1. Metabolic conditions and the musculoskeletal system
Johan van Rensburg

2. CRYSTAL-INDUCED ARTHRITIS

3. TYPES Monosodium urate monohydrate Calcium pyrophosphate
Calcium hydroxyapatite
Cholesterol

4. URIC ACID POOL Endogenous Exogenous Excretion Kidneys (2/3)
Intestines (1/3)
Serum urate: 0, ,55mmol/l
Urine urate excretion: 1, ,4mmol/24 hours

5. MECHANISM OF HYPERURICAEMIA
Overproduction
Underexcretion

6. HYPERURICAEMIA AND GOUT
(MONOSODIUM URATE)
disorder of purine metabolism
characterised
hyperuricaemia
deposition of uric acid or urate crystals in the tissues
manifests as
acute attacks of gouty arthritis
tophi
kidney stones
urate-nephropathy

7. PATHOGENESIS
Hyperuricaemia causes gout, but is not synonomous with gout
Factors promoting crystallisation (0.55mmol/l)
the level of saturation
solubility
pH and temperature of the limb

8. PATHOGENESIS Crystallisation in joint Crystal absorbed by PMN
Secretion lysozyme enzymes
Severe synovitis

10. ACUTE GOUTY ARTHRITIS INCIDENCE Mostly men > 40yrs
Sometimes postmenopausal women
(Often on Diuretics)

11. CLINIAL PICTURE ACUTE GOUTY ARTHRITIS
Goes to bed healthy
Wakes up sudden monoarthritis ( 85% Podagra)
(heel, instep, knee, wrist and hands and elbow -olecranon bursitis)
Rigors with severe pain
Night spent in torture
Joint is red (“ripe tomato”),warm and very tender.
After attack skin around the joint often peels off
Acute attacks usually pass completely until the next attack
Uncontrolled hyperuricaemia may lead to polyarticular gout

12. ACUTE GOUTY ARTHRITIS

13. PERCIPITATING CAUSES ACUTE GOUTY ARTHRITIS
Trauma and surgery
Medication
Alcohol
Diet

14. ACUTE GOUTY ARTHRITIS

15. DIAGNOSIS OF GOUT
Family history, as well as a typical history of attacks
Typical clinical picture and tophi
Elevated serum urate - (may be normal during attacks)
Urate crystals in aspiration fluid (as well as tophi)
X rays: Punched-out erosions (Rat bitten)

17. TREATMENT Exclude precipitating causes
A low purine diet and avoidance of alcohol are recommended
Foods with a very high purine content: anchovy, sardines, liver and kidneys. Most meats, fish and chicken products also have a high purine content.
Treatment of acute attacks
Long-term preventive treatment
Treatment of associated conditions such as
obesity
hypertension
hyperlipaemia
kidney failure

18. RX ACUTE ATTACK Avoid initiation of prophylactics with an acute attack
Prophylactic therapy is not discontinued if a patient is already on therapy
NSAIDS ( not used in kidney failure)
Colchicine
Corticosteroids (in resistant cases)

19. Prevention ?

20. Progression in the disease
Asymptomatic hyperuricaemia
continues until possible first attack
Acute gouty arthritis
Interval hyperuricaemia
periods between attacks
Chronic tophaceous gout
Complications
kidney stones and nephropathy

21. CHRONIC TOPHACEOUS GOUT
Deposition of uric acid crystals in the tissues (tophi)
After repeated attacks after years
The tophi occur in
The auricles - helix
Tendons (hands, achilles tendon and feet)
Bursae - especially olecranon bursa
The tophi may ulcerate with secretion of pasty material

22. TOPHI

24. GOUTY TOPHUS

25. INDICATIONS FOR LONG-TERM PROPHYLACTIC THERAPY
If conservative measures do not have the desired effect and the levels still remain high (> mmol/l) with repeated attacks
(If less than 1 attack per year is experienced, treatment is not necessary)
Positive family history of gout and kidney stones with very high urate levels
Chronic tophaceous gout
Kidney stones or nephropathy

26. MEDICINES FOR LONG-TERM PROPHYLAXIS
Allopurinol 300mg/day
Uricosurics medicines
Probenecid 250mg bd
Must not be used if there is kidney failure or kidney stones
To avoid kidney stones a high fluid intake (2l/day) must be maintained and in addition the urine can be alkalised with something like “citrosoda”
Colchicine 0.5mg should be added once or twice daily for the first few months in order to prevent recurrent attacks

27. CPPD

28. DEFINITION
Arthropathy and other locomotor disease associated with CPPD crystal deposition
Sporadic, familial, and metabolic disease-associated forms recognized

29. CLINICAL FEATURES Predominantly a disease of the elderly
Acute self-limiting synovitis (‘pseudogout’)
Chronic arthropathy showing strong association/overlap with OA
Target joints – knees, wrists (shoulders, hips)

30. EPIDEMIOLOGY Female preponderance Rare under age 50,
10–15% in those aged 65–75
30–60% in those over 85 years
Framingham study
showed an overall prevalence rate of 8
27% in those >85 years

31. METABOLIC ASSOCIATIONS
Many reflect chance concurrence of common age-related conditions
Diabetes
Uremia
Paget’s disease
Hypothyroidism
Ochronosis
Gout

32. STRONGEST EVIDENCE Hyperparathyroidism Hemochromatosis
Hypophosphatasia
Hypomagnesemia
Wilson’s disease

33. COMMON PRESENTATIONS Acute synovitis Chronic arthritis
Incidental finding

34. DISTRIBUTION Any joint may be involved Knee commonest site Followed by
wrist
shoulder
ankle
elbow

36. INVESTIGATIONS Fluid and tissue analysis Plain radiographs
Other investigations may be undertaken to exclude alternative or coexisting arthropathy

37. CPPD Crystal Identification
Aspirated fluid turbid / blood-stained
Greatly elevated cell count (usually >90% neutrophils).
CPPD crystals poorly visualized LM
Polarized light microscopy
Morphology (usually rhomboids or rods)
Weak positive birefringence
May often be missed

40. RADIOGRAPHIC
Calcification
Structural changes

41. CALCIFICATION Fibrocartilage Also in hyaline cartilage
knee menisci
wrist triangular cartilage
symphysis pubis
Also in hyaline cartilage
Capsular and synovial calcification is less common
metacarpophalangeal joints and knee

44. ACHILLIS CALCIFICATION

45. PATELLOFEMORAL

47. Additional Investigations
Aspirated fluid
Gram stain and culture
Moderate acute phase response
Elevation
plasma viscosity
ESR
acute phase reactants (e.g. C reactive protein)
peripheral white cell count (neutrophils)

48. SCREENING Predisposing Metabolic Disease Unrewarding
Warranted in the following circumstances
early onset arthritis (<55 yrs)
florid polyarticular
recurrent acute attacks
additional clinical or radiographic clues

49. BLANKET SCREEN Serum calcium Alkaline phosphatase Magnesium Ferritin
Liver function

50. TREATMENT
Colchichine
IAI/draining
Saline levage
Ytrium
Surgery