Rheumatoid Arthritis Flashcards
what is RA?
an autoimmune symmetrical inflammatory arthritis
what gene mediates RA
HLA DR4
pathophysiology of RA development
IgG forms against cartilage – rheumatoid factor (IgM antibody) forms in response to IgG – synovitis – pannus + joint destruction
what is pannus
deposits in the synovial membrane - inflamed, spongy synovium
what gender is RA more common in
3x more common in females
most specific antibodies in RA
anti-CCP - worse prognosis if present
what joints are most commonly affected by RA
small joints of hands + feet - MCP - PIP - MTP
what joints of hands + feet does RA typically spare
thumb + 1st MTP
what is tenosynovitis?
inflammation of synovium that surrounds a tendon - affects flexors in RA
what deformities may be seen in longstanding disease
ulnar deviation dorsal wrist subluxation boutonniere + swan neck deformities
difference between boutonniere and swan neck deformities
boutonniere causes flexion at PIP
swan neck causes flexion DIP
when are symptoms of RA worse
worse in the morning with >30 mins stiffness
- improves as day goes on
systemic symptoms of RA
fatigue
fever
weight loss
skin manifestations of RA
Rheumatoid nodules
Pyoderma gangrenosum
Erythema nodosum
what nerve entrapment is common in RA
Carpal tunnel syndrome
- compression of median nerve
- pain/numbness in thumb, index + middle finger
what eye conditions are associated with RA
Keratoconjunctivitis Sicca - dryness of conjunctiva
Scleritis - painful red eye + gradual vision decrease
Episcleritis - non-painful red eye
what cardiac valve disease is associated with RA
mitral regurgitation
- pansystolic blowing murmur
- best heard at apex
- radiates to axilla
features of rheumatoid lung disease
Pulmonary fibrosis
Pleural effusion
methotrexate pneumonitis
RA, RF +ve, splenomegaly and neutropenia
classical of what syndrome?
Felty’s syndrome
XRAY findings in RA
Juxta-articular osteoporosis
Periarticular erosions
Subluxation
Loss of joint space
what scoring system is used for RA
DAS 28
- disease activity score that assesses 28 joints
What DAS score indicates severe active disease
>5.1
What DAS score indicates remission
<2.6
what inflammatory markers may be raised in RA
ESR
CRP
1st line treatment for RA
Methotrexate (DMARD) + short course prednisolone as bridging therapy
how is methotrexate taken
oral, once a week
what is given along side methotrexate in RA
Folic acid
is methotrexate safe in pregnancy
NO
- stop 3 months before trying to conceive
what must be monitored on methotrexate + why
LFTS - risk of liver cirrhosis
FBC - risk of myelosuppresion
resp side effect of methotrexate
pneumonitis
2nd line DMARD
Sulfasalazine (aminosalicylate)
when would use of TNF-inhibitors be considered
inadequate response to 2 DMARDS, including methotrexate
examples of TNF inhibitors
what condition do they increase risk of reactivating?
etanercept
infliximab
- reactivation of TB
How are flares of RA managed
oral or IM steroids
what drug must you be cautious in prescribing in patient with an aspirin allergy
sulfasalazine
