rheumatology Flashcards
what markers can measure the rate of collagen formation in the blood
P1NP and P1CP
what is cathepsin k
enzyme which breaks down collagen; secreted by osteoclasts
what type of collagen are bones, ligaments, tendons, and skin made of
type 1
what does type 4 collagen make
the basement membrane
what does type 10 collagen make
the growth plate
what are the different areas of the bone
epiphysis, metaphysis, diaphysis
woven vs lamellar bone
woven bone is made quickly and is disorganised
lamellar bone is made slowly and it is more organised. lamellar bone is remodelled woven bone.
what are osteons
cylinders of lamellae which contain the blood and nerve supply in the centre in a canal called the harversian canal
what is the difference between the type of bone in the epiphysis and the diaphysis
the epiphysis has trabecular bone and the diaphysis has cortical bone
where do osteoblasts originate from
mesenchymal stem cell
what is the function of alkaline phosphatase (ALP) in bone and why do you measure it in the blood
Alkaline phosphatase is produced by osteoblasts. It facilitates the deposition of minerals (mainly calcium and phosphate) in the bone matrix. The enzyme helps with bone formation and remodelling.
Measuring alkaline phosphatase levels in the blood can be a diagnostic tool to assess bone health. Elevated levels of alkaline phosphatase may indicate increased bone turnover, as seen in conditions such as bone growth (during periods of rapid bone growth, like adolescence) or in diseases that affect bone metabolism, such as Paget’s disease, osteomalacia, or certain bone tumors.
why do you get hyperexcitability in hypocalcaemia
Calcium contributes to setting the threshold for action potentials because calcium maintains a constant background gradient and the action potential is triggered by entry of sodium into the cell. When calcium levels are low, the threshold may be altered, making it easier for nerve cells to reach the threshold and generate action potentials.
where in the nephron is most calcium reabsorbed
in the proximal convoluted tube
FGF-23 function and what is it produced by
regulates Vit D levels. FGF-23 decreases Vit D to decrease phosphate gut absorption and also increases renal phosphate excretion
it is secreted by osteocytes
if you have a low calcium diet will you absorb less calcium?
no. you will synthesise more Vit D3 (calcitriol) so that you can absorb more Ca from your diet
effect of PTH on serum phosphate levels
decreases serum phosphate levels –> more excretion of phosphate in DCT
what is osteoid
unmineralised bone tissue which is secreted by osteoblasts and needs to become mineralised
interstitial vs appositional growth and why is it relevant
interstitial –> from within –> growth in length
appositional –> from the outside –> growth in width
bones grow like this so that they don’t increase in weight. they are broken down from within by osteoclasts whilst they are being built from the outside by osteoblasts
what is the process of how bones are built
formation of cartilage model from hyaline cartilage by chondroblasts
you get primary ossification in diaphysis and secondary ossification in epiphysis
ossification slowly starts replacing cartilage
fusion of growth plates marks end of growth
how does cartilage get its nutrients
diffusion
what is the ossification of the growth plate called
endochondral ossification
what is the ossification of the bones of the skull called
intramembranous ossification
why is exercise physiologically good for bone
the stress form exercise downregulates osteoclast activity –> less chance of osteoporosis
what are the red flags for bone cancer
bone pain (worse at night)
pathological fracture
soft tissue swelling
type 1 vs type 2 muscle fibres
type 1 - slow twitch fatigue resistant
type 2a - fast twitch fatigue resistant
type 2b - fast twitch fatigue sensitive (largest fibres and strongest contractions)
how do muscles sense stretch and tension
stretch: muscle spindles
tension: intrafusal muscle fibres which are wrapped around gamma nerve fibres
what is the storage form of calcium in bone
calcium hydroxyapatite
what protects the tendons from overstretching and explain the pathophysio
the Golgi tendon organ
when the muscle contracts the tendon stretches –> if the golgi tendon organ senses too much stretch it sends impulse to 1 beta neurons in spinal chord. this synapses on an interneuron which then stimulates the alpha neuron innervating the muscle, causing muscle relaxation and preventing muscle damage
what type of collagen is cartilage made from
type 2 collagen
what is uric acid synthesised from
the breakdown of purines
why does alcohol increase the chance of gout
alcohol increases purine synthesis and decreases the excretion of uric acid
explain how osteoblasts and osteoclasts communicate to remodel bone
osteoBlast expresses RANKL which binds to osteoClast RANK receptor. This activates osteoClasts.
osteoBlasts also form OPG (osteoproteginin) which downregulates RANKL to control osteoclast activation
so if you have more RANKL than OPG you get bone resorption and if you have less RANKL than OPG you have decreased bone resorption
sclerostin is secreted by osteoclasts to STOP bone formation by binding to the WNT receptor on osteoblasts
what is Desonumab
medication which stops RANKL production so stops osteoclast formation
what is rhomosozumab
medication which inhibits sclerostin to promote bone formation
what is the most common cause of ricket’s
vit d deficiency
what is septic arthritis
infection of 1 or more joints due to pathogens
what is the most common cause of septic arthritis
staph aureus
risk factors for septic arthritis
pre-existing joint disease, intravenous drug user, joint prosthesis, immunosuppression, alcohol abuse, diabetes, recent joint surgery, intra-articular corticosteroid injection
key presentations of septic arthritis
acutely hot swollen painful red joint
onset less than 2 weeks
fever
reduced motion
lethargy
sepsis: tachycardia, hypotension, cold, clammy, shaking
1st line and gold standard investigations for septic arthritis
1st line: blood culture, CRP/ESR, FBC: raised WCC
gold standard: urgent aspirate joint for MC+S
management of septic arthritis
aspirate joint
empirical antibiotic
after lab results come you change antibiotic to the strain of bacteria identified
NSAIDS for analgesia
if patient is already on steroids stop them if possible
what antibiotics do you give for septic arthritis caused by N. gonorrhoea
IM ceftriaxone + azithromycin
what is osteomyelitis
Inflammatory condition of bone and bone marrow caused by an infectious organism, most commonly staph aureus.
most common cause of osteomyelitis
staph aureus
risk factors for osteomyelitis
Previous osteomyelitis, penetrating injury, IVDU, diabetes (diabetic foot ulcers), HIV, recent surgery, infection, sickle cell, rheumatoid arthritis, chronic kidney disease, children (upper respiratory tract or varicella infection)
what is acute osteomyelitis and what are possible complications
Inflammation and Bone Edema → In the early stages of bone infection, there is an acute inflammatory response. The affected bone becomes inflamed, and there is an accumulation of immune cells and fluid, leading to bone edema
complications: chronic osteomyelitis, formation of sequestra and invlucurum
key presentations of osteomyelitis
limping, reluctance to bear weight, hot, erythema and swollen joint, dull pain, bone oedema , muscle aches
what representative feature of acute osteomyelitis should you see on an MRI
bone oedema
what representative feature of chronic osteomyelitis should you see on an MRI? explain what they are
Sequestra: areas of necrotic (dead) bone, known as sequestra, may form. These are surrounded by inflammatory tissue and pus.
Involucrum: formations of new bone around sequestra to compensate for lack of support from necrotic bone. This new bone, called involucrum, is thickened and sclerotic, serving as a protective shell.
investigations for osteomyelitis
1st line - raised WCC, CRP, ESR, blood culture, X-ray, MRI
gold standard - bone marrow biopsy and culture
what is charcot’s foot
Charcot’s foot / neuropathic arthropathy - Complication from peripheral neuropathy from diabetes.
You get progressive degeneration of the weight bearing joints of the foot due to loss of innervation which causes loss of sensation so even if you have damage to your foot you don’t feel it and this results in repetitive minor traumas to the foot → Arthropathy
All of the repetitive damage leads to chronic inflammation in the foot → you get arch collapse → structural failure of foot and ankle → foot more susceptible to soft tissue breakdown and infection
Signs: red, hot, swollen foot
management of osteomyelitis
immobilise and give antibiotics
supportive therapy
surgical removal of necrotic bone
give examples of some inflammatory connective tissue disorders
lupus, scleroderma, sjogren’s syndrome
risk factors to lupus
female (14-40)
drugs - isoniazid
HLA link
EBV
smoking
genetics
pathophysiology of lupus
In a normal person apoptosed cells should be cleared out by the immune system but if they are not cleared out then the cellular contents, including the DNA are exposed to the immune system → the immune system mounts an attack against our own proteins and nuclear material
The antibodies to a person’s nucleus are called ANA (Antinuclear Antibodies) and when they bind to the surface antigen of a cell or they form complexes which deposit in tissues and they can cause different kinds of inflammation.
Some people with lupus are also deficient of complement system proteins like C3 and C4 → apoptosis can’t happen well
When the body’s immune system autoregulation kicks in the body can slowly recover → that is why you get flare ups
Anything that causes mass cell apoptosis can trigger flare-ups:
UV light
Surgery
Infection
Pregnancy
Stress
key presentations of lupus
Face
Photosensitive (eyes)
Red malar butterfly rash
Neurological
Cognitive impairment
Seizures
Psychosis
Delirium
Peripheral neuropathies
Lungs
Pulmonary fibrosis
Pulmonary vasculitis
Pleural effusion
Cardiovascular
Pericarditis
Pericardial effusion
Myositis
Valvular disease
Hypertension → complication of nephritic syndrome
GI
Splenomegaly
Kidney
Nephritic syndrome
MSK
Arthralgia
Arthritis
Raynaud’s phenomenon → episodic cyanosis of fingers due to vasoconstriction from the cold or emotional stress
Osteopenia and osteoporosis → due to low Vit D from low sun exposure, renal osteodystrophy, long term use of steroids, age, female sex (menopause)
Non-specific symptoms
Fever
myalgia/fatigue
Hair loss
Weight loss
Mouth ulcers
Lymphadenopathy → swollen lymph nodes
Chronic anaemia
Leucopenia
1st line and gold standard investigations for lupus
FBC (anaemia, leukopenia, thrombocytopenia)
CRP, ESR → indicate inflammation but are not always high; for example when you are stable and are not having a flare-up
Kidney function → urinalysis, raised urea and creatinine, urine albumin:creatinine ratio (proteinuria), urine dipstick (haematuria, proteinuria)
LFTs
renal USS for pyelonephritis
Gold standard
Antibodies
anti-nuclear (ANA)
anti-double-stranded DNA (aDsDNA)
Complement system proteins → low complement levels C3, C4
what antibodies do you test for in lupus
anti-nuclear (ANA)
anti-double-stranded DNA (aDsDNA)
management of lupus
1st line – Hydroxychloroquine
Consider: NSAIDs (for the MSK pain), corticosteroid, immunosuppressant (methotrexate), monoclonal antibodies (rituximab)
Others: treat anaemia and reduce cardiovascular risk by decreasing hypertension
what is scleroderma and what are the types
Systemic sclerosis in which normal tissue is replaced with thick dense connective tissue. It affects skin, blood vessels and internal organs. 2 types: limited cutaneous systemic sclerosis (CREST syndrome) and diffuse cutaneous systemic sclerosis.
what is the cause of scleroderma
Autoimmune antibodies attacking connective tissue
risk factors for scleroderma
Women 30-50yo, family history, exposure to environmental substances and toxins (silica dust, solvents)
key presentations of scleroderma
CREST mnemonic
Calcinosis (calcified nodules under skin),
Raynaud’s phenomenon
Esophageal dysmotility (strictures, food gets stuck on swallowing),
Sclerodactyly (tightening and thickening of skin over fingers distal to MCP joint),
Telangiectasia (prominent dilated capillaries, especially on cheeks)
what is raynaud’s phenomenon
episodic cyanosis of fingers due to vasoconstriction from the cold or emotional stress
what is sclerodactyly and what disease is it associated with
tightening and thickening of skin over fingers distal to MCP joint
associated with scleroderma
what is Telangiectasia and what disease is it associated with
prominent dilated capillaries, especially on cheeks
associated with scleroderma
what are complications of scleroderma
Coronary artery disease, pulmonary hypertension, pulmonary fibrosis, GORD, kidney failure, malabsorption, hypothyroidism
gold standard investigations for scleroderma
Anti centromere antibodies (limited/CREST)
Anti-SCL70 (diffuse)
what is Sjogren’s syndrome
autoimmune condition affecting exocrine glands and causing dry mucous membranes
what other diseases can have Sjogren’s syndrome as a complication
lupus with rheumatoid arthritis
key presentations of Sjogren’s syndrome
Dry mucous membranes – dry mouth (xerostomia), dry eyes (keratoconjunctivitis sicca), dry vagina
gold standard investigations for Sjorgen’s syndrome
Anti-Ro and anti-La antibodies
management of Sjorgen’s syndrome
1st line – artificial tears, artificial saliva, vaginal lubricant.
Hydroxychloroquine used to halt progression
dermatomyositis vs polymyositis
dermatomyositis = connective tissue disorder with inflammation of muscles and skin
polymyositis = chronic inflammation of muscles
key presentations of dermatomyositis and polymyositis
SYMMETRICAL wasting of muscles of shoulder and pelvic girdle and muscle pain, fatigue and weakness
in dermatomyositis only you get
gottron lesions (scaly erythematous patches) on knuckles, elbows, and knees. Purple rash on face and eyelids. Photosensitive erythematous rash on back, shoulders and neck. Periorbital oedema. Subcutaneous calcinosis
1st line and gold standard investigations for dermatomyositis and polymyositis
1st line (think about muscle damage markers)
Lactate dehydrogenase raised → cellular damage
AST and ALT raised → AST found everywhere, in liver and in muscles and kidneys
myoglobin raised → only found in muscle after muscle injury
creatinine kinase raised (>1000 U/L. Normal = <300.) → also shows muscle injury but not as accurate because it can be influenced by muscle mass; waste product produced after metabolism of creatine phosphate in muscle
Serology: anti-Jo-1 (polymyositis), anti Mi2 (dermatomyositis), anti-nuclear antibodies (dermatomyositis). Electromyograph
gold standard
muscle fibre biopsy
management of dermatomyositis and polymyositis
1st - steroid
2nd - immunosuppressant
3rd - monoclonal antibody
1st line – prednisolone. Also, IV immunoglobulin
2nd line – immunosuppressant (methotrexate, azathioprine)
3rd line – rituximab or cyclophosphamide
osteoarthritis definition
Degenerative joint disorder, not inflammatory. Osteoarthritis is ‘wear and tear’ of synovial joints, resulting from mechanical and biological events that destabilise the normal degradation and synthesis of cartilage.
risk factors to osteoarthritis
High intensity labour, old age, women, obesity, occupation/sports, genetic
pathophysiology of osteoarthritis
Due to wear and tear over time there is more cartilage breakdown than repair causing an imbalance. Chondrocytes respond by metalloproteinase secretion which degrades type 2 collagen and causes cysts. Bone underneath cartilage attempts to overcome this response by producing more type 1 collagen which leads to abnormal bony growths (osteophytes) and cysts
what are the most commonly affected joints in osteoarthritis
hips, knees, distal interphalangeal joints, thumb, cervical spine, sacroiliac joints
key presentations of osteoarthritis
Transient painful joints stiff for <30 mins in morning, worse throughout day. Proximal Bouchard nodes and distal Heberden nodes on fingers.
Hard asymmetrical bulky non-inflamed joint, squaring at the base of thumb (carpometacarpal saddle joint)
Bouchard nodes vs Heberden nodes
signs for osteoarthritis; they are bulky non-inflamed joints
B –> proximal
H –> distal
gold standard investigation for osteoarthritis
x-ray
what x-ray changes do you see in osteoarthritis
L - loss of space between bones
O - osteophytes
S - subchondral sclerosis
S - subchondral cysts
management of osteoarthritis
1st line - lifestyle (less weight-bearing, physio), topical analgesics (capsaicin, NSAIDs – diclofenac, methyl salicylate), + paracetamol, + opioid (PPI for gastric protection)
joint replacement surgery (arthroplasty)
what is reactive arthritis
synovitis in a joint as a result of a recent infective trigger
Typically causes monoarticular synovitis → affects single joint in lower limb (mc knee).
how do you distinguish between reactive arthritis and septic arthritis?
in reactive arthritis there is NO JOINT INFECTION
what is Reiter syndrome
reactive arthritis
what are the causes of reactive arthritis
STIs or gastroenteritis
Chlamydia trachomatis → most common
N. gonorrhoeae → although it usually causes septic arthritis not reactive arthritis
Gastroenteritis: campylobacter jejuni, salmonella enteritidis, shigella
what are risk factors to reactive arthritis
HLA B27 gene → this gene is known for seronegative spondyloarthropathy
Male
preceding STI or gastroenteritis
key presentation of reactive arthritis
Can’t See –> conjunctivitis
Can’t pee –> urethritis/balanitis (dermatitis of the head of the penis)
Can’t climb a tree –> arthritis
onset 1-4 weeks after infection
what is balanitis
dermatitis of the head of the penis
investigations for reactive arthritis
ESR and CRP raised → indicate presence of inflammation
Negative ANA (antinuclear antibodies) → rule out lupus
Rheumatoid factor negative → rules out rheumatoid arthritis
X-ray to identify structural changes to joints
sacroiliitis - inflammation of the sacroiliac joints
enthesopathy - disorder of the enthesis of bones (the enthesis connects tendon to bone)
joint aspiration negative → exclude septic arthritis and gout
stool cultures → to rule out GI infections
urine dipstick → to exclude UTI
Polarised light microscopy → rule out crystal arthropathy
management of reactive arthritis
you ALWAYS assume septic arthritis until proven otherwise so first line you give antibiotics and do joint aspiration
once septic arthritis is ruled out you give
NSAIDs (naproxen, ibuprofen, indometacin)
intra-articular corticosteroid injection
DMARDs - disease-modifying anti-rheumatic drug (sulfasalazine)
or
TNF inhibitors in chronic arthritis
rheumatoid arthritis
Autoimmune condition causing inflammation of the synovial lining of joints, tendon sheaths and bursa. Inflammatory symmetrical polyarthritis
what is the population that has rheumatoid arthritis like
Women 30-50 (3x more likely than men premenopausal)
causes of rheumatoid arthritis
Autoimmune, genetic (HLA DR4/DR1)
pathophysiology of rheumatoid arthritis
autoimmune destruction of synovium via the autoantibody RHEUMATOID FACTOR which attacks IgG antibodies. This causes inflammation and damage to tendons, bones, cartilage and ligaments
Cyclic citrullinated peptide antibodies (anti-CCP) are autoantibodies which also target healthy joint tissues.
key presentations of rheumatoid arthritis
Joint pain worse in morning (>30mins) gets better as day goes on and with movement
Symmetrical distal Polyarthropathy
hot inflamed joints most common in wrist/hand + feet, knee, hip.
signs of rheumatoid arthritis
Swan neck thumb
ulnar deviation
boutonniere deformity
Z shaped thumb deformity; DIP joint often spared.
make sure that you can picture all of these words in your head
investigations for rheumatoid arthritis
Serology: anti CCP positive, rheumatoid factor positive!!!!!
Bloods: anaemia, CRP/ESR raised
x-ray: less lost joint space, erosion, soft tissue swelling, soft bones
management of rheumatoid arthritis
1st line – DMARDs (disease modifying anti-rheumatic drugs) e.g., methotrexate, leflunomide, sulfasalazine
2nd – Add biological agent
Infliximab → monoclonal antibody against TNF-a
Adalimumab → TNF inhibitor
Etanercept → TNF-a inhibitor (all of the TNF inhibitors prevent TNF from triggering inflammation)
Rituximab → monoclonal antibody that targets B cells
3rd – corticosteroid (prednisolone), NSAIDs (ibuprofen)
Pregnant: prednisolone, sulfasalazine, hydroxychloroquine
pseudogout vs gout
pseudogout caused by formation of calcium pyrophosphate crystals as a result of direct injury whilst gout is caused by high blood uric acid levels which leads to monosodium urate crystal deposits in joints
pseudogout more common in females over 70 and gout more common in middle aged overweight men
risk factors for pseudogout
Females over 70
hyperthyroidism
hyperparathyroidism
excess iron or calcium
diabetes
metabolic diseases
mainly think about diseases which affect calcium metabolism –> they are the primary risk factors cuz in pseudogout you get CALCIUM pyrophosphate crystals
1st line and gold standard investigations for pseudogout
1st line
X ray and elevated serum calcium, iron and PTH
gold standard
joint aspiration and polarised light microscopy (rhomboid shaped crystals, positive birefringent of polarised light, calcium pyrophosphate crystals)
what feature do you see on an x-ray of pseudogout
CHONDROCALCINOSIS
thin white line in the middle of joint space caused by calcium deposition
management of pseudogout
1st line – NSAIDs, colchicine, corticosteroids/intra-articular steroid injection
what is colchicine
antinflammatory med used specifically for gout
risk factors for gout
high purine diet (meat, seafood, beer)
increased cell turnover → more uric acid production so more needed to be excreted
CKD → can’t excrete uric acid efficiently
Diuretics; especially thiazide diuretics → diuretics can compete with uric acid for excretion + dehydration causes the ECM to be more concentrated → higher chance for uric acid to form crystals
what oxidises purines to uric acid
xanthine oxidase
pseudogout and gout: are the polyarticular or monoarticular
pseudogout: poly
gout: mono
what are the most common locations of gout
often big toe/DIPs/wrist/thumb
what are tophi
subcutaneous deposits of uric acid affecting small joints and connective tissue in DIPs, elbow, ears
sign of gout
make sure that you can picture them
1srt line and gold standard investigation for gout
1st line
serum uric acid levels
gold standard
joint aspiration and polarised light microscopy (needle-like crystals, negative birefringent of polarised light, monosodium urate crystals)
what characteristics do you see in polarised light microscopy in pseudogout vs gout
Pseudogout
- rhomboid shaped crystals
- positive birefringent of polarised light
- calcium pyrophosphate crystals
Gout
- needle-like crystals
- negative birefringent of polarised light
- monosodium urate crystals
what changes do you see on a gout x-ray
maintained joint space
Punch out lytic lesions
Overhanging sclerotic borders
soft tissue tophi
management of gout
Lifestyle changes (decreased purines, more diary – antigout)
Acute flare: NSAIDs, Colchicine, corticosteroids
Prevention: allopurinol (xanthine oxidase inhibitor > reduces uric acid)
what is allopurinol
xanthine oxidase inhibitor > reduces uric acid
prevention medication for gout
which types of arthritis manifested as night pain and morning pain
night pain - gout
morning pain - rheumatoid
which are the seronegative spondyloarthropathies
ankylosing spondylitis, reactive arthritis and psoriatic arthritis
what is ankylosing spondylitis
Inflammatory condition mainly affecting sacroiliac joints and vertebral column and causing progressive stiffness and pain.
what gene is highly associated with ankylosing spondylitis
HLA B27
pathophysiology of anchylosing spondylitis
inflammation of spine and rib cage leads to formation of new bone and fusion of joints
syndesmophytes replace spinal bone –> spine less mobile
syndesmophyte vs osteophyte
Syndesmophytes are paravertebral ossifications which bridge across the joint
osteophytes are located at the margin of a degenerative synovial joint and are non-bridging
key presentations of anchylosing spondylitis
Progressively worse and chronic lower back pain and stiffness
worse with rest and improves with movement
Worse at morning and night
Sacroiliac pain
Flares of worsening symptoms.
what is lumbar lordosis
the natural inward curve of the lower back
signs of anchylosing spondylitis
Anterior uveitis, dactylitis, enthesitis
lumbar pathology: decreased lumbar lordosis > more kyphosis
Schober test shows decreased lumbar flexion <20cm
what is the Schober test and how do you do it
used to assess decrease in lumbar spine range of motion (flexion) due to ankylosing spondylitis
Patient is standing, examiner marks the L5 spinous process by drawing a horizontal line across the patient’s back.
A second line is marked 10 cm above the first line.
Patient is then instructed to flex forward as if attempting to touch his/her toes, examiner remeasures distance between two lines with patient fully flexed.
The difference between the measurements in erect and flexion positions indicates the outcome of the lumbar flexion
if the schober test indicates lumber flexion of less than 20 cm –> ankylosing spondylitis
1st line and gold standard investigations for anchylosing spondylitis
1st line
CRP and ESR raised, HLA B27 genetic test, MRI spine (bone marrow oedema in early disease before x-ray changes)
gold standard
x-ray of spine and sacrum
what is an early MRI sign of anchylosing spondylitis
bone marrow oedema
what x-ray changes do you see in anchylosing spondylitis
Bamboo spine (fusion of vertebral bodies)
· Sacroiliitis
· Squaring of vertebral bodies
· Subchondral sclerosis and erosions
· Syndesmophytes (bony outgrowths in spinal ligament)
· Ossification of ligaments, discs and joints
· Fusion of facet, sacroiliac and costovertebral joints
management of ankylosing spondylitis
1st line – NSAIDs (naproxen, indomethacin, ibuprofen)
Steroids during flares
anti-TNF drugs e.g., etanercept.
Monoclonal antibodies against TNF (infliximab)
physiotherapy and lifestyle advice
surgery for deformities
what conditions is HLA B27 mutation associated with
anchylosing spondylitis, psoriatic arthritis, reactive arthritis, IBD,
what disorders is HLA DR3-DR4 mutation associated with
lupus
rheumatoid arthritis
type 1 diabetes
coeliac disease
what is psoriatic arthritis
inflammatory arthritis associated with psoriasis –> red scaly rash
key presentations of psoriatic arthritis
Inflammatory joint pain
plaques of psoriasis (hidden – behind ears, under nails, scalp)
onycholysis (separation of nail from nail bed)
dactylitis (inflammation of finger)
enthesitis (tendon/ligament insertion inflammation)
Nail pitting
general key presentations of spondyloarthropathies
SPINE ACHE mnemonic
Sausage digits (dactylitis)
Psoriasis → red scaly patches
Inflammatory back pain
NSAIDs > good response
Enthesitis (tendon/ligament insertion)
Arthritis
Crohn’s/colitis/CRP raised → chron’s has the HLA B27 component
HLA B27
Eye (uveitis/conjunctivitis)
1st line and gold standard investigations for psoriatic arthritis
1st line
CRP/ESR raised, rheumatoid factor -ve, anti-CCG negative, joint aspiration negative for crystals or bacteria
gold standard
joint x-ray
x-ray changes in psoriatic arthritis
erosion in distal interphalangeal joint and periarticular new bone formation.
· Osteolysis.
· Pencil-in-cup deformity (central erosions of bone beside the joints causing one to look hollow like a cup, and one to sit in the cup)
· Periostitis (periosteum inflammation causing thickened, irregular outline of bone)
· Ankylosis (joints fuse causing stiffness)
· Dactylitis (finger inflammation appears as soft tissue swelling)
what does seronegative stand for in seronegative spondyloarthropathies
-ve for serum rheumatoid factor which is the autoantibody which causes rheumatoid arthritis
what other inflammatory conditions in the body are associated with psoriatic arthritis
Anterior uveitis, conjunctivitis, aortitis (inflammation of the aorta), amyloidosis (amyloid = abnormal protein → you get abnormal protein deposits on organs)
what is the most severe complication of psoriatic arthritis
arthritis mutilans
caused by osteolysis which leads to shortening of bones on fingers
how do you manage psoriatic arthritis
1st line – NSAIDs for pain (naproxen, ibuprofen, indomethacin), intra-articular corticosteroid injection if severe
DMARDs (methotrexate, sulfasalazine, leflunomide), TNF inhibitor or monoclonal Ab (etanercept, adalimumab, infliximab), last resort – ustekinumab (Mab targeting IL 12 and 23
what class of medications are the meds which finish in MAB like infliximab and adalimumab and rituximab
monoclonal antibodies which inhibit TNF
what are DMARDs and give an example
disease modifying anti-rheumatic drugs
methotrexate pt sulfasalazine
what is etanercept
a TNF blocker
what does a bamboo spine of the X-ray indicate
ankylosing spondylitis
osteopenia vs osteoporosis
osteopenia = low bone mineral density unrelated to malnutrition or nutrient deficiency
osteoporosis = more severe decrease in bone mineral density
causes of osteoporosis
50+ postmenopausal Caucasian women
SHATTERED mnemonic
steroids
hyperparathyroidism and hyperthyroidism
alcohol
thin (low BMI)
low testosterone
early menopause
renal/liver failure
erosive/inflammatory bone disease
key features of osteoporosis
Fractures (proximal femur, colles wrist fracture → fracture of the radius, compression vertebral crush - kyphosis)
1st line and gold standard investigations for osteoporosis
1st line
FRAX score (10-year probability of major osteoporotic fracture or hip fracture), Calcium, phosphate, ALP normal
gold standard
DEXA bone scan - T score (normal = T > -1, osteopenia = -2.5 < T < -1, osteoporosis = T < -2.5)
why would ALP be normal in osteoporosis
in osteoporosis bone formation stays the same and bone resorption increases. ALP only used in bone formation so it won’t change + ALP is not a specific marker for osteoporosis; it is also in bile and liver
what is the FRAX score
The FRAX score estimates the 10-year risk of major osteoporotic fracture, including the risk of fracturing the spine, hip, forearm, or shoulder
management of osteoporosis
Lifestyle – exercise, weight, low alcohol and smoking. Vitamin D and calcium supplementation.
1st line –Bisphosphonates (reduce osteoclast activity), e.g., alendronate, risendronate, zoledronic acid.
2nd line – denosumab (monoclonal antibody which binds to RANK-ligand and blocks osteoclast)
Hormone replacement therapy, raloxifene (stimulates oestrogen bone receptor)
osteomalacia vs rickets
Poor bone mineralisation leading to soft bone due to lack of Ca2+ in ADULTS
Rickets: inadequate mineralisation of the bone and epiphyseal cartilage in the growing skeleton of CHILDREN
key presentations of osteomalacia and rickets
Osteomalacia: bone pain and tenderness. Dull ache, worse on weight-bearing exercises. Fractures (esp neck of femur), muscle weakness (waddling gait, difficulty with stairs)
Rickets: growth retardation, hypotonia, knock-kneed, bow-legged
1st line and gold standard treatment for osteomalacia + management
1st line
X-ray (loss of cortical bone – defective mineralisation, looser zone), U&E (low calcium and phosphate), raised PTH, low serum 25-hydroxyvitamin D (<25 nmol/L = deficiency)
gold standard
bone biopsy (incomplete mineralisation)
Managemnet –> Vit D supplements (cholecalciferol) + calcium supplements
what is giant cell arteritis
Vasculitis is a group of diseases causing inflammation of blood vessels. Giant cell arteritis affects large blood vessels
Autoimmune attacking of blood vessels
risk factors for giant cell arteritis
Over 50 y.o, northern European, females, Hx of polymyalgia rheumatica
FOR THIS CONDITION THE RISK FACTORS ARE VERY IMPORTANT
what part of the arterial system is generally affected by giant cell arteritis
aorta and/or its major branches
THINK CAROTID, TEMPORAL ARTERIES AND OCCIPITAL ARTEIRES
key presentations of giant cell arteritis
Headache (new onset, unilateral over temporal area), scalp tenderness (hurts to brush hair), jaw claudication, visual disturbances (blurred, diplopia, amaurosis fugax – transient vision loss, blindness), thickened temporal arteries and weak pulses
what is amaurosis fugax
transient vision loss, blindness
1st line and gold standard investigations for giant cell arteritis
1st line
Raised CRP, Raised ESR >50mm/hr (ESR IMPORTANT IN THIS DISEASE). FBC (anaemia), LFT/RFT may be abnormal
Halo sign (wall thickening) on vascular ultrasonography of temporal and axillary artery
gold standard
Temporal artery biopsy (shows giant cells, granulomatous inflammation – patchy lesions therefore take big sample)
management of giant cell arteritis
Pain in temporal region in an elderly woman is GIANT CELL ARTERITIS until proven otherwise → steroids stat otherwise she loses her vision
1st line – high dose STEROIDS (e.g., prednisolone 40-60mg)
Consider: tocilizumab, methotrexate. Amaurosis fugax – high dose IV methylprednisolone.
what disease is giant cell arteritis highly associated with
POLYMYALGIA RHEUMATICA
what is polymyalgia rheumatica
Inflammatory condition causing pain and stiffness in shoulders, pelvic girdle, and neck.
risk factors for polymyalgia rheumatica
Females, white, always 50+, associated with giant cell arteritis
key presentations of polymyalgia rheumatica
Features should be present for at least 2 weeks to make diagnosis
Bilateral shoulder pain radiating to elbow
Bilateral pelvic girdle pain
Pain worse with movement and causes insomnia
morning stiffness >45 mins
rapid response to corticosteroids
DDx of polymyalgia rheumatica
Fibromyalgia
Osteoarthritis
rheumatoid arthritis
SLE
Myositis
Cervical spondylosis
management of polymyalgia rheumatica
steroid –> prednisolone
