Crystal induced arthritis Flashcards
3 main types of crystal induced arthritis
- gout
- calcium pyrophosphate dihydrate deposition disease
- basic calcium phosphate deposition disease
Definition of gout
A form of arthritis caused by deposition of monosodium urate crystals within joints, associated with chronic hyperuricaemia
At what concentration of urate is there risk of MSU crystal formation?
0.38 mmol/L
Pro-inflammatory mediators that cause problems in gout
- IL- 1B
- TNF a
- IL-8
Factors that influence uric acid production
- purine ingestion
- de-novo synthesis of purine in cells
- recycling
- degradation function of xanthine oxidase
Which transporter is responsible for reabsorption of urate by kidneys?
URAT1
Name for gout in big toe
Podagra
Factors that might trigger acute gouty attacks
- alcohol
- meat and seafood
- fasting
- trauma
- surgery
- drugs
What characterises chronic gout?
- destructive polyarticular involvement
- low-grade joint involvement
- joint deformity
- tophi
Characteristics of gout under polraised microscopy
- strongly bifringent
- appear very bright
Most common type of gout-related nephropathy
Kidney stones
Treatment of acute gout attackes
- high dose NSAIDs
- colchicine (0.5mg 2-4 times a day)
- corticosteroids
Treatment of hyperuricaemia
Uricostatic drugs (XO inhibitors - allopurinol) Uricosuric drugs (URAT1 inhibitors - losartan, probenecid) Uricolytic drugs (recombinant uricase - pegloticase)
Prophylaxis for gout
- colchicine 0.5mg 2 times a day for 3-6 months
- low dose NSAIDs for 6-12 weeks
Possible presentations of CPPD
- acute inflammatory arthritis (psuedogout)
- pseudo-OA
- OA-like presentation with discrete acute attacks
- pseudo-RA
- Psuedo-Charcot
- asymptomatic chondrocalcinosis on X-rays
Where is chondrocalcinosis often found?
- knee
- wrist
- symphysis pubis
Conditions associated with chondrocalcinosis
- hyperparathyroidism
- haemochromatosis
- hypophosphatasia
- hypomagnesemia
- gout, Wilson’s disease
Diagnostic tests for CPPD
- CPPD crystals in synovial fliud
- plain radiograph
- U/S
- CT scan
- new MRI modalitis
- EM and X-ray diffraction
What do CPPD crystals look like
positively bifringent rhomboid-shaped crystals
Treatment of CPPD
- resting the joint
- NSAIDS
- intra-articular steroid injections
- colchicine (psuedogout)
- systemic corticosteroids
- hydroxychloroquine (chronic arthritis)
Types of basic calcium phosphate crystals
- carbonate-substituted hydroxyapatite
- tricalcium phosphate
- otacalcium phosphate
What is BCP deposition disease associated with?
- Milwaukee Shoulder syndrome
- OA
- calcific periarthritis, bursitis and tendinitis
- limited systemic sclerosis
- dermatomyositis
- mixed crystal deposition disease
- chronic renal failure
- hypercalcaemia
Treatment of BCP arthropathy
- NSAIDs
- intra-articular steroid injection
- physiotherapy
