· systemic connective tissue disease
· chronic inflammatory disease resulting from abnormal immunoregulation
· unknown
· thought similar to RA
· genetic factors
· environmental factors
· young females
· F:M 9:1
· peak age 35
· geographic variations
· more common in Africans and Asiana
· affecs many organ systems
· bones
· joints
· tendons
· skin
· heart
· kidney
· CNS
· most common features are
· systemic (malaise, fever, anorexia, weight loss)
· skin rashes (esp. photosensitive butterfly rash of face)
· Reynaud’s phenomenon
· peripheral vasculitis
· splenomegaly
Joint involvement
· arthritis or arthralgia is presenting feature in >90%
· usually involves small joints
· morning stiffness in 50%
· symmetrical involvement
· long-standing disease may produce RA-like deformity
· different to RA in that
· no ankylosis or contractures
· deformity due to subluxation from capsular laxity and tendon involvement
· no erosive change on x-ray
Avascular necrosis
· increased incidence of AVN
· disease predisposes to bone ischaemia
· aggravated by corticosteroids
· most positive for antinuclear antibodies (ANA)
· anti-DNA antibody test most specific
· usually
· elevated ESR
· anaemia, leucopaenia, thrombocytopaenia
· elevated acute phase proteins
· related to disease activity and target organ
· may use
· NSAIDs
· corticosteroids
· antimalarials
· immunosuppressives
· revolves around
· joint involvement
· AVN
· arthoplasty patients have increased risks
· infection
· ligamentous imbalance
· loosening from osteopaenia
· fracture from osteopaenia