RHEUMA Flashcards
Polarized light microscopy can identify most typical crystals except for
Apatite
Gpout is caused by deposition of what crystals
MSU crystals
The most common early clinical manifestation of gout
Acute arthritis
Only one joint is affected initially
Inflamed nodes which may be a first manifestation of gouty arthritis (2)
Heberden’s or Bouchard’s nodes
Women represent only ____ of all patients with gout
5–20%
Mostly postmenopausal and elderly
Often demonstrated in the first metatarsophalangeal joint and in knees not acutely involved with gout during acute gouty attacks
Needle-shaped MSU crystals
Thick pasty or chalky joint fluid in gout/tophi is due to
large number of crystals
In 24-h urine uric acid, this value of of uric acid per 24 h on a regular diet suggests that causes of overproduction of purine should be considered
> 800 mg
Ultrasound of gout show what sign?
double contour sign overlying the articular cartilage
2 regimens of colchine in gout
- One 0.6-mg tablet given every 8 h with subsequent tapering
* 1.2 mg followed by 0.6 mg in 1 h with subsequent day dosing depending on response
Mainstays of treatment of acute gout (3)
- NSAIDs
- Colchicine
- Glucocorticoids
Intraarticular glucocorticosteroids used in acute gout (2)
- Triamcinolone acetonide (20–40 mg)
* Methylprednisolone (25–50 mg)
To prevent recurrent gouty attacks and eliminate tophaceous deposits, we should normalized SUA to
<300–360 μmol/L (5.0–6.0 mg/dL)
Factors affecting decision to initiate hypouricemic therapy in gout (4)
- Number of acute attacks (urate lowering may be cost-effective after two attacks)
- Serum uric acid levels (progression is more rapid in patients with serum uric acid >535 μmol/L [>9.0 mg/dL])
- Patient’s willingness to commit to lifelong therapy
- Presence of uric acid stones
Uricosuric agents for patients with good renal function who underexcrete uric acid (<600 mg in a 24-h urine sample)
Probenecid
Dose: 250 mg twice daily and increased gradually as needed up to 3 g per day to achieve and maintain a serum uric acid level of <6 mg/dL
In patiets taking probenecid, urine volume should be maintained by ingestion of _____ of water every day
1500 mL
Nonspecific xanthine oxidase inhibitor used in gout
Allopurinol
Specific xanthine oxidase inhibitor used in gout
Febuxostat
Most commonly used hypouricemic agent
Allopurinol
Best drug to lower serum urate in overproducers, urate stone formers, and patients with renal disease
Allopurinol
Dose of allopurinol in gout
100 mg initially and increasing up to 800 mg if needed
Allopurinol toxicity is increased in patients with (2)
- Intake of thiazide
2. Allergy to penicillin and ampicillin
A pegylated uricase for gout patients who do not tolerate or fail full doses of other treatments
Pegloticase
Colchicine anti-inflammatory prophylaxis in doses of 0.6 mg one to two
times daily should be given along with the hypouricemic therapy until (3):
- Patient is normouricemic
- Without gouty attacks for 6 months
- As long as tophi are present
Colchicine should NOT be used in dialysis patients
Calcium pyrophosphate deposition disease is most common in what group of patients
Elderly
Mutations in the ANKH gene will cause
Calcium pyrophosphate deposition disease
A minority of patients with CPPD arthropathy have hereditary CPP disease or these metabolic abnormalities (4)
- Hyperparathyroidism
- Hemochromatosis
- Hypophosphatasia
- Hypomagnesemia
Originally was termed pseudogout
Acute calcium pyrophosphate deposition disease arthritis
The joint most frequently affected in CPPD arthropathy
Knee
Other sites: • Wrist • Shoulder • Ankle • Elbow • Hands • Temporomandibular joint
Punctate and/or linear radiodense deposits within fibrocartilaginous joint menisci or articular hyaline cartilage seen in radiograph or ultrasound.
Chondrocalcinosis
Chondrocalcinosis is presumptive of
CPPD
DDx: CaOx in some patients with chronic renal failure
Demonstration of typical rhomboid or rodlike crystals (generally weakly positively birefringent or nonbirefringent with polarized light) in synovial fluid or articular tissue is diagnostic of
CPPD
Acute attacks of CPPD arthritis may be precipitated by (3)
- Trauma
- Severe medical illness
- Surgery
Acute attacks of CPPD arthritis may be precipitated by surgery most especially,
Parathyroidectomy
causes rapid diminution of serum calcium concentration
Aka basic calcium phosphate disease
Calcium apatite deposition disease
Aka apatite arthropathy
the primary mineral of normal bone and teeth
Apatite
In CKD, this contribute to extensive apatite deposition both in and around joints
Hyperphosphatemia
Apatite aggregates are commonly present in synovial fluid in an extremely destructive chronic arthropathy of the elderly that occurs most often in the
shoulders (Milwaukee shoulder)
may also occur in hips, knees, and erosive osteoarthritis of fingers
30–50% of patients with ________ have apatite microcrystals in their synovial fluid
Osteoarthritis
Acute attacks of bursitis, tendinitis or synovitis is seen in what joint disease
Calcium apatite deposition disease
A rare hereditary metabolic disorder that may lead to nephrocalcinosis and renal failure
Primary oxalosis
Common cause of secondary oxalosis
Ascorbic acid supplements
Bipyramidal crystals with strong birefringence and may stain with alizarin red S
CaOx crystals
____ of SLE cases occur in women of child-bearing age
90%
Genetic “signature” in peripheral blood cells of 50-80% of SLE patients
Upregulation of genes induced by IFNs
The most characteristic gene expression pattern of SLE patients
Influence the IFN production
Female sex is permissive for SLE because of (3)
- Hormone effects
- Genes on the X chromosomes
- Epigenetic differences between genders
SLE is associated with prolonged occupational exposure to
crystalline silica
Social behavior or lifestyle that reduces risk of SLE
Alcohol (2 glasses of wine a week or ½ of an alcoholic drink daily)
Biopsy of SLE shows (3)
- Deposition of Ig at the dermal-epidermal junction (DEJ)
- Injury to basal keratinocytes
- Inflammation dominated by T lymphocytes in the DEJ and around the blood vessels and dermal appendages
The abovementioned patterns are NOT specific for dermatologic SLE, but they are highly suggestive
Class of lupus nephritis that requires aggressive immunosuppression (3)
- Class III
- Class IV
- Class V, accompanied by III and IV
Class of lupus nephritis that does not require aggressive immunosuppression (3)
- Class I
- Class II
- With extensive irreversible changes