Arthritis ? Flashcards
What are the different types of Arthritis ?
0 Rheumatoid Arthritis
0 Septic
0 psoriatic
0 osteoathritis
athro - joint
Iitis - inflammation
2 main types od groups
Degenerative - Osteoathritis
Inflammatory - Rheumatoid , Psoriatic , Reactive , Ankolysing Spondylitis , Juvenile inflammatory arthritis , Septic , Viral (associated with hepatitis or HIV , Para virus ,EPV) , Gout & Pseudo gout (Crystal acute arthritis ) , Arthritis associated with connective tissue diseases (CTD)
What is Psoriatic arthritis ?
What causes it ?
Psoriatic athritis
Psoriasis - autoimmune disease
Arthritis - joint inflammation
Joint inflammation that happens in people with arthritis
0 Chronic & progressive
Type of Seronegative Spondyloarthropathies
Serongative - no auto antibodies linked to them
Spondyloarthropathies- autoimmune conditions that affect joints
CAUSE
0 specific form of HLA - B27 + environmental trigger e.g trauma , infection
Have a particular form of HLA - B27 —————————> which leads to autoimmune process ———————-> self antigens seen as foreign ——————————-> T cells release cytokines stimulating inflammation ———————–> IL 23 , 1L -12 and TNF ( Tubular necrosis factor ) also released —————————-> triggers keratinocytes & fibroblasts to proliferate —————————-> Psoriatic plaque formation
mmune system attacks self antigens in joints )———————————–>
( HLA - B27 - encodes for protein MHC 1 - presents molecules from inside the cell on it surface to Cytotoxic T cells - will determine if it is self or no self )
Common symptoms of PA ?
0 Pain
0 Swelling
0 Stiffness
0 Inflammation - usually warm to the touch.
Types of PA ?
0 Oligoarticular -
o mild
o asymmetric
o affects less
than 5 joints.
0 Polyarticular / Rheumatoid pattern
o resembles RA
o symmetric
o affects more
than 5 joints
( hands, feet , wrist , ankles )
0 Spondyloarthritis,
o distal
o asymmetric
o involves spine
& sacroiliac joint
( causes fusion of vertebral bodies - causes stiffness of neck & sacroiliac joint )
0 Distal interphalangeal predominant
o affects joints at
end of fingers
and toes.
causes : nail abnormalities : o ridging o pitting Dactylitis - severe inflammation of finger and toe joint - look like sausages. -
Over time can develop severe bone erosion. - finger deformities
0 arthritis mutilans
o extensive bone erosion ——————-> deformity - opera glass hand characteristic.
Diagnosis of PA ?
Blood tests for:
o RA factor ,
o Anti
Citrullinated
protein
antibodies
( NORMALLY PRESENT IN RA but absent in Psoriatic arthritis )
X - ray show joint erosion
pencil & cup radiographic sign .
Treatment of PA ?
PAIN
0 NSAIDS
Severe cases
0 Immunomodulatory drugs
- Sulfsalazine
- Methotrexate
0 Biological response modifiers
TNF–inhibitors,
o Infliximab,
o Etanercept
o Adalimumab,
block the actions of tumor necrosis factor alpha
IL-12/IL-23 inhibitor o Ustekinumab
blocks the actions of the interleukins.
Surgery
- repair of damage hip , knee joints.
- spinal surgery - risky - rarely done.
What is Septic arthritis ?
Infectious / septic arthritis
- Arthritis caused by a microbe
- usually caused by bacteria infection in the joint .
from :
previous infection - in bone , or spread through blood.
ex - nail into knee
o synovial membrane infected by bacteria from environment or from skin surface (- shoved into knee when skin pierced)
Bacteria destroy articular cartilage with their toxins e.g enzymes that digest collagen in articular cartilage
PAMPs ———————-> immune response ————–> macrophages release IL - 1 , Tumour necrosis factor released ( pro - inflammatory molecules ) - immune cells recruited
2. Mast cells release histamine ——-> vasodilation (increased vascular permability ) ————————> more blood flow to area ——————–> joint looks red, swollen , red.
PROBLEM
0 fluid is leaking out ———–> too much ————–> increased inter -articular pressure —————–> compressed BV ————–> necrosis of affected joint & bone —————————-> joint destruction
What is Septic arthritis ?
Infectious / septic arthritis
EMERGENCY - Complete destruction of joint - rapid.
- Arthritis caused by a microbe
- usually caused by bacteria infection in the joint .
from :
previous infection - in bone , or spread through blood.
ex - nail into knee
o synovial membrane infected by bacteria from environment or from skin surface (- shoved into knee when skin pierced)
Bacteria destroy articular cartilage with their toxins e.g enzymes that digest collagen in articular cartilage
PAMPs ———————-> immune response ————–> macrophages release IL - 1 , Tumour necrosis factor released ( pro - inflammatory molecules ) - immune cells recruited
2. Mast cells release histamine ——-> vasodilation (increased vascular permability ) ————————> more blood flow to area ——————–> joint looks red, swollen , red.
PROBLEM
0 fluid is leaking out ———–> too much ————–> increased inter -articular pressure —————–> compressed BV ————–> necrosis of affected cartilage & bone —————————-> joint destruction
Types of SA ?
Symptoms of SA ?
Fever
Impaired range of motion
joint pain
(regard hot , swollen , acutely painful joint with restricted movement as septic athritis until proven otherwise)
2 types
Non - gonococcal athritis -
o usually affects 1 joint
o usually caused by S. aureus - can completely destroy joint within days.
Gonococcal athritis - less common (but more common in young adults - sexually active)
o causes - Neisseria gonorrhoeae (usually affects sexually active adolescents.)
- if Gonorrhoeae is present should refer to sexual health clinic for counselling on safe sex & testing for other sexual health disease (HIV , Chalamydia etc.)
o spreads hematogenously - from cervix , urethra , pharynx.
o multiple joints affected.
o multiple skin lesions
o Tenosynovitis - inflammation of muscle tendon.
o spread from bone if osteomyelitis present.
DIAGNOSTIC FACTORS
- Hot , swollen , painful, restricted joint
- Acute presentation - symptoms present for less than 2 weeks.
(delays in presentation can occur with TB or prosthetic infections) - Fever
- Monarticular - one joint - most common
(but some have oligoarticular / polyarticular. ) - Prosthetic joint
(always suspect if have this ) - in patients who have underlying joint pathology e.g RA , OA - look for symptoms which are disproportional to their joints - higher risk of SA - immunosuppressants , ANTI - TNF drugs (biological therapy does seem to increase risk )
Lyme athritis - bacteria from lyme disease can infect joint. - lyme disease - are diseases caught
MOST COMMON JOINTS AFFECTED
- Knee - most common
(can also effect shoulder , ankle , elbow , wrist)
RISK FACTORS
- Sexual activity
- Prostethic joint - refer to orthopedics.
- Underlying joint patholgy
- Immunosupression
- IV drug injection - either IV drug misuse of iatrogenic - (intra - articular steriod injection)
-Recent joint surgery - ## other infection
Diagnosis of SA ?
Test synovial fluid - joint aspiration
usually find ;
- looking for Gram stain (MOST IMPORTANT) -
if present (DBSAT)
o high WBC count
o positive culture
0 Blood culture (DBSAT)
Imaging
- bone erosion
- joint effusions
(Joint particularly painful - level of pain seems usual )
WBC
0 ESR
0 CRP
(however , synovial fluid analysis is more important e.g. absence of raised ESR , CRP does not exclude joint infection)
0 Urea & Electrolytes - sepsis , end organ damage
0 LFTs - used to assess for sepsis and end organ damage.
0 Plain X rays
0 Ultrasound
Treatment of SA ?
SUSPECTED/ CONFIRMED SYSTEMIC INVOLVEMENT - SEPSIS PROTOCOL
SUSPECTED/ INFECTED PROSTHETIC JOINT - refer to orthopaedics for ultrasound guided joint aspiration
antibiotics
Pain medication , consider analgesia
if CONFIRMED - refer for surgery to othropaedics.
SUSPECTED INFECTED JOINT -
inaccessible - referral to orthopaedics
accessible - empirical antibiotics + joint aspiration , consider analgesia.
CONFIRMED INFECTED JOINT - NO SYSTEMIC INVOLVEMENT
1ST LINE
0 Pathogen targeted antibiotics
(2 weeks IV unless patient shows lack of response, then start oral 4 weeks) + Joint aspiration ( relieve pressure & remove infection) , consider analgesia
- check signs of re- emergence of infection - 24hrs - 48hrs after starting oral treatment before discharging.
UNCONFIRMED INFECTION - NO SYSTEMIC INVOLVEMENT & responding to empirical antibiotics - continue + joint aspiration , consider analgesia
if not responding:
1ST LINE
- Senior clinician review + joint aspiration , consider analgesia.
(could be bcc of incorrect diagnosis , causative organism , antibiotic therapy , infection elsewhere etc.)
Athrocentesis ( joint aspiration )& wash out
Surgery - athrotomy
What is reactive arthritis ?
inflammation joint after occurrence of an infection e.g . STI , gastroenteritis .
seronegative spondyloarthropathies.
most have HLA -B27 gene - encodes for MH1
usually start 2 - 3 weeks after initial infection
tissues of the joint spaces, but occasionally, the immune system also attacks tissues like the lining of the urethra and the conjunctiva.
0 Reiter syndrome - if all 3 are affected
cevix , pericardium can be involved.
Osteoathritis vs aging
Articular cartilage
Aging
1. Water - decreased
- Less elastic (stiffness increased)
- Chondrocytes - fewer but increased size.
- Collagen - increased collagen - crosslinking / brittleness.
Osteoarthritis
- Water Increased
- More elastic - stiffness decreased.
- Chondrocytes - cells cluster 9at a late stage)
- Collagen - disorganised - increased collagenase.
What carpal bone gets fractured the most ?
Scaphoid bone - usually caused by falling on an outstretched hand.
SIGNS
0 Pain & tenderness in anatomical snuffbox. (triangular area on radial aspect of carpal bones )
proximal pole fracture - bottom 1/3rd of scaphoid bone
Distal pole fracture - top 1/3rd of the bone. (scaphoid bone has retrograde blood supply e.g BV enters wrist and supplies the bone closest to the fingers then comes back to carpal bones ————————-> distal part (top) supplied first - no direct blood supply to proximal part.
- As a result , risk of avascular necrosis to proximal part - if fracture in middle (waist) of bone.
- if scaphoid fracture is missed - likely to develop osteoarthritis in the future.
Old fashioned terms to describe problems with joint?
- just for knowledge.
Calor - heat in joint Dolor - pain Rubor - redness Tumor - swelling Rigor - stiffness Penuria / Inertia - obstruction of movement.
Main site of osteoarthritis ?
Hips - OA of the hip may cause secondary gluteal muscle weakness (positive Trendelenburg test - The unilateral leg stand orTrendelenburg testis a useful procedure for detecting hip-joint dysfunction - unable to maintain the pelvis horizontal to the floor while standing first on one foot and then on the other foot )
- also cause positive thomas test ( one knee flexed - affected side ( sacrum and lower back lift and dont remain on table/ couch) due to causing fixed flexion deformity.
knees
Pain in the knee - if your overweight or starts without any significant trauma - in one place
Primary -. age , overuse , degeneration
Secondary - caused by other conditions e.g -
- inflammatory arthritis causes damage —————> can lead to osteoathritis development in same joint.
- Gout
- Haemochromotosis - usually get arthritis in fingers if they present with osteoarthritis
- Alkaptonuria
- EDS - ehlos danros - hyper mobile joints - frequent dislocation - so damage to joint.
