Connective tissue diseases Flashcards
SLE Scleroderma Sjogren's syndrome Autoimmune myositis Giant cell arteritis
SLE definition (4)
a systemic autoimmune disorder
widespread deposition of immune complexes containing autoantigen and autoantibody
type III hypersensitivity
predilection for skin, joints, kidney
What autoantibody is present in >95% of SLE patients?
ANA is present in >95% of SLE patients
Explain the sensitivity and specificity of ANA for SLE
High sensitivity for SLE but low specificity for SLE
SLE: epidemiology
Gender distribution
Ethnicity
Onset
SLE epidemiology
F:M 9:1
Afro-Caribbeans > Asian > White
young - 15-50 yo
Classification criteria for SLE [11]
Malar rash Discoid rash Non-scarring alopecia Oral/nasal ulcers Synovitis Serositis - pleurisy or pericarditis Renal involvement Neurological Hematological Immunological Lab criteria
Name 2 renal features of SLE part of the classification criteria
Significant proteinuria
Cellular casts in urine
Name 3 hematological features of SLE
Low WCC
Low platelets
Hemolytic anemia
Scleroderma: epidemiology
F:M 3:1
Scleroderma: onset
30-50 yo
Scleroderma define
Chronic
Thickening and hardening of skin
Name 3 types of scleroderma
Scleroderma morphea/ localized scleroderma
Limited cutaneous scleroderma (subtype CREST)
Diffuse systemic scleroderma
Scleroderma morphea characteristics (3)
Prognosis and mortality
Localised patches of hardened skin - smooth and shiny
On trunk
No internal organ involvement
Good prognosis, low mortality
CREST syndrome - affected areas (2)
What antibodies to test for [2]
Face, distal limbs
No trunk involvement or proximal limbs
Mild pulmonary HTN
ANA, Anti-Centromere antibody
What is sclerodactyly [3]
localized thickening and tightness of skin of fingers/toes [1]
often leads to skin ulceration of distal digits, [1] commonly accompanied by atrophy of underlying soft tissues [1]
Complications of
CREST syndrome [1]
Diffuse systemic [3]
Pulmonary hypertension
Diffuse systemic
- Pulmonary hypertension and fibrosis
- Small bowel bacterial overgrowth
- Renal crisis
Diffuse systemic scleroderma
Affected areas
Progression
Autoabs to test for [2]
Affected areas: trunk and proximal limbs
Rapidly progressive
Progressing to organs e.g. kidney, heart, lungs, GIT
ANA, Anti-SCL70
Treatment of scleroderma
Symptomatic [4]
Diffuse [1]
Symptomatic:
- Raynaud’s: CCB, sildenafil
- Myositis: CCS
- Renal crisis: ACEI
- Cardiac: anti-arrhythmic
Diffuse:
- late stage pencillamine
Sjogren’s syndrome
Epidemiology - gender
Onset
F:M 9:1
Onset - 40-50 yo
Clinical features of Sjogren’s syndrome
Dry eyes, mouth
Parotid gland enlargement
Systemic symptoms: fatigue, fever, myalgia, arthralgia
Ix Sjogren’s [2]
Lab diagnostic tests [2]
Schirmer's test - to measure tear production Minor salivary gland biopsy Lab: ANA, Anti-Ro, Anti-La RF positive
Autoimmune myositis
Prevalence
2 types
Rare as it is 6 per million incidence
Polymyositis
Dermatomyositis
Autoimmune myositis
Characteristics of muscle weakness (3)
Muscle weakness in autoimmune myositis is symmetrical, diffuse, proximal
Autoimmune myositis
Characteristics of dermatomyositis (5)
Gottron's papules - scaly rash over MTP joints Heliotrope rash Shawl's sign Nail fold erythema Subcut calcifications
Autoimmune myositis
Investigations [4]
Muscle enzymes: CK, AST, ALT, LDH, aldolase (elevated)
Immunology: ANA (+ve), anti-Jo1 antibodies (+ve)
EMG: characteristic fibrillation potentials
Muscle biopsy: confirms dx and excl. other dx
MRI: oedema in acute myositis
Giant cell arteritis
ACR criteria for classification for GCA
What are the 5 criteria
- Age at onset 50 years or more
- New onset localized headache - unilateral
- Temporal artery tenderness - reduced pulsation
- ESR more or equal to 50
- Abnormal temporal biopsy
Giant cell arteritis: Treatment [3]
prednisolone + low dose aspirin
methylprednisolone - 20% stronger
Complications of giant cell arteritis
Loss of vision - irreversible
Autoimmune myositis complications (2)
Cancer
-May be paraneoplastic phenomenon so screen for cancers
Interstitial lung disease
Name 4 neurological features of SLE as part of its classification
Seizures, psychosis, myelitis, peripheral neuropathy
Lab criteria for SLE as part of its classification
ANA □ Anti-dsDNA □ Anti-Sm □ Low complement □ APS Positive DCT
Two other investigations to do for SLE
ESR high, CRP normal
BP
Drug induced lupus
Which organ systems are more commonly involved? [2]
Skin and lung signs are more common
Renal and CNS rarely affected
Management SLE [6]
High factor sunblock Hydroxychloroquine Topical steroids NSAIDs unless renal disease Steroid sparing agents Biologic
Management SLE
Name 3 steroid sparing agents
Name 1 biologic used in maintenance
4 Rx for severe flares
Azathioprine Methotrexate Mycophenolate Biologic: belimumab Severe flares: - Urgent high dose steroids - Mycophenolate - Rituximab - Cyclophosphamide
Management of lupus nephritis [3]
Steroid sparing agents - step up
Renal replacement therapy
Renal transplant
Mixed CTD
Lab test [1]
Anti-u1RNP
APS Recurrent miscarriages are a common feature Autoabs to test for [3] CLOT Rx [1]
Anti-cardiolipin ab, lupus anticoagulant ab, anti-beta2 glycoprotein1
Coagulation defect
Livedo reticularis
Obstetric - recurrent misc
Thrombocytopenia
Rx: lifelong warfarin + aspirin
Autoimmune myositis mx [3]
Prednisolone
Hydroxychloroquine
Topical tacrolimus
