Does stress cause ana weak positive blood test cause i got a weak positive does it mean i will get an autoamune illness later in life ?

Weak positive?: What blood test are you referring to? Sometimes doctors test for ANA (antinuclear antibody), and results can be confusing. The "weak positive" can be a false one, and may not indicate any autoimmune illness at all. Positive ANA is fairly common, even in healthy people -- 20% of women, and 7% of men! http://tinyurl.Com/mp64o5m if you have no other symptoms, i would not be concerned about it.

No and no: Stress does not cause a weakly positive ANA and that test alone does not increase the risk of developing autoimmune diseases in the future. Consider a weakly positive test the same as a negative test.