L07: Cystalline Disease Flashcards
What is gout
An inflammatory disease caused by the deposition of monosodium urate (MSU) crystals in the joint and other tissue
What are formation of crystals a consequence of in gout
Hyperuricaemia: serum uric acid more than 6mg/dl
Deposits of MSU crystals known as to phi may form in and around joints but also elsewhere
What are the causes of Hyperuricaemia
Decreased fractional excretion via kidneys
Increased ingestion: beer, fructose rich beverage
Increased degradation: high cell turn over in psoriasis, haemotological malignancy
Advancing age
Genetic mutations
What are the local factors for MSU crystal deposition
Formation of uric acid crystals will depen on:
Concentration of urate
Articular hydration state
Temperature
Ph
Presence of extracellular matrix proteins
What is the association between gout and osteoarthritis
The cartilage damage in osteoarthritis can exposure collagen fibres that can act as template to promote MSU crystal nucleation
What are the clinical features of gout
There are 3 periods to gout:
Asymptomatic hyperurasemia
Acute attack of asymptomatic intervals
Chronic gout
What is acute gout characterised by
Rapid onset of symptoms Pain Swelling Unable to bear bed clothes Can affect one single joint in the lower limb e.g 1st metatarsal pharyngeal joint Fever
What are the differential diagnosis for gout
Reactive arthritis
Mono articular presentation of rheumatoid arthritis
Septic arthritis
What are the investigations for gout
Blood: FBC, raised ESR/CRP
Renal function and urate
Blood culture: infection
Synovial fluid: polarised light microscopy for crystals
What is the management of gout if acute
NSAIDs or Colchicine (first line)
Corticosteroids
Ice
What is the chronic treatment for gout
Lifestyle advice: reduce alcohol intake
Colchine or NSAID if not tolerated
Allopurinol
What is pseudogout
Microcrystalline synovitis caused by the deposition of calcium pyrophosphate (CPP) dihydrate crystals in the synovium
What are the risk factors for pseudogout
Hyperparathyrodisim- hypercalcium
Low magnesium
Low phosphate
What is the diagnosis of pseudogout by
Identification of CPP crystals in the synovial fluid joint aspiration
X-ray: chondracalcinosis
What is the management of pseudogout
NSAIDs
Colchicine
Steroid
What is Spondylarthropathy
A term given to related inflammatory arthropathies that have common features of:
Inflammation of the spine
Sacro iliac involvement
Enthesis (point of attachment of a ligament or tendon to a bone that is inflammed)
What conditions are Spondylarthropathy
Ankylosing spondylitis Reactive arthritis Psoriatic arthritis Enteropathic spongylathropathy Undifferentiated Spondylarthropathy
What are the causes of Spondylarthropathy
Genetic factors: HLAB27
Environmental factors
Infective triggers
What are the common features of Spondylarthropathy
Sacroiliac and Spinal involvement: chronic pain, back pain, buttock pain
Enthesitis
Peripheral asymmetric arthritis
Dactylitis: this is painful swelling of whole digit
Ocular inflammation: painful, red eye
Skin lesions
What does ankylosing spondylitis present as
In young adults
Inflammatory back pain and stiffness
What are the features of ankylosing spondylitis
Chronic lower back pain
Pain worse in the morning and wakes someone up
Peripheral synovitis at hips and shoulders
Chest wall pain
Extra articular manifestations; peripheral arthritis, iritis, colitis, pulmonary fibrosis
What is the criteria to diagnose ankylosing spondylitis
Inflammatory back pain for more than 3 months with 1 or more of: Alternate buttock pain Sacroilitis on x-ray Positive family history IBD Psoriasis Enthesopathy
What are the investigations for ankylosing spondylitis
Bloods: ESR, CRP, usually raised
X-ray: sacroiliac joints
Ultrasound Doppler for enthesitis
What is the pharmacological management of as
NSAID
DMARD (methotrexate, anti tnf, corticosteroids, suphasalazine)
