Autoantibodies Test Flashcards
RhF - Rheumatoid factor
Sjögren's 100% Felty's syndrome 100% (rheumatoid arthritis, splenomegaly, leukopenia) RA 70% Infection 50% Mixed connective tissue disease 50% SLE 40% Systemic sclerosis 30%
Anti CCP - anticyclic citrullinated peptide Ab
Rheumatoid arthritis RA 96% specificity
ANA - antinuclear antibody (positive by immunofluorescence)
SLE >95%
Autoimmune hepatitis 75%
Sjögren’s 68%
RA 30%
What is the pattern of staining for ANA in different diseases?
Homogenous - SLE
Speckled - Mixed connective tissue disease
Nucleolar - Systemic sclerosis
Contromere - Limited (cutaneous) systemic sclerosis
anti dsDNA - double stranded DNA
SLE - 60% sensitive but highly specific
Antihistone Ab
Drug induced SLE - around 100%
Examples: Isoniazid, hydralazine (in slow acetylators), procainamide, quinidine, chlorpromazine, minocycline, phenytoin.
Skin and lung signs prevail, disease remits if drug is stopped.
Sulphonamides and OCP may worsen idiopathic SLE
Antiphospholipid Ab
Antiphospholipid syndrome, SLE
Anticentromere Ab
Limited (cutaneous) systemic sclerosis (CREST syndrome) 70-80% C - Calcinosis (subcutaneous tissue) R - Reynaud's E - oEsophageal and gut dysmotility S - Sclerodactyly T - Telangectasia
Skin involvement is limited to the hands face and feet
Pulmonary hypertension is often present subclinically and can progress rapidly - treat with sildenafil, bosentan
Anti ENA - Extractable nuclear antigen Ab
Anti-Ro: SLE, Sjögren’s, systemic sclerosis (associated with congenital heart block)
Anti-La: Sjögren’s, SLE (15%)
Anti-Sm: SLE (20-30%)
Anti-RNP: SLE, mixed connective tissue disorder
Anti-Jo / Mi-2: Polymyositis, dermatomyositis
Anti-Scl70 (topoisomerase-1): Diffuse systemic sclerosis
AMA - Antimitochondrial Ab
Primary biliary sclerosis 95%
Autoimmune hep 30%
SMA - anti-smooth muscle Ab
Autoimune Hepatitis 70%
Primary Biliary Sclerosis 50%
Gastri parietal cell Ab
Pernicious anaemia 90%
Atrophic gastritis 40%
“Normal” 10%
Intrinsic Factor Ab
Pernicious anaemia 50%
Alpha-gliadin, antitissue transglutaminase, anti-endomysial Abs
Ceoliac disease
Thyroid Peroxidase Ab
Hashimoto’s thyroiditis 87%
Grave’s 50%
