Sensory Motor Neuropathy Complete Antibody Panel (Quest)
Sensory-motor neuropathies may occur by various mechanisms. These include development of autoantibodies to neuronal structures such as myelin associated glycoprotein (MAG) antibody, Hu antibody, and the ganglioside antibodies.
Sensory-motor neuropathies may also occur via antibody cross-reactivity or local immune complex deposition as seen in autoimmune disease with primarily non-neuronal targets including Sjogren's syndrome (SSA/SSB), systemic lupus erythematosus and related conditions (ANA IFA), celiac disease (tTG antibody), vasculitis (ANCA), and immune complex deposition (cryoglobulins, rheumatoid factor). Motor-sensory neuropathy may be associated with monoclonal gammopathy (serum immunofixation and serum immunoglobulins).
ANCA SCREEN / Lab ANCA InterpretationOptimal range: 0 - 0 %
ANCA Screen includes evaluation for p-ANCA, c-ANCA and atypical p-ANCA. A positive ANCA screen reflexes to titer and pattern(s), e.g., cytoplasmic pattern (c-ANCA), perinuclear pattern (p-ANCA), or atypical p-ANCA pattern. c-ANCA and p-ANCA are observed in vasculitis, whereas atypical p-ANCA is observed in IBD (Inflammatory Bowel Disease). Atypical p-ANCA is detected in about 55% to 80% of patients with ulcerative colitis but only 5% to 25% of patients with Crohn's disease.LEARN MORE
CRYOGLOBULIN, QLOptimal range: 0 - 0 %
Cryoglobulins are circulating proteins, specifically immunoglobulins (i.e., IgG, IgM, IgA or light chains), that clump together (precipitate) when they are exposed to cold and dissolve when warmed. They may be present in small quantities in the blood of some healthy people but are most frequently associated with abnormal protein production and a variety of diseases and conditions. This test detects and measures the relative quantity of cryoglobulins in the blood.LEARN MORE
HU AB SCREEN, IFA, SERUMOptimal range: 0 - 0 %
Neuronal nuclear (Hu) antibody is present in patients with various neurological symptoms including two paraneoplastic syndromes: sensory neuropathy (PSN) and encephalomyelitis (PEM). The presence of Hu antibody strongly suggests underlying small cell lung carcinoma (SCLC). Hu antibody is identified by IFA and confirmed by Western Blot. A negative result does not exclude the possibility of a SCLC or other malignant tumor.LEARN MORE
MAG AB (IGM), WESTERN BLOTOptimal range: 0 - 0 %
MAG, Western Blot with reflexes is useful in detecting antibodies associated with autoimmune peripheral neuropathy.
MAG stands for Myelin Associated Glycoprotein.LEARN MORE
MYELOPEROXIDASE ANTIBODYOptimal range: 0 - 1 AI
Autoantibodies to myeloperoxidase (MPO) are commonly associated with the following small-vessel vasculitides:
- microscopic polyangiitis,
- polyarteritis nodosa,
- Churg-Strauss syndrome,
- necrotizing and crescentic glomerulonephritis
- and occasionally granulomatosis with polyangiitis (GPA, Wegener's).
The perinuclear IFA pattern, (p-ANCA) is based largely on autoantibody to myeloperoxidase which serves as the primary antigen. These autoantibodies are present in active disease.LEARN MORE
PROTEINASE-3 ANTIBODYOptimal range: 0 - 1 AI
Autoantibodies to proteinase-3 (PR-3) are accepted as characteristic for granulomatosis with polyangiitis (GPA, Wegener's), and are detectable in 95% of the histologically proven cases. The cytoplasmic IFA pattern, (c-ANCA), is based largely on autoantibody to PR-3 which serves as the primary antigen. These autoantibodies are present in active disease.LEARN MORE
TISSUE TRANSGLUTAMINASE AB, IGAOptimal range: 0 - 4 U/mL
A tissue transglutaminase (tTG) IgA and/or IgG test is used as part of an evaluation for certain autoimmune conditions, most notably celiac disease.
An autoimmune disease can occur when the body’s immune system mistakenly perceives a nonthreatening substance. In the case of people with celiac disease, gluten (a protein found in wheat, barley, rye, and oats) is seen as a foreign invader and is attacked by the immune system. This immune system response in celiac disease also involves the production of antibodies directed against an enzyme normally present in the intestines called tissue transglutaminase (tTG).LEARN MORE
TISSUE TRANSGLUTAMINASE AB, IGGOptimal range: 0 - 0 %
Tissue transglutaminase has been identified as the major autoantigen in celiac disease. IgA antibodies against tTG are highly disease specific serological markers for celiac disease and dermatitis herpetiformis. tTG IgG antibodies are less specific for these diseases but are helpful markers in patients with IgA deficiency.
A negative tTG IgG test alone does not rule out gluten-sensitive enteropathy.
Celiac disease is a life-long condition in which ingestion of gluten, the water insoluble wheat-gliadin and the prolamins in rye and barley, leads to chronic inflammation and damage of the small intestinal mucosa. Also useful in monitoring adherence to gluten-free diet in patients with IgA deficiency.
TTGA and TTGG both >10 U/mL: Suggestive of Celiac disease
TTG-IgG may be used to follow patients with Celiac disease who are IgA deficient. However, TTG-IgG alone is not sufficient to diagnose Celiac Disease.LEARN MORE