Rheumatology : Key Conditions Flashcards
Reactive Arthritis
- Presentation
Triad of arthritis, urethritis and conjunctivitis.
- peripheral arthritis 1-4 weeks after infection, commonly an asymmetrical oligoarthritis but may be polyarticular/ monoarticular, usually affecting larger joints in lower limb
- Axial arthritis
- recently had a viral or bacterial infection (STI common)
- no direct infection in the joint, but it can cause symmetric hand and feet arthritis.
Extra-articular features of Reactive Arthritis (3)
Constitutional symptoms
Enthesitis:Achilles tendonitis or plantar fasciitis
Painless mucosal ulcers
Dark maculopapular rash on palms and soles called keratoderma blenorrhagica
Ocular inflammation: conjunctivitis and anterior uveitis
Urethritis and sterile dysuria, inflammation of bladder and prostate may cause cystitis and prostatitis
Circinate balanitis (painless ulceration of glans)
Aphthous ulcers in the mouth
Anterior uveitis
Erythema nodosum
Reactive Arthritis
- Investigations and Mx
Bedside
- stool MC&S and urethral / cervical swabs for chlamydia.
Blood tests
CRP , ESR
Seronegative
HLA-B27- supportive only
Imaging
Joint X-rays usually appear normal and changes are only seen in severe, chronic disease.
Pelvic X-rays may show sacroiliitis, and spinal X-rays may show squaring of vertebrae and syndesmophytes creating a “bamboo spine”, as in ankylosing spondylitis.
Treatment
- NSAIDs
- possibly corticosteroid injections.
- severe subset may require DMARDs to prevent joint damage.
How is a diagnosis of limited cutaneous systemic sclerosis made?
Anti-centromere antibodies (90%)
- specific to limited cutaneous SSc.
- Note: Most patients are ANA positive
How is a diagnosis of diffuse systemic sclerosis made?
Anti-Scl-70 antibodies
- specific to diffuse cutaneous SSc.
- Note: Most patients are ANA positive
Diffuse systemic sclerosis
- Multi-system autoimmune disease
- Skin involvement is over widespread areas at onset and is characterised by early visceral involvement.
Limited (cutaneous) systemic sclerosis
- Features
Skin fibrosis is limited to the hands and forearms, feet and legs, and the head and neck.
CREST Calcinosis Raynaud's oEsophageal dysmotility Sclerodactyly Telangiectasia.
Rare complication of systemic sclerosis
Scleroderma renal crisis
Initial Mx- Captopril
- worsening kidney failure and high BP
- ACEi to reduce BP
Risk factors for pseudogout
Advanced age
Injury or previous joint surgery
Hyperparathyroidism
Haemochromatosis
Hypomagnesaemia
Hypophosphataemia
Microscopy findings in Pseudogout
Positively berefringent romboid shaped crystals made of calcium pyrophosphate
Treatment for acute episodes of pseudogout
(1) Treatment is usually with a course of NSAIDs.
(2) If NSAIDs are contraindicated, a course of colchicine may be used instead. Colchicine is problematic because it is very prone to causing significant GI disturbances, especially diarrhoea.
(3) If both NSAIDs and colchicine are contraindicated, a short course of oral steroids, or an intra-articular steroid injection may be used.
Specific antibodies for Sjogrens
Anti-Ro and Anti-La Autoantibodies are both specific for Sjogren’s syndrome.
What test can aid in the diagnosis of Sjogrens?
Schirmer’s test - this demonstrates reduced tear production using a strip of filter paper on the lower eyelid: wetting of <5mm is positive.
Acute management lupus nephritis
- High dose prednisolone
- Cyclophosphamide (fertility issues)
Common organisms in septic arthritis
The most common organism that causes septic arthritis is Staphylococcus Aureus.
Gonococcus: commonest in young sexually active individuals
Streptococcus
Gram negative bacilli