Pathology Flashcards
Describe connective tissue diseases
Autoimmune conditions - autoantibodies present
Starts an inflammatory process leading to symptoms
May be associated with hypersensitivity
Affects 1-2% of the population
How do connective tissue diseases present
Often with MSK symptoms
Many also come with systemic symptoms
What is rheumatoid arthritis
Inflammation of the joint caused by rheumatoid factor and an autoantibody against Fc IgG
What happens in the acute phase of RA
Pannus formation - granular tissue forms on articular surfaces
Hyperplastic and reactive synovium
How is cartilage affected by RA
It is destroyed by the inflammatory process
This leads to a loss of joint space
What happens in chronic phase of RA
Fibrosis occurs
This can lead to joint deformity
What is SLE
Systemic Lupus Erythema
A systemic autoimmune condition
What is the cause of SLE
Autoantibodies are formed that attack the structural parts of DNA
Most specific is anti-double stranded DNA but may be other types (anti-RO etc)
What are the acute features of SLE
Oedema
Fibrin
Reactive features in the synovial cells
How is uric acid formed in the body
The end product of purine synthesis
So formed in the production of adenine and guanine - during DNA synthesis
What can lead to increased production of uric acid
Idiopathic - unknown enzyme defect Know defect - LN syndrome Increased cell turnover - e.g. psoriasis or cancer Alcohol High dietary purine - red meat etc
What can cause reduced excretion of uric acid
Drug side effects
Common with thiazide diuretics
Hypothyroidism
Chronic renal impairment
What causes gout
Precipitation of urate crystals, usually in joints
This elicits an acute inflammatory response leading to symptoms
What is gouty tophus
Deposition of urate crystals in the soft tissues
The presentation of gout is dependant on the level of urate in the body - true or false
False
Not necessarily related to level, more dependant on the solubility of the crystals
What are some complications of gout
Can cause secondary degenerative changes in the joint
Deposition in soft tissues (gouty tophus)
Can lead to renal disease
How would you diagnose gout
Take an aspirate of joint fluid and examine under a cross polarized light to look for the negatively bifrigent needle shaped crystals
Can also look for raised inflammatory markers and serum uric acid - not specific enough
Link to renal impairment - kidney tests
What causes pseudogout
Deposition of calcium pyrophosphate crystals in the joint
May be associated with hypercalcemia, haemochromatosis, hyperthyroidism etc
Age also contributes
Where does pseudogout usually affect
older individuals
in the large joints
Affects fibrocartilage
What are the symptoms of pseudogout
May present with joint pain
Usually asymptomatic and is an incidental finding on x-ray
Will have raise in inflammatory markers
what do calcium pyrophosphate crystals look like
Rhomboid shaped
Thicker and bigger than urate
What is Paget’s disease of bone
Caused by abnormality of bone turnover
Increase in osteoclastic activity
Get more bone but not normally structured - often weaker but thicker
Can affect all bones
What can cause Paget’s
Unknown
May have genetic component
Can be caused by viral infection
How does Paget’s present
Pain - due to fracture or nerve compression
Enlargement of bones leading to abnormal shape
Increased metabolism – heat in area
What are some complications of Paget’s
Heart failure - due to high metabolic requirement
Increased risk of malignancy
What is Osteomalacia
Abnormal vitamin D metabolism
Bones become weaker
Causes rickets in children
What LFT results may suggest Paget’s
Raised Alk Phos
Everything else normal
What can a pathological fracture be a sign of
Underlying bone pathology
Osteoporosis is most common cause
Potentially malignancy
What is a pathological fracture
When a fracture occurs with a non-severe trauma
So injury is out of proportion with event
Describe the initial phases of bone repair after a break
Haematoma – fibrin mesh
Influx of inflammatory cells
Cytokine release
After 1 week a callus forms and remodelling begins
How does bone heal after the initial phase
Woven bone starts to be deposited next to the cortical bone
Some cartilage is deposited at the break site which later undergoes ossification
Woven bone is remodelled to return bone to normal
Why might healing of a bone be delayed
Poor blood supply and poor nutrition.
Too much movement, Too great a distance
Which cancers commonly metastasise to bone
Lung
Kidney
Breast
Prostate
What is avascular necrosis
Infarction of bone
Leads to necrosis of tissue
How does avascular necrosis present
Usually asymptomatic
May lead to hip replacement once joint is severely damaged
What can cause avascular necrosis
Trauma Alcohol Steroid injections Sickle cell Infection
What can cause degenerative diseases like osteoarthritis
Mechanical injury
Wear and tear with age
Secondary to previous joint issues
What joint changes occur in degenerative disease
Small cracks in cartilage
Fibrillation
Cartilage is completely worn away and surface of bone becomes polished
Cysts form in the bone due to leaking synovial fluid
Bone remodelling leads to abnormal outgrowths - osteophytes
What genetic investigation can be used to diagnose MSK lesions
Karyotyping - gives overview of chromosome structure
– good for large, more obvious mutations
FISH - detects more subtle, specific mutations
- used for known translocations
How does immunohistochemistry work
You place a pigment or florescent tag onto an antibody for a specific protein
If the protein is present in the cell type it will show up
What are ganglion cysts
Caused by degenerative change within connective tissue
Presents as a lump that does not go away
In peripheral areas, near a joint capsule or tendon sheath
Common on wrist
Ganglion cysts are not true cysts - true or false
True
The do not have an epithelial lining
What are superficial fibromatoses
Due to proliferation of fibroconnective tissue
Common condition
Occurs in the hand, feet and penis (rarely)
What is dupuytren’s contracture associated with
Alcohol
Anticonvulsants
What is Dupuytren’s contracture
Superficial fibromatosis in the hand
Caused one finger to become drawn to palm - excess tissue tightens
Usually idiopathic
What is deep fibromatosis
Deep seated fibromatosis that occurs in more visceral areas
Often in the mesentery or pelvis
Comes with increased risk of colon cancer as associated with FAP
What are the different types of Giant cell tumour
Pigmented villonodular synovitis
Giant cell tumour of the tendon sheath
Giant cell tumour of the bone
Describe pigmented villonodular synovitis
Occurs in the synovium of large joints
Can spread out with the joint
Most destructive and diffuse GST
Difficult to excise and will often recur
Describe giant cell tumours of the tendon sheaths
Small nodules
Occur in the digits
common and benign
Easily excised
Name the different types of lipoma
Fibrolipoma- contain lots of fibrous tissue
Angiolipoma – contain blood vessels
Spindle cell lipoma - contain spindle cell
Pleomorphic – cells look odd
Atypical lipoma
What is a lipoma
A fat tumour
What are the most common MSK causes of painful lumps in the superficial tissue
Angiolipoma Neuroma (traumatic) Glomus tumour (nail beds etc.) Eccrine spiradenoma (skin adnexal tumour) Cutaneous leiomyoma
What tumours can occur in the smooth muscle
Leiomyomas - common and benign
Leiomyosarcoma - malignant version, uncommon
Can occur anywhere in the body
What are tumours of skeletal muscle called
Rhabdomyomas
Benign lesions
Very rare
What are rhabdomyosarcomas
Malignant tumours of skeletal muscle
Can occur in GU tract or bile duct in childhood
Hard to diagnose
What are enchondroma
Benign cartilage tumours
Common in the digits
What are chondrosarcoma
Tend to affect older population - 40-50s
Common in the axial skeleton
What are common benign tumours of the bone
Osteoma - common in cranial bones
Multiple tumours can occur in Gardner’s syndrome
Describe malignant tumours of the bone
osteosarcoma
Usually in paediatrics
Affects the long bones
What is Ewing’s sarcoma
Malignant cells that can appear in any soft tissue or bone Small round blue cell tumours Most common in children and adolescents Destructive and highly malignant Unknown origin
What is nodular fasciitis
Rapid growth that can effect any age
Sometimes occurs after trauma
Chaotic appearance with large atypical cells
Haemorrhage is common
What is myositis ossificans
Lesion that occurs after preceding trauma
Affects the big muscles
Which joints does gout most often occur in
Peripheral joints
Thought to be due to lower temperatures allowing crystals to precipitate
Big toe is the commonest site
How common is gout in the UK
Prevalence of 1.4%
increasing due to obesity
More common in women
Rare before menopause
Why is gout uncommon before menopause
Oestrogen has a protective effect as it promoted uric acid excretion
How does acute gout present
Monoarthropathy - pain and inflammation
Swollen, red joint
Abrupt onset
Will settle in 10 days without treatment or 3 with
How do you treat acute gout
NSAIDs - diclofenac, naproxen
Use for symptom control until it self-resolves
Colchicine - used if they cannot take NSAIDs
Steroids - oral or injected into joint (very effective)
Stop diuretics as can precipitate and switch to a new drug
What can be used for prophylactic treatment of gout
Allopurinol
Febuxostat
Cover with NSAID for symptom control - stop after 6 weeks
Stop diuretics if possible
Lifestyle changes - lose weight, less alcohol and red meat
When do you use prophylactic treatment for gout
If the patient has 2 or more acute attacks in a year
Start 2-4 weeks after attack
If they have tophi
If they have renal impairment or history of renal calculi
Those with HF on diuretics who keep getting gout
How do you treat pseudogout
NSAIDS
Colchicine
Steroids
Rehydration
What causes Milwaukee shoulder and what are its effects
Deposition of hydroxyapatite crystals in or around joint
More common in women
Get an acute and fast deterioration of joint
How do you treat Milwaukee shoulder
NSAIDs
Intra-articular steroid injection
Physiotherapy
Partial or total arthroplasty
What is soft tissue rheumatism
Term used to describe pain caused by inflammation/damage to ligaments/tendons/muscles/nerves near a joint
Pain is confined to specific site
what are some common causes of soft tissue rheumatism in the shoulder
Adhesive Capsulitis Rotator cuff tendinosis Calcific tendonitis Impingement Partial rotator cuff tears Full rotator cuff tears
How do you investigate soft tissue pain
Usually tests are not necessary
X-ray if suspect calcific tendonitis
MRI if it doesn’t settle
How do you treat soft tissue pain
Pain control Rest and Ice compressions Physio Steroid injections Surgery
Who commonly has joint hypermobility syndrome
More common in women
Usually presents in childhood or 3rd decade
Associated with some rare genetic conditions -e.g. Marfan’s
How does joint hypermobility syndrome present
Arthralgia - pain
Premature osteoarthritis
Can be generalised or localised
Investigations will be normal
How do you treat joint hypermobility syndrome
Physio
Patient education
What abnormalities can cause intoeing
Femoral neck anteversion
Internal Tibial Torsion
Metatarsus adductus
Can be a combination
What is femoral neck anteversion
When the femur is orientated more anteriorly than normal
Usually doesn’t cause major issues, just slight knee problems or intoeing
What is internal tibial torsion
inward twisting of the tibia
Seen in 1-3 y/o and usually resolves by age 6
What metatarsus adductus
Common and benign deformity
Usually resolves but may need casting
Front of foot curves inwards
What is meant by flat feet
No defined arch in foot - should have developed in childhood
Usually asymptomatic
Can be flexible or fixed
Osteopenia is defined as a T-score of what?
Between −1 and −2.5 SD
The T-score is the number of SD (standard deviations) below the mean BMD of young adults at their peak bone mass
What is the SINGLE MOST appropriate initial treatment in general practice for giant cell arteritis in a patient presenting with visual manifestations
Prednisolone 60 mg daily
Why might a serum urate level be normal in acute gout
During an acute attack most of the uric acid is deposited in the joints and therefore serum levels can be completely normal or even low
Should repeat test a week after the episode has settled
Why shouldn’t you start allopurinol or other urate lowering drugs during acute gout
Any sudden changes in uric acid levels can
precipitate further attacks of gout or prevent the acute episode from
settling down
What other diagnosis must be ruled out if you suspect gout
Septic arthritis
Presents similarly
If really unsure treat as sepsis until proven otherwise
An acute presentation is suggestive of which rheum diseases
Acute = less than 6 weeks
Gout, septic arthritis etc.
A chronic presentation is suggestive of which rheum diseases
Chronic = over 6 weeks
RA, psoriatic arthritis etc
How does a rheum issue within the joints present
Pain, swelling, stiffness and limitation of movement
How does a rheum issue within the muscle present
myositis or myopathy
Pain in affected muscle, weakness, wasting if prolonged, no stiffness
How does a rheum issue within the soft tissue present
Localised pain, joint will function normally, only some movement affected.
Includes rotator cuff issues, trochanteric bursitis, epicondylitis.
Which rheum diseases are more likely to complain pf widespread pain rather than localised
Autoimmune issues or fibromyalgia
Which MSK conditions typically involve the spine
OA, spondyloarthropathies
Pain in RA is always constant - true or false
False
Whilst this is the most common presentation you can get palindromic RA which presents with intermittent pain
What is a monoarthropathy and give examples
Disease affecting one joint
Gout, reactive arthritis, septic etc
What is a oligoarthropathy and give examples
Disease affecting between 1-4 joints
Reactive arthritis, ankylosing spondylitis, psoriatic (seronegative spondylarthropathy)
What is a monoarthropathy and give examples
Disease affecting more than 4 joints
OA or RA
RA is typically symmetrical - true or false
True
List common symptoms of chronic pain syndromes
Poor sleep pattern, headaches, low mood or anxiety, IBS, irritable bladder, muscle spasms, brain fog
Which type of pain is worse at rest
Inflammatory pain
Which type of pain is worse on movement
Mechanical
Prolonged early morning stiffness (>1 hour) is suggestive of what
Inflammatory process
Alcohol use is associated with which joint issue
Associated with gout
Which MSK symptoms can be caused by statins
Muscle pain
tendon tears and tenosynovitis
Which MSK symptoms can be caused by gliptins and tamoxifen
Arthralgia
Which MSK symptoms can be caused by checkpoint immunotherapy (e.g. in cancer)
Arthritis
Which MSK symptoms can be caused by quinolones
tendon tears and tenosynovitis
Which MSK symptoms can be caused by diuretics
Gout - they reduce urate excretion
Which MSK symptoms can be caused by beta-blockers
Raynaud’s
HLA diseases can run in families - true or false
True
Things like RA etc
Methotrexate is hepatotoxic - true or false
True
Be careful in alcoholics
Ankylosing spondylitis progresses slower in smokers - true or false
False
Progresses more rapidly
Why is menstrual history relevant in MSK/rheum histories
Gout is rare pre-menopause
OA can be worse during or after menopause
Early menopause increases risk of osteoporosis
