Rheumatology Flashcards
What is the most commonly affected joint in pseudogout?
Knee
What are the common clinical signs of an inflammatory arthritis
Hot, swollen, tender joints with reduced ROM and loss of function
What antibodies are present in Sjogrens syndrome that are specific for the disease
Anti- Ro (anti SSA) and Anti-La (anti SSB)
What is the typical presentation that would warrant further investigation for Sjogren syndrome
Xerostomia (dry mouth) and Xeropthalmia (dry eyes) - combination is known as sicca. Patients often complain of having gritty eyes and difficulty swallowing from reduced saliva
What disease state are people with Sjogrens syndrome at higher rates of developing
Non-Hodgkins Lymphoma (MALT)
What antibody has high specificity for RA
Anti CCP
Variations in which gene are strongly associated with RA
HLA-DRB1 (has alleles that display the ‘shared epitope’)
What environmental triggers are strongly assosciated with RA
Lung - smoking/silica exposure; Mouth - P gingivalis bacterial disease; Gut - factors that alter the microbiome including sugary drinks and repeated exposure to ABx
What is the first line DMARD that should be used for RA
Methotrexate
In a gout flare, should you increase the dose of allopurinol
No - continue allopurinol at the current dose and introduce a short term anti-inflammatory drug (NSAID, colchicine, IL1 antagonist). Altering the dose of allopurinol has the risk of sudden changes in serum urate levels which can trigger/propagate gout flares
What is the most common site of venous and arterial thrombosis in antiphospholipid syndrome?
Venous - Deep veins of lower extremities
Arterial - Cerebral circulation
What are the obstetric complications of antiphospholipid syndrome?
- Recurrent early (<10 weeks) miscarriages
- Foetal demise beyond 10 weeks
- Premature births ( <34 weeks) associated with eclampsia/preeclampsia or placental insufficiency
Which rheumatological disorder is most commonly associated with antiphohpholipid syndrome?
SLE
What is catastrophic APS (CAPS)?
Catastrophic APS is a life-threatening progressive macro and microvascular thromboembolic disease involving 3 or more organs simultaneously or over a short time course (occurs in 1% of people with APS)
What are the risk factors for catastrophic APS?
Risk factor for CAPS: Infection, surgery, cancer, estrogen use, pregnancy/postpartum, active SLE
What are the diagnostic criteria for antiphospholipid syndrome?
Diagnosis of APS requires presence of at least one clinical and one lab criteria.
Clinical criteria
- Unprovoked venous, arterial or small vessel thrombotic events
- Obstetric complications - early miscarriage (<10 weeks), foetal loss after 10 weeks gestation, premature birth (< 34 weeks) from pre-eclampsia or placental insufficiency
Lab criteria: Positive aPL abs on 2 separate occasions a least 12 weeks apart
- Lupus anticoagulant
- Anticardiolipin abs (IgG and M)
- Beta2glycoprotein I abs (IgG and M)
What are the diagnostic criteria for catastrophic APS?
Diagnosis of CAPS
- Involvement of ≥3 organs, systems, or tissues
- Manifestations develop simultaneously or over <1 week
- Small vessel occlusion is confirmed histologically in at least one organ or tissue
- Presence of aPL (anticardiolipin antibodies, anti-beta2-glycoprotein I antibodies, and/or lupus anticoagulant) is documented twice, at least 12 weeks apart
What are the thrombotic manifestations of antiphospholipid syndrome?
Venous thrombosis:
- DVT (most common 39%)
- PE
- Livedo reticularis - Blood clots in capillaries lead to swelling of venules, resulting in a purplish, net-like discoloration of the skin.
Arterial thrombosis:
- Stroke and TIA (most common 20%)
- Occlusion of organ arteries (e.g. MI, retina, renal)
- Occlusion of arteries supplying extremities (ischemia and gangrene)
Capillary thrombosis:
- Splinter haemorrhages
What are the non thrombotic manifestations of antiphospholipid syndrome?
Valvular heart disease and cognitive decline
What are the three antibodies that are included in the diagnostic criteria for APS? What do FBC and coagulation profile show in APS?
Lupus anticoagulant
Anticardiolipin Ab (IgG or M)
Beta2glycoprotein1 Ab (IgG or M)
FBC: thrombocytopenia, haemolytic anaemia (autoimmune or microangiopathic)
Coagulation: prolonged aPTT
Which infectious disease do patients with APS often test falsely positive for?
Syphilis (the test to detect it uses cardiolipin antigen)
What is the treatment of antiphospholipid syndrome?
Primary prevention: for patients with aPL abs but no thrombotic event or obstetric complication - low dose aspirin
Secondary prevention: lifelong anticoagulation with warfarin. For venous thrombosis, warfarin (INR target 2-3), for arterial warfarin (INR 2-3) and low dose aspirin (75-100 mg). Recurrent thrombosis despite adequate INR – switch to LMWH, change INR target to higher, add aspirin or hydroxycholorquine
- Obstetric APS – previous history APS obstetric complication – prophylactic dose LMWH and low dose aspirin recommended; thrombotic APS – therapeutic LMWH + low dose aspirin should be administered. For recurrent obstetric complications despite above treatment consider IVIG and hydroxychloroquine. Warfarin is teratogenic and contraindicated in pregnancy. Warfarin therapy recommended post partum in patients with risk of recurrent thrombosis.
What is the treatment for catastrophic APS?
Combination therapy with glucocorticoids, heparin, and plasma exchange or IVIG together with appropriate management of triggering events such as infections. For refractory CAPS, B-cell depletion (e.g., with rituximab) or complement inhibition (e.g., with eculizumab) therapies are alternative options.
What are the characteristic histopathological features of IgG4 disease?
- Lymphoplasmacytic tissue infiltration of mainly IgG4-positive plasma cells and lymphocytes
- Storiform fibrosis
- Obliterative phlebitis
- Modest tissue eosinophilia
