ANA

• Negative: 0.00 to 1.00 Od ratio
• Positive: more than 1.00 Od ratio

• Anti nuclear antibodies (ANA) are a group of auto antibodies produced by a person’s immune system when it fails to adequately distinguish between self and nonself.

• Anti nuclear antibody is a test done early in the evaluation of a person for auto immune or Rheumatic disease, particularly Systemic lupus erythematosus(SLE). ANA specifically target substances found in the nucleus of a cell, hence the name “Antinuclear”.
• This test is particularly useful when diagnosing a person with symptoms of SLE. If the test is negative, it is unlikely that the person has SLE; if the test is positive more tests are done to confirm whether a person has SLE or another related disease. Other diseases such as scleroderma, Sjogren’s syndrome , Raynauds disease , Rheumatoid Arthritis, Auto immune hepatitis also have a positive test for Anti nuclear antibodies.

ANA is done to

• Diagnose SLE
• Distinguish between SLE and Rheumatoid Arthritis when the diagnosis is unclear
• Diagnose other suspected Auto immune diseases
• Persistently negative ANA tests occur in 5% of SLE patients due to some genetic conditions . Sera positive for ANA, should be tested for specific antibodies indicative of the various systemic rheumatic disease.

Anti –DNA Antibodies 

Although several diseases are associated with anti ss DNA, the presence of anti ss DNA in higher titres is relatively specific for SLE. Low levels of these antibodies are sometimes seen in normal persons and individuals with Rheumatoid arthritis. In SLE their presence correlates with the presence of nephritis and disease activity.

• When there is s/s of Systemic Auto immune Disorder ( Low grade fever, Fatigue , weakness, Red Rash(lupus), Muscle pain , numbness and tingling in hands or feet, Arthritis like pain in one or more joints , Inflammation and damage to organs and tissues including Kidneys, lungs, heart and blood vessels)

• SLE 
• Scleroderma
• Sjogren’s syndrome 
• Raynauds disease 
• Rheumatoid Arthritis
• Auto immune hepatitis
• Polymyositis