3 Rheumatology - Osteoarthritis + reactive Arthritis Flashcards
What is reactive arthritis?
sterile inflammation in joints (arthritis) following infection especially urogenital + gastrointestinal
(NOT DUE TO ONGOING INFECTION)
note:
- may be first manifestation of HIV or hepatitis C infection
- Symptoms follow 1-4 weeks after infection
What are important extra-articular manifestations of reactive arthritis?
- Enthesopathy
- Skin inflammation
- Eye inflammation (Sterile conjunctivitis)
ocular - Sterile Conjunctivitis
genitourinary - sterile urethritis
musculoskeletal symptoms of reactive arthritis - Arthritis (joint)
Asymmetrical
Oligoarthritis
(<5 joints)
Lower limbs typically affected
musculoskeletal symptoms of reactive arthritis - ENTHESITIS (where tendons insert)
Heel pain (Achilles tendonitis)
Swollen fingers (dactylitis) –> whole finger is inflamed
Painful feet (metatarsalgia due to plantar fasciitis)
musculoskeletal symptoms of reactive arthritis - SPONDYLITIS (spine)
Sacroiliitis (inflammation of the sacro-iliac joints)
Spondylitis (inflammation of the spine)
Compare between Rheumatoid arthritis vs Reactive arthritis
LOOK AT NOTES for comparison table
what are the different methods to diagnose reactive arthritis?
Microbiology:
- Microbial cultures (blood, throat, urine, stool, urethral, cervical)
- Serology e.g. HIV, hepatitis C
Immunology:
- Rheumatoid factor (HLA-B27)
Synovial fluid examination:
- Especially if only single joint affected
Compare between
septic arthritis vs Reactive arthritis
SEPTIC ARTHRITIS - can isolate bacterial pathogen \+ve Synovial fluid culture Antibiotic therapy = yes Joint Lavage= yes
REACTIVE ARTHRITIS
Sterile = Synovial fluid culture
Antibiotic therapy =no
Joint Lavage = no
How is Reactive Arthritis treated?
majority of patients complete resolution occurs within 2-6 months
- Articular symptoms –> give NSAIDS /intra-articular corticosteroid therapy
- extra-articular –> symptomatic treatment
- Refractory disease –> oral glucocorticoids
Generally: AVOID ANTIBIOTICS
Define Osteoarthritis
Chronic slowly progressive disorder –> due to failure of articular cartilage that typically affects joints of the hand, spine + weight-bearing joints (hips and knees)
- loss of / damage of articular cartilage
Osteoarthritis typically affects :
Joints of the hand:
- Distal interphalangeal joints (DIP)
- Proximal interphalangeal joints (PIP)
- First carpometacarpal joint (CMC)
Spine
Weight-bearing joints of lower limbs:
- esp. knees and hips
- First metatarsophalangeal joint (MTP)
Note:
Osteoarthritis can be associated with:
- Joint pain
- -> worse w activity
- Joint Crepitus
- -> creaking/ cracking sound of joint
- Joint Stability
- Joint instability
- Joint enlargement
- -> e.g heberden’s nodes
- Joint stiffness
- limitation of motion
-
What are some Radiographic features of osteoarthritis?
- Joint space narrowing
- Subchondral bony sclerosis
- Osteophytes
- Subchondral cysts
How do radiographic changes in rheumatoid arthritis vs osteoarthritis differ?
LOOK at notes for table comparison
What are causes of OA?
1) Defective and irreversible articular cartilage and damage to underlying bone due to:
- Abnormal joint components (congenital articular cartilage defect)
- Excessive loading on joints (w age/ physical activity)
2) Commonly due to lifestyle + activities + aging
3) Many factors can lead to abnormal stress or abnormal cartilage
What is synovial fluid ?
Hyaluronic acid (HA) -rich viscous fluid
viscosity = dependent on Hyaluronic acid composition
Articular cartilage consists of:
o Type II collagen
o Proteoglycan (aggrecan) –> keeps articular cartilage hydrated
o chondrocytes
note:
Articular cartilage has both Avascular and aneural structure
-
What are ECM proteoglycans?
glycoproteins containing one or more sulphated glycosaminoglycan (GAG) chains
What are GAGs ?
what are the different types of GAGs
GAGs = repeating polymers of disaccharides
different types of GAGs o Chondroitin sulphate o Heparan sulphate o Keratan sulphate o Dermatan sulphate o Heparin
What is the major proteoglycan in articular cartilage ?
aggrecan
Hyaluronic acid is the only non-sulphated GAG.
it is a major component of =
where it has a role of =
Hyaluronic acid is the only non-sulphated GAG.
it is a major component of = synovial fluid
and it has a role of = maintaining synovial fluid viscosity
What are Cartilage changes in osteoarthritis?
- reduced proteoglycan
- reduced collagen
- chondrocyte changes e.g. apoptosis
What are Bone changes in osteoarthritis?
a) Changes in denuded sub-articular bone:
- Proliferation of superficial osteoblasts –> causes production of sclerotic bone e.g. subchondral sclerosis
- Focal stress on sclerotic bone can –> focal superficial necrosis
b) Bone formation at joint margins, osteophytes e.g. ‘Heberden’s + Bouchard’s nodes
What are methods of managing osteoarthritis?
Education
Physical therapy – physiotherapy, hydrotherapy
Occupational therapy
Weight loss
Exercise
Analgesia
(Paracetamol, Non-steroidal anti-inflammatory agents, Intra-articular corticosteroid injection)
Joint replacement
What are some therapeutic approaches of managing OA?
NOT APPROVED IN UK
- Glucosamine and chondroitin sulphate
- Intra-articular injections of hyaluronic acid
- -> increases lubrication
what are
a) osteophytes
b) Heberden’s nodes
c) Bouchard’s nodes
a) osteophytes = bony outgrowths
b) Heberden’s nodes = Osteophytes at the DIP joints
c) Bouchard’s nodes = Osteophytes at the PIP joints
