Question:
Anti-Sm is indeed Anti-Smith antibodies — referring to antibodies made against an intracellular protein. A suggestion — you should be seeing a good rheumatologist for diagnostic work rather than a neurologist. Your MD may very well be out of his league. >** Note: My MD (neuro) says "ANTI-SM" means "anti-smooth muscle", whereas >my searches on the net suggest this means "anti-smith" antibody. Which of >us is correct here? **
– ************************************ Michelle Garrison University of Washington
Response:
As an ex-tech doing such tests, I can say with nearly 100% conviction that the SM referred to in RNP & SM antibodies (Negative 41) would be Smith antibodies and should have ben written as "Sm". The Anti-SM referred to on it’s own (Positive 492) would be Smooth Muscle antibodies and is correctly written as "SM". At least, this is how my lab would have produced such results! Regret, not qualifid (or able!) to help in any other way. Regards Andrew – Hide quoted text — Show quoted text -> Panel Lupus Screen > ANA: Neg > Anti-DNA/DS: Negative 41 > RNP & SM antibodies: Negative 0 > ANTI-SM: Positive 492 VH > ANTI-SSA: Negative 0 > ANTI-SSB: Negative 0
Response:
In this context, I agree with Michelle, anti-Sm means anti-Smith, which would be part of a Lupus panel, along with anti-Sm/RNP, a separate test. The result is puzzling, since Sm antibodies are considered highly specific for lupus, in which case the ANA should have been positive as well. Also, it is virtually impossible to have anti-Sm antibodies without also being positive for Sm/RNP. So we have a very high Sm, flat negative Sm/RNP and a anti-dsDNA result which would be considered borderline (anti-dsDNA is also specific for lupus). I agree, consult a rheumatologist. – Hide quoted text — Show quoted text -> Bloodwork: > ========== > Panel Lupus Screen > ANA: Neg > Anti-DNA/DS: Negative 41 > RNP & SM antibodies: Negative 0 > ANTI-SM: Positive 492 VH > ANTI-SSA: Negative 0 > ANTI-SSB: Negative 0 > Complement C-3: 114 > Complement C-4: 40 > RA Factor: <20 > ** Note: My MD (neuro) says "ANTI-SM" means "anti-smooth muscle", whereas > my searches on the net suggest this means "anti-smith" antibody. Which of > us is correct here? **
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