08-31-2008, 10:39 PM
i Found this to be one of the best collections of all the Anti-__ Antibody lists. Not meant as a full review to read, but a good text file to hand on hand:
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The anti-microsomal antibody or microsomal antibody test is used to diagnose conditions such as Hashimoto's thyroiditis and other autoimmune disorders.
CONNECTIVE TISSUE DISEASE
Anti cardiolipin antibody (ß2 glycoprotein 1)
Anti cardiolipin antibodies form part of a spectrum of anti phospholipid antibodies including anti ß2 glycoprotein 1 antibody. They are found in patients with the anti-phospholipid syndrome (APS) which may be primary or occur as a secondary complication of SLE. The major features of APS are thromboses (arterial or venous), thrombocytopenia, recurrent spontaneous abortion, skin rash (livedo reticularis). Patients with APS may also have detectable lupus anticoagulant and all patients suspected of this condition should have a sample sent to Haematology for coagulation studies.
Results reported in IgG or IgM phospholipid units, Positive values >10 GPLU and >7 MPLU.
Anti centromere antibody
These antibodies are found in patients with the CREST variant of scleroderma (Calcinosis, Raynaud™s, oEsophageal immotility, Sclerodactyly, Telangiectasia) and in patients with limited cutaneous scleroderma. Also found in up to 12% of patients with primary biliary cirrhosis, over half of such patients have clinical signs of scleroderma.
Results reported as positive or negative.
Anti ds DNA antibody
Anti-dsDNA antibodies are strongly suggestive of systemic lupus erythematosus (SLE) although they are present in only 40-70% of patients with this disease. Our present anti dsDNA profile includes two assays for dsDNA.
(i)The ELISA dsDNA assay. This assay is a good screening test with high sensitivity but poor specificity.
(ii)The Crithidia dsDNA assay. This assay is performed on samples which are positive with ELISA assay. The assay has very high specificity but poor sensitivity for SLE. These two assays can give differing results, please contact laboratory for interpretation.
Anti dsDNA antibody (ELISA):Results reported in mg/L, positive value >35 mg/L.
Anti dsDNA antibody (Crithidia):Results reported as positive or negative.
Anti Extractable Nuclear Antigen antibody screen (ENA)
Anti ENA antibodies are useful in classifying clinical subsets of connective tissue diseases. Six major specificities are tested in this screen, each with different disease associations. Samples positive for nuclear antibodies on the autoantibody screen are tested for these six antibodies. See below.
Anti Ribonucleoprotein (RNP) antibodies
Antibodies to RNP (ribonucleoprotein) occur in patients with SLE and mixed connective tissue disease (MCTD).
Results reported as positive or negative.
Anti Sm antibody
Anti Sm antibodies are very specific for a diagnosis of SLE, occurring in 25-30% of Afro-Caribbean patients but in a much lower proportion of Caucasian patients. Usually found in association with anti RNP antibody.
Results reported as positive or negative.
Anti Ro (SS-A) antibody
Anti Ro antibodies are found in patients with primary Sjogren™s syndrome, subacute cutaneous lupus erythematosus (particularly photosensitivity), neonatal lupus, congenital complete heart block in babies born to SLE mothers (rare) and SLE with interstitial pneumonitis.
Result reported as positive or negative.
Anti La (SS-B) antibody
Anti La antibodies are detected in patients with primary Sjogren™s syndrome and SLE.
Results reported as positive or negative.
Anti Jo-1 (histidyl tRNA synthetase) antibody
Anti Jo-1 antibodies are found in 20-40% of patients with aggressive polymyositis usually in association with interstitial lung disease and arthralgia. Antibodies to other tRNA synthetases are also associated with variant myositis syndromes.
Results reported as positive or negative.
Anti Scl-70 (topoisomerase-1) antibody
These antibodies are detected in 20-40% of patients with progressive systemic sclerosis and 20% of patients with limited scleroderma. Such patients are more likely to develop facial skin rash and heart involvement.
Results reported as positive or negative.
Anti histone antibody
Anti histone antibodies are found in 18-50% of patients with SLE and in 95% of patients with drug induced SLE. This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield.
Results reported asunits / ml, positive >5 U/ml.
Anti nuclear antibodies
Antinuclear antibodies are associated with various autoimmune diseases (especially rheumatological diseases) and are detected using a number of various techniques.
Anti nuclear antibody (ANA)
These antibodies are present in elevated titres (> 80) in > 95% of untreated cases of systemic lupus erythematosus (SLE). The absence of an ANA virtually excludes this diagnosis. ANA may also occur in a number of other conditions including juvenile chronic arthritis, Sjogren™s syndrome, fibrosing alveolitis, chronic active hepatitis (CAH), viral infections particularly EBV and CMV and in drug reactions. Low titre ANA are detected at increasing frequency in normal individuals with increasing age. Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti nuclear antibody (speckled pattern)
Speckled anti nuclear antibodies are found in patients with SLE, mixed connective tissue disease (MCTD), Sjogren™s syndrome and scleroderma. They are associated with antibodies to ENA. Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti nucleolar antibody
These antibodies are typically found in patients with scleroderma, SLE and polymyositis.
Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti ribosome antibody
These antibodies are found in 10-15% of patients with SLE, often in the absence of antibodies to dsDNA, they can also be found in patients with rheumatoid arthritis. Also associated with neuropsychiatric symptoms and renal involvement. Antibody levels correlate with disease activity. Antibody detected on autoantibody screen. Results reported as titre, positive titre >40.
All sera positive at >40 for above nuclear antibodies are further tested for antibodies to dsDNA and ENA (RNP, Sm, Ro, La, Jo-1, Scl-70)
Anti PM-1 / Anti Mi-2 / anti SRP antibodies.
Anti PM-1 antibodies are found in patients with the polymyositis/scleroderma overlap syndrome. Anti Mi-2 antibodies are found in patients with dermatomyositis and anti SRP (signal recognition particle) antibodies are found in patients with polymyositis and dermatomyositis.
Results reported as positive or negative.
Rheumatoid factor (RF)
Indicated in the investigation of inflammatory arthropathies. High levels are associated with rheumatoid arthritis especially extra - articular manifestations e.g. vasculitis and nodules. RF is not of value in laboratory monitoring of disease activity, Low titre RFs may occur in other connective tissue /autoimmune diseases, SLE, CAH, scleroderma and in response to infection.
Results reported in International unit/ml, positive >25 IU/ml.
Anti CCP Antibodies
Measurement of anti-cyclic citrullinated protein (CCP) antibodies is useful in predicting future development of RA in patients with undifferentialed arthritis. The test has enhanced specificity and positive predictive value compared with rheumatoid factor measurement.
Results reported as U/ml. Positive value > 10.
GASTROINTESTINAL DISEASE
Coeliac disease antibody screen
Requests for coeliac disease antibodies are screened for IgA anti tissue transglutaminase antibody, those positive are further tested for IgA anti endomysial antibody. For diagnostic purposes these samples should be from patients taking a gluten containing diet for at least 4 weeks. Tests for IgG transglutaminase and endomysial antibodies are performed on samples from patients with suspected coeliac disease with IgA deficiency.
Anti tissue transglutaminase antibodies
Tissue transglutaminase is the antigenic target for anti endomysial antibody and these IgA class antibodies are tested in combination with anti endomysial antibodies bringing the sensitivity for coeliac disease to nearly 100%. Treatment with a gluten free diet leads to gradual disappearance of these antibodies. They can also be used to monitor dietary compliance. Approx 10% of coeliac patients are only positive for either endomysial or transglutaminase antibodies. IgG class tissue transglutaminase antibodies maybe detected in IgA deficient patients with coeliac disease
Results reported in ELISA units, positive IgA TGA >15 EU/ml, positive IgG TGA >15 EU/ml.
Anti endomysial antibodies (EMA)
These IgA class antibodies are very specific (90-100%) for coeliac disease (CD) and dermatitis herpetiformis (DH). Treatment with a gluten free diet leads to gradual disappearance of these antibodies. They can also be used to monitor dietary compliance. IgG class anti endomysial antibodies maybe detected in IgA deficient patients with coeliac disease.
Results reported as positive or negative.
Anti gastric parietal cell (GPC) antibodies
Anti GPC antibodies are present in 95% of patients with pernicious anaemia in the early stages and in patients with atrophic gastritis (type A). They are also associated with other organ specific autoimmune diseases especially autoimmune thyroid disease. Also found in the normal population (the incidence rising with increasing age). Anti-intrinsic factor antibody is a better confirmatory test for pernicious anaemia.
Antibody detected on autoimmune screen.
Results reported as a titre, positive titre >40.
Anti gliadin antibody
IgA class antigliadin antibodies are also associated with coeliac disease, dermatitis herpetiformis and gluten sensitivity. They are not part of the coeliac disease screen as specificity is low, as they are also detected in a wide range of other clinical conditions. Useful in the diagnosis of children with coeliac disease where anti endomysial antibodies may be negative. This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield.
Results reportedas positive or negative.
Anti intrinsic factor antibodies (IFA)
Anti IFA antibodies are highly specific for pernicious anaemia and are found in up to 75% of patients. Highly specific if found in combination with gastric parietal cell antibody. Anti-intrinsic factor antibody may be detected before anaemia develops.
Results reported in Relative units /ml, positive >20 RU/ml.
Anti liver kidney antibodies (LKM)
Anti LKM-1 antibodies are associated with patients with type 2a and 2b autoimmune hepatitis. This is the most common form of CAH in childhood and has a particularly poor prognosis and can be associated with hepatitis C infection. Anti LKM-2 antibody is associated with drug induced hepatitis and LKM-3 antibody is associated with hepatitis D infection. Antibody detected on autoantibody screen.
Results reported as titre, positive >40.
Anti mitochondrial antibody (M2)
Anti M2 mitochondrial antibodies are detected at high titre in 95% of patients with primary biliary cirrhosis. They can also be found in patients (usually lower titres) with chronic active hepatitis, autoimmune thyroiditis and Sjogrens syndrome.
Other subtypes of mitochondrial antibodies have been described such as M1: associated with positive syphilis serology and M5: associated with SLE and the antiphospholipid syndrome. Antibody detected on autoimmune screen.
Results reported as a titre, positive >40.
Anti smooth muscle antibody
These antibodies can occur in high titres in patients with autoimmune hepatitis. Low titre antibodies may be detected after infection.
Antibody detected on autoantibody screen.
Results reported as titre, positive >40.
ENDOCRINE DISEASE
Anti adrenal antibodies
These antibodies are detected in 60-70% of patients with idiopathic Addison™s disease.
Results reported as negative or positive (with titre).
Anti islet cell antibodies
These antibodies are found early in the course of type I diabetes mellitus, gradually disappear with time. Not found in type II diabetes mellitus.
Results reported as negative or positive (with titre).
Anti steroid cell antibodies
Number of antibodies reacting with cytochrome P450 enzymes in adrenal cortex, various cell types within the ovary and testes and the anterior pituitary. Antibodies found in patients with Type 1 autoimmune polyendocrinopathy syndrome and premature gonadal and ovarian failure.
Results reported as negative or positive (with titre).
Anti thyroperoxidase (TPO) antibody
These antibodies are found in patients with primary myxoedema, Hashimoto™s thyroiditis and Graves™ disease. Also found in patients with other organ specific autoimmune diseases such as pernicious anaemia, Addisons disease. Positivity may be predictive of future autoimmune thyroid disease. Clinical and biochemical follow-up is advised.
Results reported as IU/ml, positive >135 IU/ml.
Anti TSH receptor antibodies
These antibodies, to thyroid stimulating hormone receptor (stimulating and blocking), are strongly associated with Graves™ disease and rarely occur in other types of thyroid disease.This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield..
Results for both types of antibody are reported as positive or negative.
NEUROLOGICAL DISEASE
Anti acetyl choline receptor antibody (AChR).
These antibodies are found in 85 “ 90% of patients with myasthenia gravis. 10-15% of patients are sero-negative. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported as antibody concentration.
< 5x10 -10 M: negative: >5x10 -10 M: positive
Anti ganglioside antibodies (GM1, GQ1b).
These antibodies are associated with a number of peripheral neuropathies. Anti GM1 antibodies are associated with Guillain Barré syndrome (GBS), chronic demyelinating polyneuropathy and multifocal motor neuropathy. Anti GQ1b antibodies are associated with Miller Fisher variant of GBS. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Anti ganglioside GM1 antibody: Results reported in units, normal range 0-200.
Anti ganglioside GQ1b antibody. Results reported in units, normal range 0-25.
Anti glutamic acid decarboxylase (GAD) antibodies.
These antibodies are found in >60% of patients with the stiff man syndrome and also in patients with type 1 diabetes mellitus. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported as U/ml, normal range 0-1 U/ml.
Anti muscle specific kinase antibody (MuSK).
These antibodies are found in approx 40% of patients with generalised myasthenia gravis who are negative for anti AChR antibody. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results are reported as positive or negative.
Anti paraneoplastic antibodies (neuronal nuclear and purkinje cell).
These antibodies are associated with paraneoplastic disorders with accompanying carcinomas. They include anti Yo (PCCA), anti Hu (ANNA-1) and anti Ri (ANNA-2) antibodies. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results are reported as positive or negative.
Anti skeletal muscle antibody.
These antibodies are present in some patients with myasthenia gravis and almost all (80 “ 100%) patients with thymomatous myasthenia gravis. They can also occur in patients with hepatitis, acute viral infections and polymyositis.
Results reported as titre, positive >10.
Anti voltage gated calcium channel antibody (VGCC).
These antibodies are found in patients with the Lambert-Eaton myasthenic syndrome (LEMS). This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported in pM, positive >45pM.
Anti voltage gated potassium channel antibody (anti VKCC ab).
These antibodies are associated with acquired neuromyotonia. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported in pM, positive >100pM.
RENAL DISEASE ASSOCIATED ANTIBODIES
C3 nephritic factor (C3 Nef)
These antibodies, to the alternative pathway C3 convertase, are found in patients with membrano-proliferative glomerulonephritis (type II) and partial lipodystrophy.
Results reported as detected or not detected.
Anti glomerular basement membrane antibodies (GBM)
These antibodies are found in patients with Goodpasture™s syndrome (>90% sensitivity)
Results reported in units, positive value >10 EU/ml.
Anti neutrophil cytoplasmic antibodies (ANCA)
Indicated in the investigation of primary systemic vasculitis. Assay should be restricted to the investigation of patients suspected of primary systemic vasculitis.
Three main patterns are recognised, cytoplasmic (C-ANCA), perinuclear (P-ANCA) and atypical ANCA. C-ANCA with specificity for proteinase-3 (PR-3) has a high predictive value for active generalised Wegener™s granulomatosis (WG) and can also be found in patients with microscopic polyangiitis. P-ANCA with anti-myeloperoxidase (MPO-ANCA) specificity is predictive for patients with active microscopic polyangiitis and other forms of severe vasculitis, some patients with WG also have this antibody.
P-ANCA with specificities other than MPO-ANCA occur in some patients with inflammatory bowel disease, sclerosing cholangitis, rheumatoid arthritis, systemic lupus erythematosus, chronic active hepatitis and other autoimmune diseases. In such patients, ANCA levels are often low and of uncertain significance.
Atypical ANCA are found in some cases of drug induced vasculitis but otherwise are of uncertain clinical significance
Results reported as a titre, positive titre >20.
All positive ANCA are tested for specificity to PR3-ANCA and MPO-ANCA
Anti Proteinase-3 antibody (PR3)
Proteinase 3 (PR3) is the major target antigen for C-ANCA. The detection of anti PR3-ANCA has a high predictive value for Wegener™s granulomatosis.
Results reported in ELISA units/ml, positive value >2 U/ml.
Anti Myeloperoxidase antibody (MPO)
Myeloperoxidase is the target antigen for the majority of P-ANCA and is associated with microscopic polyangiitis.
Result reported in ELISA units/ml, positive value >6 U/ml.
OTHER AUTOANTIBODIES
Anti C1q antibodies
Antibodies to C1q may be associated with renal disease activity in patients with SLE. High levels are found in patients with hypocomplementaemic urticarial vasculitis syndrome (HUVS). These assays are performed by the Supraregional Protein Reference Laboratory, Sheffield .
Results reported as ELISA U/ml, positive value >15 U/ml.
Anti-cardiac muscle antibody
These antibodies are found in some patients with Dressler's syndrome and post cardiotomy syndrome
Results reported as negative or positive (with titre).
Anti-IgA antibodies
These antibodies may occur in patients with selective IgA deficiency. They can cause blood product transfusion reactions. These assays are performed by The Immunology Dept., John Radcliffe Hospital, Sheffield.
Results reported as a titre
Skin reactive antibodies
Two antibodies recognised: (i) Anti-intercellular substance / desmosome antibodies are found in patients with all forms of pemphigus. The antibody level is related to disease activity and therefore is useful in monitoring treatment. (ii) Anti-basement membrane zone antibodies are found in patients with bullous pemphigoid.
Results reported as negative or positive (with titre).
Other autoantibodies are available on request: Please contact the laboratory.
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The anti-microsomal antibody or microsomal antibody test is used to diagnose conditions such as Hashimoto's thyroiditis and other autoimmune disorders.
CONNECTIVE TISSUE DISEASE
Anti cardiolipin antibody (ß2 glycoprotein 1)
Anti cardiolipin antibodies form part of a spectrum of anti phospholipid antibodies including anti ß2 glycoprotein 1 antibody. They are found in patients with the anti-phospholipid syndrome (APS) which may be primary or occur as a secondary complication of SLE. The major features of APS are thromboses (arterial or venous), thrombocytopenia, recurrent spontaneous abortion, skin rash (livedo reticularis). Patients with APS may also have detectable lupus anticoagulant and all patients suspected of this condition should have a sample sent to Haematology for coagulation studies.
Results reported in IgG or IgM phospholipid units, Positive values >10 GPLU and >7 MPLU.
Anti centromere antibody
These antibodies are found in patients with the CREST variant of scleroderma (Calcinosis, Raynaud™s, oEsophageal immotility, Sclerodactyly, Telangiectasia) and in patients with limited cutaneous scleroderma. Also found in up to 12% of patients with primary biliary cirrhosis, over half of such patients have clinical signs of scleroderma.
Results reported as positive or negative.
Anti ds DNA antibody
Anti-dsDNA antibodies are strongly suggestive of systemic lupus erythematosus (SLE) although they are present in only 40-70% of patients with this disease. Our present anti dsDNA profile includes two assays for dsDNA.
(i)The ELISA dsDNA assay. This assay is a good screening test with high sensitivity but poor specificity.
(ii)The Crithidia dsDNA assay. This assay is performed on samples which are positive with ELISA assay. The assay has very high specificity but poor sensitivity for SLE. These two assays can give differing results, please contact laboratory for interpretation.
Anti dsDNA antibody (ELISA):Results reported in mg/L, positive value >35 mg/L.
Anti dsDNA antibody (Crithidia):Results reported as positive or negative.
Anti Extractable Nuclear Antigen antibody screen (ENA)
Anti ENA antibodies are useful in classifying clinical subsets of connective tissue diseases. Six major specificities are tested in this screen, each with different disease associations. Samples positive for nuclear antibodies on the autoantibody screen are tested for these six antibodies. See below.
Anti Ribonucleoprotein (RNP) antibodies
Antibodies to RNP (ribonucleoprotein) occur in patients with SLE and mixed connective tissue disease (MCTD).
Results reported as positive or negative.
Anti Sm antibody
Anti Sm antibodies are very specific for a diagnosis of SLE, occurring in 25-30% of Afro-Caribbean patients but in a much lower proportion of Caucasian patients. Usually found in association with anti RNP antibody.
Results reported as positive or negative.
Anti Ro (SS-A) antibody
Anti Ro antibodies are found in patients with primary Sjogren™s syndrome, subacute cutaneous lupus erythematosus (particularly photosensitivity), neonatal lupus, congenital complete heart block in babies born to SLE mothers (rare) and SLE with interstitial pneumonitis.
Result reported as positive or negative.
Anti La (SS-B) antibody
Anti La antibodies are detected in patients with primary Sjogren™s syndrome and SLE.
Results reported as positive or negative.
Anti Jo-1 (histidyl tRNA synthetase) antibody
Anti Jo-1 antibodies are found in 20-40% of patients with aggressive polymyositis usually in association with interstitial lung disease and arthralgia. Antibodies to other tRNA synthetases are also associated with variant myositis syndromes.
Results reported as positive or negative.
Anti Scl-70 (topoisomerase-1) antibody
These antibodies are detected in 20-40% of patients with progressive systemic sclerosis and 20% of patients with limited scleroderma. Such patients are more likely to develop facial skin rash and heart involvement.
Results reported as positive or negative.
Anti histone antibody
Anti histone antibodies are found in 18-50% of patients with SLE and in 95% of patients with drug induced SLE. This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield.
Results reported asunits / ml, positive >5 U/ml.
Anti nuclear antibodies
Antinuclear antibodies are associated with various autoimmune diseases (especially rheumatological diseases) and are detected using a number of various techniques.
Anti nuclear antibody (ANA)
These antibodies are present in elevated titres (> 80) in > 95% of untreated cases of systemic lupus erythematosus (SLE). The absence of an ANA virtually excludes this diagnosis. ANA may also occur in a number of other conditions including juvenile chronic arthritis, Sjogren™s syndrome, fibrosing alveolitis, chronic active hepatitis (CAH), viral infections particularly EBV and CMV and in drug reactions. Low titre ANA are detected at increasing frequency in normal individuals with increasing age. Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti nuclear antibody (speckled pattern)
Speckled anti nuclear antibodies are found in patients with SLE, mixed connective tissue disease (MCTD), Sjogren™s syndrome and scleroderma. They are associated with antibodies to ENA. Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti nucleolar antibody
These antibodies are typically found in patients with scleroderma, SLE and polymyositis.
Antibody detected on autoantibody screen.
Results reported as titre, positive titre >40.
Anti ribosome antibody
These antibodies are found in 10-15% of patients with SLE, often in the absence of antibodies to dsDNA, they can also be found in patients with rheumatoid arthritis. Also associated with neuropsychiatric symptoms and renal involvement. Antibody levels correlate with disease activity. Antibody detected on autoantibody screen. Results reported as titre, positive titre >40.
All sera positive at >40 for above nuclear antibodies are further tested for antibodies to dsDNA and ENA (RNP, Sm, Ro, La, Jo-1, Scl-70)
Anti PM-1 / Anti Mi-2 / anti SRP antibodies.
Anti PM-1 antibodies are found in patients with the polymyositis/scleroderma overlap syndrome. Anti Mi-2 antibodies are found in patients with dermatomyositis and anti SRP (signal recognition particle) antibodies are found in patients with polymyositis and dermatomyositis.
Results reported as positive or negative.
Rheumatoid factor (RF)
Indicated in the investigation of inflammatory arthropathies. High levels are associated with rheumatoid arthritis especially extra - articular manifestations e.g. vasculitis and nodules. RF is not of value in laboratory monitoring of disease activity, Low titre RFs may occur in other connective tissue /autoimmune diseases, SLE, CAH, scleroderma and in response to infection.
Results reported in International unit/ml, positive >25 IU/ml.
Anti CCP Antibodies
Measurement of anti-cyclic citrullinated protein (CCP) antibodies is useful in predicting future development of RA in patients with undifferentialed arthritis. The test has enhanced specificity and positive predictive value compared with rheumatoid factor measurement.
Results reported as U/ml. Positive value > 10.
GASTROINTESTINAL DISEASE
Coeliac disease antibody screen
Requests for coeliac disease antibodies are screened for IgA anti tissue transglutaminase antibody, those positive are further tested for IgA anti endomysial antibody. For diagnostic purposes these samples should be from patients taking a gluten containing diet for at least 4 weeks. Tests for IgG transglutaminase and endomysial antibodies are performed on samples from patients with suspected coeliac disease with IgA deficiency.
Anti tissue transglutaminase antibodies
Tissue transglutaminase is the antigenic target for anti endomysial antibody and these IgA class antibodies are tested in combination with anti endomysial antibodies bringing the sensitivity for coeliac disease to nearly 100%. Treatment with a gluten free diet leads to gradual disappearance of these antibodies. They can also be used to monitor dietary compliance. Approx 10% of coeliac patients are only positive for either endomysial or transglutaminase antibodies. IgG class tissue transglutaminase antibodies maybe detected in IgA deficient patients with coeliac disease
Results reported in ELISA units, positive IgA TGA >15 EU/ml, positive IgG TGA >15 EU/ml.
Anti endomysial antibodies (EMA)
These IgA class antibodies are very specific (90-100%) for coeliac disease (CD) and dermatitis herpetiformis (DH). Treatment with a gluten free diet leads to gradual disappearance of these antibodies. They can also be used to monitor dietary compliance. IgG class anti endomysial antibodies maybe detected in IgA deficient patients with coeliac disease.
Results reported as positive or negative.
Anti gastric parietal cell (GPC) antibodies
Anti GPC antibodies are present in 95% of patients with pernicious anaemia in the early stages and in patients with atrophic gastritis (type A). They are also associated with other organ specific autoimmune diseases especially autoimmune thyroid disease. Also found in the normal population (the incidence rising with increasing age). Anti-intrinsic factor antibody is a better confirmatory test for pernicious anaemia.
Antibody detected on autoimmune screen.
Results reported as a titre, positive titre >40.
Anti gliadin antibody
IgA class antigliadin antibodies are also associated with coeliac disease, dermatitis herpetiformis and gluten sensitivity. They are not part of the coeliac disease screen as specificity is low, as they are also detected in a wide range of other clinical conditions. Useful in the diagnosis of children with coeliac disease where anti endomysial antibodies may be negative. This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield.
Results reportedas positive or negative.
Anti intrinsic factor antibodies (IFA)
Anti IFA antibodies are highly specific for pernicious anaemia and are found in up to 75% of patients. Highly specific if found in combination with gastric parietal cell antibody. Anti-intrinsic factor antibody may be detected before anaemia develops.
Results reported in Relative units /ml, positive >20 RU/ml.
Anti liver kidney antibodies (LKM)
Anti LKM-1 antibodies are associated with patients with type 2a and 2b autoimmune hepatitis. This is the most common form of CAH in childhood and has a particularly poor prognosis and can be associated with hepatitis C infection. Anti LKM-2 antibody is associated with drug induced hepatitis and LKM-3 antibody is associated with hepatitis D infection. Antibody detected on autoantibody screen.
Results reported as titre, positive >40.
Anti mitochondrial antibody (M2)
Anti M2 mitochondrial antibodies are detected at high titre in 95% of patients with primary biliary cirrhosis. They can also be found in patients (usually lower titres) with chronic active hepatitis, autoimmune thyroiditis and Sjogrens syndrome.
Other subtypes of mitochondrial antibodies have been described such as M1: associated with positive syphilis serology and M5: associated with SLE and the antiphospholipid syndrome. Antibody detected on autoimmune screen.
Results reported as a titre, positive >40.
Anti smooth muscle antibody
These antibodies can occur in high titres in patients with autoimmune hepatitis. Low titre antibodies may be detected after infection.
Antibody detected on autoantibody screen.
Results reported as titre, positive >40.
ENDOCRINE DISEASE
Anti adrenal antibodies
These antibodies are detected in 60-70% of patients with idiopathic Addison™s disease.
Results reported as negative or positive (with titre).
Anti islet cell antibodies
These antibodies are found early in the course of type I diabetes mellitus, gradually disappear with time. Not found in type II diabetes mellitus.
Results reported as negative or positive (with titre).
Anti steroid cell antibodies
Number of antibodies reacting with cytochrome P450 enzymes in adrenal cortex, various cell types within the ovary and testes and the anterior pituitary. Antibodies found in patients with Type 1 autoimmune polyendocrinopathy syndrome and premature gonadal and ovarian failure.
Results reported as negative or positive (with titre).
Anti thyroperoxidase (TPO) antibody
These antibodies are found in patients with primary myxoedema, Hashimoto™s thyroiditis and Graves™ disease. Also found in patients with other organ specific autoimmune diseases such as pernicious anaemia, Addisons disease. Positivity may be predictive of future autoimmune thyroid disease. Clinical and biochemical follow-up is advised.
Results reported as IU/ml, positive >135 IU/ml.
Anti TSH receptor antibodies
These antibodies, to thyroid stimulating hormone receptor (stimulating and blocking), are strongly associated with Graves™ disease and rarely occur in other types of thyroid disease.This assay is performed by the Supraregional Protein Reference Laboratory, Sheffield..
Results for both types of antibody are reported as positive or negative.
NEUROLOGICAL DISEASE
Anti acetyl choline receptor antibody (AChR).
These antibodies are found in 85 “ 90% of patients with myasthenia gravis. 10-15% of patients are sero-negative. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported as antibody concentration.
< 5x10 -10 M: negative: >5x10 -10 M: positive
Anti ganglioside antibodies (GM1, GQ1b).
These antibodies are associated with a number of peripheral neuropathies. Anti GM1 antibodies are associated with Guillain Barré syndrome (GBS), chronic demyelinating polyneuropathy and multifocal motor neuropathy. Anti GQ1b antibodies are associated with Miller Fisher variant of GBS. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Anti ganglioside GM1 antibody: Results reported in units, normal range 0-200.
Anti ganglioside GQ1b antibody. Results reported in units, normal range 0-25.
Anti glutamic acid decarboxylase (GAD) antibodies.
These antibodies are found in >60% of patients with the stiff man syndrome and also in patients with type 1 diabetes mellitus. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported as U/ml, normal range 0-1 U/ml.
Anti muscle specific kinase antibody (MuSK).
These antibodies are found in approx 40% of patients with generalised myasthenia gravis who are negative for anti AChR antibody. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results are reported as positive or negative.
Anti paraneoplastic antibodies (neuronal nuclear and purkinje cell).
These antibodies are associated with paraneoplastic disorders with accompanying carcinomas. They include anti Yo (PCCA), anti Hu (ANNA-1) and anti Ri (ANNA-2) antibodies. These assays are performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results are reported as positive or negative.
Anti skeletal muscle antibody.
These antibodies are present in some patients with myasthenia gravis and almost all (80 “ 100%) patients with thymomatous myasthenia gravis. They can also occur in patients with hepatitis, acute viral infections and polymyositis.
Results reported as titre, positive >10.
Anti voltage gated calcium channel antibody (VGCC).
These antibodies are found in patients with the Lambert-Eaton myasthenic syndrome (LEMS). This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported in pM, positive >45pM.
Anti voltage gated potassium channel antibody (anti VKCC ab).
These antibodies are associated with acquired neuromyotonia. This assay is performed by The Institute of Molecular Science, John Radcliffe Hospital, Oxford.
Results reported in pM, positive >100pM.
RENAL DISEASE ASSOCIATED ANTIBODIES
C3 nephritic factor (C3 Nef)
These antibodies, to the alternative pathway C3 convertase, are found in patients with membrano-proliferative glomerulonephritis (type II) and partial lipodystrophy.
Results reported as detected or not detected.
Anti glomerular basement membrane antibodies (GBM)
These antibodies are found in patients with Goodpasture™s syndrome (>90% sensitivity)
Results reported in units, positive value >10 EU/ml.
Anti neutrophil cytoplasmic antibodies (ANCA)
Indicated in the investigation of primary systemic vasculitis. Assay should be restricted to the investigation of patients suspected of primary systemic vasculitis.
Three main patterns are recognised, cytoplasmic (C-ANCA), perinuclear (P-ANCA) and atypical ANCA. C-ANCA with specificity for proteinase-3 (PR-3) has a high predictive value for active generalised Wegener™s granulomatosis (WG) and can also be found in patients with microscopic polyangiitis. P-ANCA with anti-myeloperoxidase (MPO-ANCA) specificity is predictive for patients with active microscopic polyangiitis and other forms of severe vasculitis, some patients with WG also have this antibody.
P-ANCA with specificities other than MPO-ANCA occur in some patients with inflammatory bowel disease, sclerosing cholangitis, rheumatoid arthritis, systemic lupus erythematosus, chronic active hepatitis and other autoimmune diseases. In such patients, ANCA levels are often low and of uncertain significance.
Atypical ANCA are found in some cases of drug induced vasculitis but otherwise are of uncertain clinical significance
Results reported as a titre, positive titre >20.
All positive ANCA are tested for specificity to PR3-ANCA and MPO-ANCA
Anti Proteinase-3 antibody (PR3)
Proteinase 3 (PR3) is the major target antigen for C-ANCA. The detection of anti PR3-ANCA has a high predictive value for Wegener™s granulomatosis.
Results reported in ELISA units/ml, positive value >2 U/ml.
Anti Myeloperoxidase antibody (MPO)
Myeloperoxidase is the target antigen for the majority of P-ANCA and is associated with microscopic polyangiitis.
Result reported in ELISA units/ml, positive value >6 U/ml.
OTHER AUTOANTIBODIES
Anti C1q antibodies
Antibodies to C1q may be associated with renal disease activity in patients with SLE. High levels are found in patients with hypocomplementaemic urticarial vasculitis syndrome (HUVS). These assays are performed by the Supraregional Protein Reference Laboratory, Sheffield .
Results reported as ELISA U/ml, positive value >15 U/ml.
Anti-cardiac muscle antibody
These antibodies are found in some patients with Dressler's syndrome and post cardiotomy syndrome
Results reported as negative or positive (with titre).
Anti-IgA antibodies
These antibodies may occur in patients with selective IgA deficiency. They can cause blood product transfusion reactions. These assays are performed by The Immunology Dept., John Radcliffe Hospital, Sheffield.
Results reported as a titre
Skin reactive antibodies
Two antibodies recognised: (i) Anti-intercellular substance / desmosome antibodies are found in patients with all forms of pemphigus. The antibody level is related to disease activity and therefore is useful in monitoring treatment. (ii) Anti-basement membrane zone antibodies are found in patients with bullous pemphigoid.
Results reported as negative or positive (with titre).
Other autoantibodies are available on request: Please contact the laboratory.