling
-Stiffness
(affects small joints)
-Stiffness in morning (evening:+ osteoporosis
-Symmetrical
What are the critical elements of a treatment plan for RA?
- Assess current activity
- Morning stiffness, synovitis, fatigue, ESR
- Document the degree of damage
- ROM and deformities
- Joint space narrowing and erosions on x-ray
- Functional status
- Document extra-articular manifestations
- Nodules, pulmonary fibrosis, vasculitis
- Assess prior Rx responses and side effects
What is finger PIP swelling in rheumatoid arthritis?
- Swelling is confined to the area of the joint capsule
* Synovial thickening feels like a firm sponge
What are some of signs in RA?
- May have nodules: subcutaneous or periosteal at pressure points
- Rheumatoid factor
- 45% positive in first 6 months
- 85% positive with established disease
- Not specific for RA, high titer early is a bad sign
- Marginal erosions and joint space narrowing on x-ray
What are some of signs during RA?
- May have nodules: subcutaneous or periosteal at pressure points
- Rheumatoid factor
- 45% positive in first 6 months
- 85% positive with established disease
- Not specific for RA, high titer early is a bad sign
- Marginal erosions and joint space narrowing on x-ray
What is the typical course for RA?
•Damage occurs early in most patients
•50% show joint space narrowing or erosions in the first 2 years
•By 10 years, 50% of young working patients are disabled
•Lower life expectancy
•Multiple causes
•Compared to general population
Women 10 years less, men 4 years less
How is education important in treatment of RA?
- Build a cooperative long-term relationship
- Use materials from the Arthritis Foundation and the ACR
- Assistive devices
How is exercise important in treatment of RA?
•ROM, conditioning, and strengthening exercises
How are medications important in treatment of RA?
- Analgesic and/or anti-inflammatory
- Immunosuppressive, cytotoxic, and biologic
- Balance efficacy and safety with activity
How are NSAIDs used in RA?
- Symptomatic relief, improved function
* No change in disease progression
How are Low-dose prednisone used in RA?
Low-dose prednisone (£10 mg QD)
•May substitute for NSAID
•Used as bridge therapy
•If used long term, consider prophylactic treatment for osteoporosis
How are intraarticular steroids used in RA?
Intra-articular steroids
•Useful for flares
What are the key X-ray changes found in RA?
- Loss of joint space
- Juxta-articular bone erosions
- Soft-tisue swelling
- Osteopenia
- Sublaxtions
What are some other treatment options for RA with DMARDs?
-Disease modifying drugs (DMARDs) •Minocycline Modest effect, may work best early •Sulfasalazine, hydroxychloroquine Moderate effect, low cost •Intramuscular gold Slow onset, decreases progression, rare remission Requires close monitoring
What are some other treatment options for RA with immunosuppressive drugs?
Immunosuppressive drugs •Methotrexate Most effective single DMARD Good benefit-to-risk ratio •Azathioprine Slow onset, reasonably effective •Cyclophosphamide Effective for vasculitis, less so for arthritis •Cyclosporine Superior to placebo, renal toxicity
What are some new DMARDs?
-Leflunomide
•Pyrimidine inhibitor
•Effect and side effects similar to those of MTX
-Etanercept
•Soluble TNF receptor, blocks
TNF
•Rapid onset, quite effective in refractory patients in short-term trials and in combination with
MTX
•Injection site reactions, long-term effects unknown, expensive
How do you monitor the treatment of with DMARds?
- These drugs need frequent monitoring
- Blood, liver, lung, and kidney are frequent sites of adverse effects
- Interval of laboratory testing varies with the drug
- 4- to 8-week intervals are commonly needed
- Most patients need to be seen 3 to 6 times a year
What are some of the other extraarticular manifestations in RA?
Liver Cardiovascular Neurological Musculoskeletal Bone Marrow Spleen
What happens in SLE?
- Alopecia
- Malar rash
- arthralgia
- Oral ulcers
- Photosensitivty
What happens in scleroderma?
- reflux
- raynauds’s
- digital
- ulcerations
